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davidmij
07-19-2014, 07:15 PM
I was testing my car out and missed a powershift from 2nd to 3rd. It revved to about 6K, but that shouldn't be a problem in and of itself. Anyway, I drove a couple of more miles back to town and when I came to a stop I noticed the motor was missing a little. I don't know if this is related to the rev, but thought I should mention it.

If I drive it at low RPMs it misses, but if I get it up to wide open throttle it runs fine.

I pulled a plug (#8) and noticed it was blackish. I decided to go through all the plugs one at a time to see if a fouled plug was the problem, it wasn't. I noticed that plugs from cylinders 4, 8, and 1 were blackish, I think the others were OK color wise. Another thing I notice is that the primary side of my Edelbrock 1407 is a little black too. Is this an indication that I have my idle set too rich?

Next I tried all the plug wires, but no help.

I decided to listen to each side of my exhaust, they are independent sides with cheap little 18 inch glass packs. I couldn't really tell anything sound wise, but when I put my hand over the exhaust I noticed the drivers side felt noticeably cooler than the passenger side. I have no idea if this means anything, it's just a rookies observation.

Any advice on what to look at next? Or even a troubleshooting flow chart type process?

regards, Dave J

simplyconnected
07-19-2014, 09:30 PM
Dave, armchair troubleshooting isn't going to be of much help on this one. Pull your valve covers off and look.

We can play, 'you could have' all day but the real answer is a mechanical failure. You are right, 6,000 rpm's is not a biggie IF you were developing HP. Sounds to me like you were not.

Idle speed tells us a lot more than high rpms. A black spark plug may point to the cylinder that is at fault, but keep troubleshooting. There is more to this story. Take videos and let us know what you see when running the engine with the valve covers off.

BTW, now you know why I run with an automatic trans. It has never missed a shift and it never stops developing HP through all the gears. - Dave

davidmij
07-19-2014, 11:07 PM
Thanks Dave, so if I pull the valve covers I can run the motor and video at the same time? I would have thought that it might make a mess? My lack of knowledge coming to the front once again.
I did take pix of the plugs, here they are.

Is the slight blackish primary's an indication of anything? I was thinking carburetion because of the miss at low RPM's and then it's OK when I get to "all in".

I missed the shift from 2nd to 3rd at about 5200, it shot up to 6000. It pulls really well all the way from 2500 - 5500 rpm.

simplyconnected
07-20-2014, 12:31 AM
I was testing my car out and missed a powershift from 2nd to 3rd. It revved to about 6K... ...when I came to a stop I noticed the motor was missing a little...Things normally break at high rpms but rarely at low rpms.

You can take the valve cover off the side you suspect is bad and run the engine. The idea of taking a video is so you can watch it many times because you will not notice everything the first time.

Pay attention to the rocker arms:
Are any broken? (Yes, I have seen a broken rocker arm.)
Do all of them go all the way up and down, or is there one that is 'lazy'? The pushrod side should travel ~1/2" but the valve side should travel ~3/4"
How do the lifters sound?
Do you see oil coming out of each one?
Are all the pushrods straight when you spin them?

I do this test with the engine off and the rocker shaft loose or removed: Next, take a rubber mallet and hit the valve stems. The intakes should all sound the same and the exhausts should all sound the same. If one doesn't return or if it is hard, (you can tell the difference) then the valve and guide need work. This can happen if you floated your valves, one hung open and the piston closed it (causing a bent valve stem and/or broken guide).

Another check is to blow air into the cylinder: Gut an old spark plug and weld a male air hose fitting in the base. Screw it into the spark plug hole and rotate the engine so both valves are closed. Turn on the air and listen. If hissing sounds come from the carb you have an intake valve problem. If sounds come from the exhaust, the exhaust valve is bad. If sounds come from the bottom of the engine (through those oil return holes in the heads), your rings are blowing by.

A simple compression check will tell you which cylinder is bad but it won't tell you 'why'. - Dave

davidmij
07-20-2014, 08:50 AM
Thx Dave.
I'll try these things when I get some time. I'm tied up today on other "must do" chores. I may take a day off work and do it.

I'll also resize my pictures of the plugs that didn't post and try to post them.
Only one of the plugs was actually a little shiny so I'll start on that bank.

thx again, Dave J

Joe Johnston
07-20-2014, 09:40 AM
Are all the pushrods straight when you spin them?

This is the first thing I would check :o
(Been there and done that over revving thing more than once!!)

davidmij
08-03-2014, 12:36 AM
Finally got a chance to do some troubleshooting today. I ran the engine and pulled the plug wires one at a time on the drivers side. When I removed 5,6,or 7 the motor got worse. When I pulled number it stayed the same, thus it appears that number 8 is the problem.
I tried a new plug (again) and it didn't help. I checked the spark coming out of the plug cap by holding it close to the head and it arched, thus showing that I have spark.

Next I pulled the valve cover and checked it out, everything looks good to me. I ran the engine and oil is flowing as I think it should. The number 8 very end valve has a very very slight ticking sound. I could hear it faintly with a stethoscope.

One at a time I made sure the valves were seated, then tapped them with a rubber mallet. Each one sounds the same and snaps right back.

I posted 2 videos at this link. (The first video is an old one with the old motor) In video 3 it was running with the choke on at first - at 50 seconds in I turned off the choke and it was idling. I don't see anything, but I'm not very good with the camera. I guess next I'll need to find some one with a welder and try to rig up the spark plug test.
Any thoughts at this point?

thx, Dave J

https://plus.google.com/photos/101492851059660555641/albums/5847780077150861489?banner=pwa&authkey=CP-5_a-_v-Pf7gE

simplyconnected
08-03-2014, 04:06 AM
...I posted 2 videos at this link...What you have is good, but I need to see more.

Pull back with your camera so I can see your distributor and the wires. I want to see 1-5-4-2-6-3-7-8 (both banks).

GO S-L-O-W with the camera AND your engine speed. If you need to move around, do it slow and don't get too close. If you stop, count to four before moving the camera again. I can tell more from a little farther back than I can looking at two valve springs. I see your pushrods rotating but you went too fast to see the middle ones. High rpm's make the video a blur.

The engine doesn't sound as healthy as it should. I definitely hear a miss in your exhaust but I cannot tell which side it is coming from. You narrowed it down to #8. That may be true but you may have other issues as well.

Get a propane torch and turn it on but don't light it. Wave the nozzle around #8 intake manifold/head separation. If there is a leak, your rpms will increase. BTW, if compression is good on #8, I'm not convinced your spark is right or your vacuum is not leaking. A simple vacuum leak will make your engine run bad because the air/fuel ratio will be different at each cylinder. The propane torch will find a vacuum leak very fast.

So, start a good distance above the distributor and pan slowly down the wires to each bank. Keep your rpms low and let's see all the valves from the front to the back of each bank.

Cell phones are ok for slow video. Camcorders run at 30 frames per second (FPS), much faster than cell phones (15-24 FPS). Again, move slowly to get the best video. - Dave

davidmij
08-03-2014, 09:20 AM
Will do Dave, thanks.
I forgot about vacuum leaks. I have noticed a couple of times while driving it that the power brakes feel off every once in a while. I don't have the back up air canister in the car so low vacuum could be a real possibility.

I'll try to get to it soon. Right now it's early here and I don't want to annoy the neighbors with a loud car at 7am.

thx, Dave J

davidmij
08-03-2014, 01:12 PM
I don't know if these are much better Dave, I think some people are just better with video than others.
It's weird, but it seems like it's running somewhat better now. I had pulled the brake booster line for pictures and forgot to plug it back in when I stated the car. When I noticed it, I plugged it back in.
Back when it first started missing I had to turn up the idle about 2/3's of a turn to keep it running around 650 rpms at idle. Now this morning, after unplugging and plugging back in the brake booster line, it idles at 900 rpm. So I turned the idle back down to about 680 rpm for this video of both banks. There is a definite clicking from the passengers side, but I can't tell where or which lifter it's coming from. I watched all 16 lifters and they are turning nice and true.
https://plus.google.com/photos/101492851059660555641/albums/5847780077150861489?banner=pwa&sort=1&authkey=CP-5_a-_v-Pf7gE

I'm using my camera that has built in HD video. The trouble is Panasonic uses their own weird video format. So I have to convert it to MPEG - when it converts it it loses quality.

thx, DAve J

simplyconnected
08-03-2014, 03:48 PM
...I don't have the back up air canister in the car so low vacuum could be a real possibility...You have plenty of canister. You should be able to shut your engine off, wait a few seconds, and still have enough power brakes for at least two pedal pumps. If you don't, then you have a vacuum leak or your check valve/seal is faulty.

I normally pull the vacuum hose off the other end of the check valve and I put a bolt in the hose to block it off. Then, I do my engine tests.

You are running a street cam which makes it harder to get a smooth idle because of duration. Do you have a heat riser valve? (That may be your clicking noise.) Is it clearly open when your engine is at idle speeds? Did you block off your exhaust crossover at the intake manifold? If you have a heat riser valve, make sure it opens all the way when you rev the motor.

The valves look good, I didn't see any bent pushrods. It's time to take the car for a spin and let us hear what this engine sounds like. (You said the last vid was with the old engine. I don't want to confuse the two.)

If you can, leave the power brake plugged during your test run. Just be careful to give yourself plenty of room to stop. You will know if the problem is a vacuum fault or not. After running a few starts, put the vacuum hose back in the booster (to re-establish power brakes). Do a few more starts and notice the difference. There shouldn't be any difference at all. - Dave

davidmij
08-03-2014, 09:13 PM
What I meant was, I removed the canister completely back when I installed the power brake set up. I don't have one. If you look at the video you can see that it just has the one line from the carb to the brake booster.

Anyway, with the motor off, each time I pull the hose off the brake booster there is a swoosh sound as it sucks in air. I pulled the hose anyways and plugged it, but it doesn't make any difference in the idling or when I take it for a drive. I think the brake pedal felt a little weird because the engine is missing and messing up the vacuum.

It has an Edelbrock intake and FPA headers so it doesn't have a cross over or a heat riser.

I also have used the propane torch all around the intake and the carburetor base, no change in idle. I pulled the number 8 plug wire again and it doesn't change the idle at all. Then I pulled the number 7 and the engine almost dies. It just has to be something with that number 8.
The only thing I haven't replaced is the dizzy cap, but it was new about a year ago and seems fine. When I pull the number 8 wire off the plug and hold it to the block it arks and I can hear it firing away. It's not very rhythmic though, I wonder if the dizzy cap could be intermittent and missing???

I still hear a slight ticking or tapping around the end of the number 8 cylinder. It almost sounds like it could be coming from the firewall. What's weird is that I put on my stethoscope and touch it to everything and I can't find the sound. Maybe it's electronic.

I have good vacuum when I pull the PCV valve from the passenger side valve cover.

I think it may be time to just take it to my corner mechanic Herman and pay him to hook it up to his machine. This is getting way difficult to troubleshoot via blog.

It's time to take a shower and get ready for the work week.
I really appreciate all the effort and help Dave!

Have a good one, Dave J

simplyconnected
08-03-2014, 09:21 PM
...I pulled the number 7 and the engine almost dies. It just has to be something with that number 8...Swap wires (on both ends) and see if your troubles move to a different cylinder with the wires.

Pull the distributor cap off and make sure your coil (points) wire isn't touching ground as the rotor turns. - Dave

davidmij
08-03-2014, 10:16 PM
Yeah, I changed the plug wires using two older original wires at a time when I first started checking the plugs and wires.
Today I tried switching 7 and 8 completely. I also made sure 7 and 8 weren't touching or crossing, I've heard that can cause an issue.

No points, I have a Pertronix set up. I pulled the dizzy cap and checked everything out. Regapped it too.

I also checked the timing, etc.

The thing that gets me is that it runs good above 3000(ish) rpms and really pulls all the way up to higher rpms.

I'm worried it's something with that cylinder and valves.

You know, it's not so much a miss, what I mean is that it doesn't cut out. It's more of a fluttering kind of thing/miss.

Dave

DKheld
08-04-2014, 09:15 AM
David J - hate to hear your having engine problems - was hoping to see that thing smokin' some tires down the track.

Can't remember - you still using hydraulic lifters? I'm thnking not but if so maybe it's just a failing lifter or one with something stuck in it? I definately hear the tick - sounds like my 352 after it sat untouched for 4-5 years. I had to run marvel mystery oil in it to free up the lifters. (actually both of my engines - the original that sat for 4-5 years and the new engine that sat for the same amount of time after being rebuilt but not run - the lifters were sticking when I first ran it too). If you are using hydraulic lifters they are probably new so marvel won't work but could be a new part failure?

On the other hand......

Dave D. - wonder if an exhaust or intake seat has come loose and only shows up at an idle because it has "time" to drop out of the head?
How do you check for that - a leak down test?


Eric

davidmij
08-04-2014, 10:13 AM
Hey Eric, yes, it has hydraulic lifters. When I watch the rockers it looks like the push rod and valve stems are staying seated just fine. And, if it wasn't visible to the naked eye, I would think that I could pick up the tick with the stethoscope, but I don't.

As for the valve seat dropping, would that be possible if I don't have hardened seats? The builder said there wasn't enough room for the seats with the cobra jet sized intake valves. He also said that a good seasoned head will be fine with a lead additive which I do use religiously.

Dave J

jopizz
08-04-2014, 02:21 PM
Maybe it's just an optical illusion but it looks to me like the #8 rocker arm (on the end) has some play in it. You can trouble shoot whether it's a valve tap you're hearing by putting a thin feeler gauge between the rocker arms and valves and seeing if it goes away.

John

davidmij
08-04-2014, 05:37 PM
Hey, that's a great (and easy) idea John. Thanks, I'll try it tonight if we get a break in the rain.

I'm also thinking of spending a few bucks and replacing the dizzy cap. It's the last electrical thing in the loop on that cylinder.

Dave J

davidmij
08-06-2014, 08:58 PM
Wow, this is very strange to me, but as you know I have very little car experience.
I bought a new dizzy cap just to eliminate the last electrical thing going to the #8 cylinder. It made no difference in the miss.
OK, remember that I said, "If I pull the #8 plug wire it idles the same, but if I pull the others it almost dies". Well, that's still happening. However, I tried the same thing on the passengers side and when I pull the #1 plug wire it idles the same. So, I can pull #1 and #8 and it idles no differently. That means I'm running on two cylinders. If I pull any other wire it almost dies. But then again, that should be expected because it's running on only five cylinders.

Is this starting to look like the cam at the end of the block by the #1 and # 8 cylinders is messed up?

Just thought I would ask, I'm taking it my corner mechanic tomorrow.

I have video with audio if you want to see what I mean
Dave J

davidmij
08-08-2014, 03:04 PM
Just got back from my mechanic. First thing he thought was a vacuum leak so he sprayed around the intake with propane but there was no change. Opened the rocker covers, all looked good to him. Had his son do a quick compression check on number 8 and number 1, zero compression!
He noted that the exhaust smoke looked fine, so he believe's it's most likely the intake manifold gasket.

I'm going to pull the intake today and see what gives. He suggested having the intake skimmed over (machined). It's an Edelbrock aluminum performer RPM.

I'll let you know what I find after I get the intake off.

DAve J

simplyconnected
08-08-2014, 03:44 PM
...Another check is to blow air into the cylinder: Gut an old spark plug and weld a male air hose fitting in the base. Screw it into the spark plug hole and rotate the engine so both valves are closed. Turn on the air and listen. If hissing sounds come from the carb you have an intake valve problem. If sounds come from the exhaust, the exhaust valve is bad. If sounds come from the bottom of the engine (through those oil return holes in the heads), your rings are blowing by.

A simple compression check will tell you which cylinder is bad but it won't tell you 'why'. - Dave <--this was from post #4.


The engine doesn't sound as healthy as it should. I definitely hear a miss in your exhaust but I cannot tell which side it is coming from. You narrowed it down to #8. That may be true but you may have other issues as well.

Get a propane torch and turn it on but don't light it. Wave the nozzle around #8 intake manifold/head separation. If there is a leak, your rpms will increase...

I seriously doubt your intake manifold gasket would cause zero compression. Something more serious is going on. I don't know how old your rebuild is. Your valves may be burned or they may be receded (causing them to never close or seal).

This is why it's so important, when doing an overhaul, NEVER scrimp or cut corners on the heart of your engine (your heads).

An aluminum intake manifold is wonderful but I would much prefer they start by spending the money on aluminum heads, first. All the correct parts are already inside Edelbrock performer RPM aluminum heads. in other words, they are built for today's fuels. - Dave

scumdog
08-08-2014, 05:41 PM
Just got back from my mechanic. First thing he thought was a vacuum leak so he sprayed around the intake with propane but there was no change. Opened the rocker covers, all looked good to him. Had his son do a quick compression check on number 8 and number 1, zero compression!
He noted that the exhaust smoke looked fine, so he believe's it's most likely the intake manifold gasket.

I'm going to pull the intake today and see what gives. He suggested having the intake skimmed over (machined). It's an Edelbrock aluminum performer RPM.

I'll let you know what I find after I get the intake off.

DAve J

Ummm...even with NO intake manifold in place there should be good compression if all is well with the rest of the valves/cam/rings etc.

Is your cam still good? - no 'flat' lobes etc?

Are the valves for the weak cylinders moving as much as the strong cylinders valves?

davidmij
08-08-2014, 07:22 PM
Ah crud, I just realized you're right Tom. I was thinking to myself, "how would that gasket blow anyways? There's no real pressure on it."
The valves and lifters all looked like they are traveling the correct distance. I'll look at the video again.... Yup, they look good. If it were the cam, or a poorly seated valve, it wouldn't do that would it?

Dave, I think I said it before, but I don't have a welder to make up the spark plug air pressure test tool you described. I guess I could try my cheap little pancake compressor with a rubber plug seated in the spark plug hole. I could have a buddy hold it there while I listen. The hardware store should have what I need. I borrowed a compression tester from Autozone years ago and had no luck getting readings off of it. These are both reasons why I went to my mechanic. He checked it out in about 20 minutes and didn't charge me anything. I also said that I tried the propane torch around the intake. That one I could do. It didn't show me anything though.

So, do you think I'm back to bad rings? That was the first thing my mechanic thought. But wouldn't that be evident by the exhaust? I can't see any other way I could be loosing compression.

What about a blown head gasket on the part of the head inside the motor? But I would think that would make a pretty nasty sound out the exhaust wouldn't it?

I understand what you're saying Dave about skimping on the build, (by the way, the build is only about 1000 miles on it).
Other than the having the heads reworked with CJ size valves this engine is far from a skimpy build. It has all new ARP fasteners, new 410 pistons, Lunati cam, 428 oil pump, lifters, guide liners, comp springs, stainless steel valves, moly rings, the rockers were refaced and rebuilt, squared block, thin wall brass guides, valve shims, I don't remember what else.

Doing the heads this way cost about $900. If I went with modern Edelbrocks I'd be in for almost triple that. I planned on buy Edelbrock heads in a about 5 or 6 years. I just don't make all that much money.

Before I tear down the top of the motor I'll try rigging up something to do the pressure air test in the spark plug holes.

I'm still enjoying this car, but I'm learning most everything the hard way.

Thx a ton again for all the help and comments gents. I hope I'm not frustrating you too bad.

regards, Dave J

fcar
08-08-2014, 07:27 PM
Hang in there and Good Luck!

simplyconnected
08-08-2014, 07:30 PM
...Is your cam still good? - no 'flat' lobes etc?
Are the valves for the weak cylinders moving as much as the strong cylinders valves?Tom, you can see the valves deflect in his videos.

What you cannot see is if the valves have receded into the head. This is a big problem with unleaded gasohol; a product our classic cars were not designed for. Yes, they work for awhile, then it creeps up on you. When valves recede, they never close. The stem keeps getting higher and higher. Soon, the lifter is pushed too far down and the valve remains open at the cam base circle.

Look at the first and last pictures on my site:
http://squarebirds.org/images_FE-valves/
These heads came off a '73 F-100 pickup truck, not a race car. Notice the small exhaust valves on the ends.

Hmmm... 'on the ends'. Doesn't that sound familiar? Jones said #8 and #1. Now look at the pictures in the site again. The end valves are receded farther than the middle valves. See a pattern here?

http://squarebirds.org/images_FE-valves/DSCN0279.jpg
I gave these heads to my neighborhood scrap man because I want no part of them.

You can spend a boat load of money machining, buying stainless valves, Viton seals, bronze guides, and hard seats. What you end up with is a cast iron head that will still not transfer heat well but it will burn unleaded gas. For a little more, buy the Edelbrocks off the shelf and bolt them on. Even used aluminum heads are worth a grand. Rebuilt used cast iron? US$200 max. - Dave

simplyconnected
08-08-2014, 08:08 PM
Dave, I'm enjoying your posts. I hate seeing anyone put good money after bad. It's counter-productive and wastes money.

This is where a GOOD, experienced engine machine shop (and engine builder) should sit you down and warn you about the consequences when corners are cut. I want to save money just like everyone else, but look what's happening. If what I predict comes to pass, you will at least pull both heads, machine exhaust valve seats, pound in some new ones, and do a complete valve job. It's all additional machining costs.

Summit wants $809.00/each (http://www.summitracing.com/parts/edl-60069) (shipped) for Performer RPM heads (assembled). These include 2.09" intake valves. That's $1,618 per pair, not $2,700.

It's always a money-saver if you can buy production parts instead of having an individual perform custom machining. If this was a 'pure stock' situation, the rules change. Yours is centered on high performance, and for longevity you must demand the good stuff.

BTW, in my last post, the valves look perfect. - Dave

davidmij
08-08-2014, 08:42 PM
Man, once again it sure looks like your correct Dave.

I've heard it a bunch of times that the old seasoned steel in these older heads will be OK if you use a lead additive, which I do religiously. What I failed to factor in is the high performance build - that's where everything you're saying makes complete sense.

I'm going to rig up the air compressor test somehow, and test it out tomorrow. That way I'll know what the heck's going on.

Nick, thanks for the words of encouragement.

I'll let you know what I find.

Dave J

davidmij
08-09-2014, 05:52 PM
Just realized that I have been saying the number 1 and 8 cylinders. It's actually the number 4 and 8. But anyways.

I looked up how to hollow out a spark plug and did just that. Used my rubber tip on the air compressor and held it tightly in the plug tool. Sure enough, the exhaust valves are not work on either cylinder.

The only good part is that I can do the work myself. When I first pulled the donor motor out of the 67 LTD I pulled the heads to replace a blown head gasket. I used my manual and some other resources to do all the work and it came out pretty good. Heck, with all the room I have in this engine bay I won't even have to pull the motor. The FPA headers can come off with the heads and go back on with the new ones.

I guess the hard part is going to be assembling the rockers and making sure all the shimming and rod lengths are where they should be for the new Edelbrock heads. I'll have to read up on how to do that.

Thx again everyone!

Dave J

DKheld
08-09-2014, 06:08 PM
......... but as you know I have very little car experience.........Dave J

You are doing a lot more than many folks can these days. Sounds like you won't be able to use that line much any more - you're getting some good experience.

Sorry to hear you have to take the engine apart. Hope this will be the last time then enjoy it for a while. Drop us a pic and let us know how it looks when you get it apart - I'm just curious.

Eric

davidmij
08-09-2014, 07:24 PM
I'll definitely do that Eric. You guys can tell a lot more than me with pictures.

thx, dave

simplyconnected
08-09-2014, 08:33 PM
Jonesy, my hat goes off to you. I admire that you're doing your own work. even if it is to save money. That's exactly how I got started wrenching.

I am sorry that you're going through this again. There are some advantages, though. Novice-Mechanic days are behind you, now. It's all uphill from here.

I take it that you will go with Edelbrock heads? If so, they are a direct bolt-on replacement. Pushrod lengths remain the same, rocker shafts remain the same... it's all good. The only 'custom' calculations I had was due to the roller cam I installed. Roller lifters are at least one inch taller, making the pushrods one inch shorter. You won't have that situation.

You said your machine shop 'squared' your block. They probably shaved your heads as well, to make them flat. Did you change pushrod lengths? Probably not. Hydraulic lifters are awful forgiving, even though your machining 'stack' pushed them down about .030". With new Edelbrock heads, you're going to get some of that back (unless you mill the new heads).

Follow my build pictures and suggestions. They will save you time and money. By all means, take hundreds of pictures as you are tearing down and building your engine. They are wonderful references. If you don't use them maybe someone else will. That's the attitude I took when I documented the Penelope build. (Remember, I don't own a Thunderbird except for the '58 convertible model that Eric Taylor sent me.)

I'm glad you are on this forum. Given the chance, Squarebirds.org offers tons of experience and knowledge that most garage mechanics are missing. Use this forum to 'talk problems out'. We can only suggest the direction you should go. Ultimately, you will do what you think is best. - Dave

fcar
08-09-2014, 09:27 PM
Congratulations, Dave. Your perseverance is/has paid off, and I know that I've learned from this thread.

davidmij
08-09-2014, 11:58 PM
Awesome, I'm glad I don't have to worry about tolerances etc. with the hardware.
Yes, the decks and heads were milled, shaved, (whatever the terminology is). I think I still have my old card board boxes that I used to organize all the pushrods and fasteners.

I have over 500 photographs, many from the first time I pulled it all apart, and just like you advised a year and half ago, those WILL come in handy for doing it again.

In about 3 years I'll be ready to retire, and when I do I'll have tons of time to play with this hobby. The plan has always been to do as much as I can myself. It's not much of a hobby if you pay some else to do the work. I've actually got a pretty good budget right now. After I get it all apart and verify what work has to be done, (and whatever else might need fixing) I'll order the hardware.

I just bought a 2 ton engine lift on Friday. I found it on Craigslist for $120, - it's almost new. I just may be putting it to use sooner than I thought!

Funny, some of my buddies call me "Jonsey". Some of them call me other things too. I'll leave it at that.

simplyconnected
08-10-2014, 02:37 AM
...I have over 500 photographs, many from the first time I pulled it all apart, and just like you advised a year and half ago, those WILL come in handy for doing it again. As a tradesman, I always worked as if I might need to redo this, like changing motors, etc. Many times it was someone else but we could always tell who did the work. Some electricians wired motors with wire nuts, others with butt splices. I used crimped lugs with screws and nuts. So if the same motor went bad on my shift, I appreciated the extra effort that was already in place.

The point is, you never know who will work 'behind' you on any job. It might just be yourself. Having those pictures are a tremendous help because it's impossible to remember all the details. When you put those pictures in your computer, do not downsize them. Leave them large so you can zoom-in on details. If you want to post some, then downsize and have two copies, but don't alter the originals.

...I just bought a 2 ton engine lift on Friday. I found it on Craigslist for $120...

Funny, some of my buddies call me "Jonsey"...That's a decent price for the cherry picker. You can always sell it for the same money.
I took the liberty of calling you 'Jonesy' in hopes that I'm one of your buddies, too. - Dave

davidmij
08-14-2014, 08:20 PM
Got the heads off one side and see the problem. Not sure if these pictures will show it very well, but the exhaust valve on #8 is tilted slightly. I'm guessing #4 will show the same.

I also thought I'd show a cylinder and two other valves. The cylinder wall shows a slight scratching, however if I touch it I can't feel it there.

Anyway, I'm going to order some Edelbrock's once I get advice from Barry Rabotnick, owner of Survival Motorsports. He's on the FEpower forum I visit for advice sometimes. I'll give him all my engine and cam specs and I should end up with what'll work best on this motor.

stay tuned for more from Dave Jones and his Bird with a broken wing.

jopizz
08-14-2014, 08:35 PM
There are a number of reasons why the valve is not closing. It could be slightly bent; there could be a buildup of carbon on the seat or the seat could be damaged. Without removing it it's hard to tell what is going on. As far as the cylinders go you should see crisscross scratches. This is part of the honing process. This helps retain oil and reduce cylinder and ring wear.

John

simplyconnected
08-15-2014, 05:17 AM
To me, that valve looks like the piston closed it. The problem with that is, the valve stem is not in line with the piston bore, so the valve 'cocks' to the side, sticks in the guide and the valve bends.

This usually shows up when you 'pop' it with a rubber mallet, smacking the valves down. Bent valves tend to stick and an open valve sounds quite different from all the rest that close properly.

It's not a receded valve but one that never closes, none the less.

So, what causes a valve to bend? Floating your valves from rev'ing to very high rpms and/or no oil going down the guides.

The valve train is massive and hard to move fast. Racing engines use very strong valve springs and shims to overcome the kinetic energy to return a valve. Overhead valve trains cut down on kinetic energy by eliminating the pushrod and keeping the lash-adjuster (lifter in your case) from moving. With fewer things to return, that's why their rpms are so much higher.

Starved oil can bind a valve stem. That's why it's so important to keep your rocker shafts clear, for oil to freely flow in each rocker arm. Each one only needs a little oil but it has to be there. - Dave

davidmij
08-15-2014, 09:48 AM
Dave and John, your comments had me taking a second look this morning. In these pictures of the top of the piston in question you can see that the eyebrow seems to have a ding in it on the exhaust valve side. Sure looks like possible valve float. The first picture shows #8, the second picture shows a good cylinder without a ding in it.
The cross hatch cylinder polish lines that you talk about John are there. They look good. I just noticed that there are some veeeery slight in line marks showing up in the number 7 cylinder. It's not detectible by palpating the cylinder though. I don't think it's anything to worry about.

I wish I had one of those higher end tachometers so I could see what the actual rev was when I missed a gear power shifting. I saw it at 6000rpm, but who knows how much above that it actually went.

Anyway, I think I'll try to sell these heads and just go with the Edelbrocks. Years from now I plan to go to a 445 stroker and will eventually want them.

Later today I'll get the other side off and post pictures of that side. It's be interesting to see it the #4 did the same thing.

I don't understand the pattern, or layout of the oiling paths in the heads, so maybe you guys can tell me; does the firewall end of the heads not get as much oil as the rest of the head and valves?

thx, Dave J

simplyconnected
08-15-2014, 10:17 AM
...I don't understand the pattern, or layout of the oiling paths...On the driver's side (LH), look down the rocker shaft bolt hole, second from the front. Both heads are identical so the RH head would be second from the rear.

Right next to the bolt hole is the oil feed hole. I covered this with an oil restrictor in my Penelope build. That bolt in the rocker assembly tower should look skinnier than the other three, to give oil more room to travel up the stand and into the rocker shaft center. Once inside the shaft, oil should come out every rocker arm in two small holes, each. Of course, when you built this engine, you would have cleared out those holes with a small drill bit when all the rocker arms were off their shafts. They tend to varnish closed, trapping dirt that acts more like cement from so many years of dirt settling and cooling.

I'm concerned about your piston-to-valve clearance. What is it? - Dave

davidmij
08-15-2014, 01:28 PM
I remember the holes now Dave. When I took the motor out of the donor car I took the rockers completely apart and sprayed cleaner through all those holes per an article or instruction that I had found.
The heads and rockers were completely rebuilt by the guy that did my motor. That included valve job, surfacing the pair, thin wall brass guides, spring height sets so they would all match, regrinding etc.

I too am VERY concerned about the clearance Dave. How can I check it? I've been told that the Edel heads have a slightly smaller chamber size than stock. I'll make sure and talk this over with the guys from Survival motorsports to see what they think or recommend. I'm sure they'll want to know the clearance too.

Dave J

simplyconnected
08-15-2014, 04:14 PM
...I too am VERY concerned about the clearance Dave. How can I check it?... Pull the valve springs off of a pair of valves from any good cylinder. Hold the valves up with anything (tape is good) from on top. Replace the head with the head gasket and torque it down.

Slowly hand crank it until you can feel the exhaust valve touch the piston. At the highest point, with the least amount of 'lash' or clearance, measure the valve stroke. It won't be much so measure it carefully.

Now let's check with your cam. Put your rocker shaft and pushrods back on in the cylinder you are checking. Again, with no valve springs, hand crank and feel the highest point at which your valves touch the piston. Do NOT let the valve drop down the cylinder or you will start all over. Some guys put a very light spring on the valve to check it. When you get to the closest point where it has the least lash, you can use feeler gauges between the valve and rocker arm. Do each valve separately.

None of these tests cost money but they should have been done at the time your engine was built. The problem with that is, most mechanics won't spend the time because they'd need to charge you more money. Now you know why I do my own.

BTW, check the bent valve's guide. It may be broken at the bottom. - Dave

davidmij
08-15-2014, 07:22 PM
Thx Dave, I think I can follow that. I wasn't able to work on it today. Family stuff with my dad's health, and getting a resume together this weekend. It'll probably have to wait once again until next weekend.
The builder told me that they shimmed all the valves to be at the same height, or stroke, if you will.
I just did the rubber mallet test on the passenger side, I haven't taken that head off yet. I can definitely tell the #4 and maybe even the #3 exhaust valves are hurt as well. I kind of found that out already via the hollow spark plug and air compressor test anyway.

Dave J