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topdeadcenter
04-27-2014, 09:55 AM
Hello everyone,

So on the 330 mile drive back from picking up my "new to me" 59 HT from Duluth, MN yesterday, the car was pushing about a quart of oil out of the breather every 75 miles or so.

Any ideas about why? and any fixes?

Couple things to note:
1. Engine (352) was rebuilt in 2007 and has less than 7000 miles on the rebuild. (I have the reciept).
2. I was driving the car at 68-72 mph at this time. Yes I know that they were not built to drive at that sustained speed, but I also have owned 6 pre-70 cars in my young life and have never had any problems like this on any of the other ones driving at that speed.
3. The breather appears to be a cheap chrome "hot rod" part. So I am wondering if the original had a baffle before the filter to keep the oil in the intake?

Any and all thoughts and opinions welcome. Except the ones from the old guys that are just going to tell me not to drive that fast. ;) Because that is just not an option :D

Mike

jopizz
04-27-2014, 10:07 AM
Assuming that the rebuilt motor was broken in correctly and didn't sustain any initial damage you shouldn't be losing any oil regardless of how fast you are driving. Do you still have the original intake setup with the breather tube out the back and the oil fill cap or has it been changed. It sounds like you have an oil cap in the valve cover by your post. If the manifold was changed you should have some sort of pcv setup.

John

topdeadcenter
04-27-2014, 10:16 AM
The set up is original. There is a road draft tube out the back of the intake and the breather is on the oil fill tube. There is no PCV setup.

I have to assume the car was broken in correctly, but I don't have anyway of knowing.

Was there a baffle on the original filler cap/breather on these cars?

jopizz
04-27-2014, 10:27 AM
The original oil cap has a mesh filter to filter air coming in but there should be no oil coming out the tube. It's possible that you have a blockage in the intake or the mesh screen in the road draft tube is blocked. Another possibility is that you have a blocked oil return in one of the heads. I would take the valve covers off and check them. There are returns at the front and back of the heads.

John

Larry
04-27-2014, 01:18 PM
Worst case scenario, a scored cylinder wall where you are getting a lot of crank case pressure. Some causes are broken rings due to pre ignition or broken rings during assembly, piston gaulding due to excessive heat or insufficient piston to wall clearance, wrist pin keeper or keepers did not get properly seated and came out allowing the wrist pin to contact the cylinder wall and scoring it. Hope it is none of the above.

Buckaroo
04-27-2014, 10:47 PM
Our Mustang was blowing oil out the breather and we found out the valve seals were dried out and some were even gone completely. Replacing them helped the oil blowing. You can replace them easily with the engine in the car.

topdeadcenter
04-28-2014, 08:56 AM
OK... so after a bunch of test runs and trying to determine just how much oil is being lost, over the course of the day the amount of oil coming out the breather went down dramatically. HOWEVER, the amount of oil lost is staying the same. Weird!

I don't see any blue smoke at start up or at idle, but there was a LOT of black soot coming out for the first few start ups and when I would "goose" the peddle.

Looks like I get to teach myself how to do a compression test today.

Larry
04-28-2014, 09:18 AM
OK...

Looks like I get to teach myself how to do a compression test today.

I think that would be a good place to start.

DKheld
04-28-2014, 11:28 AM
I make a 200 mile trip regularly in my Tbird. If I fall below 70 MPH I'm afraid I'll get run over. Sometimes I have to check and make sure it didn't slip into reverse :rolleyes:.

Still have my original 4100 carb on mine - it would make black spots every time I started it from being too rich. Rebuilt the carb and setting the float levels cleared that up.

I installed a rebuilt engine in my car - didn't know anything about the re-build - bought it from someone who was building a car and sold the car. I ran castor oil 10w 40 and added the ZDDP. Fortunately so far no oil consumption but I changed to PCV because the new engine did not have the road draft port on the intake. Bad part though is that I believe that the engine was not balanced properly - have a vibration around 80 MPH.

Hope you find a simple fix for yours......

Eric

http://media11.dropshots.com/photos/260234/20120129/105722.jpg

simplyconnected
04-28-2014, 03:14 PM
...2. I was driving the car at 68-72 mph at this time. Yes I know that they were not built to drive at that sustained speed,..These cars were built to sustain over 100 mph, all day long.

Compression checks are used to compare the difference in cylinders. This is important. Low compression is ok as long as all cylinders are low. If you have a few that are high, your idle will never be smooth.

Here's how you do it: Take a piece of paper and make two columns, one for each bank of the engine:

(Everything on a car is referenced from the driver's seat.)
FRONT
5.... 1....
6.... 2....
7.... 3....
8.... 4....

Write your compression findings on the dotted lines, then compare them to the firing order. Tell us what you get.

Usually, the end cylinders show lower compression because they get less fuel.
John's suggestion to remove your valve covers is always a good idea. While you are checking for dirt, also check for rocker arm oil flow and scoring on the shafts. - Dave

Astrowing
04-29-2014, 08:31 AM
1958 was the beginnings of the Eisenhower Interstate Highway System. That is the major reason for the new FE engine design and 300 hp Thunderbird Interceptor. Run 100 mph all day long.

topdeadcenter
04-29-2014, 08:37 AM
Couple things happened yesterday. 1. I found out that the compression tester that I got in a box of tools from my Dad must have grown legs and walked out of my garage. Hmmm? 2. I didn't mention it, but I replaced one quart of oil with Marvel Mystery Oil at some point on Saturday to see if I could loosen anything up. 3. The last warm-up and short run on Sunday didn't show any oil use/loss. And the 3 separate warm-up and trips yesterday didn't show any either. :D 4. While looking for a port to hook my vacuum gauge up to, I discovered a cracked cap on a vacuum line where the wipers used to connect (converted to electric). Once I replaced that cap, the idle smoothed right out. (it wasn't bad, but just a touch "lumpy").

Thanks to everyone for all your help! I am going to search the forum for speedometer correction now. I think the rebuilder must have put the wrong gear in when the tranny was rebuilt. 60 mph actual = 71 mph on the speedo and 70 mph actual = 82/83 on speedo. Actual speeds were confirmed with my GPS and the chase car that followed me back.

Astrowing
04-29-2014, 08:47 AM
I could only find one transmission driven gear when I was looking to use with my 3.10 axle, so my indicated speed is probably not correct and low also.

Larry
04-29-2014, 12:25 PM
2. I didn't mention it, but I replaced one quart of oil with Marvel Mystery Oil at some point on Saturday to see if I could loosen anything up. 3. The last warm-up and short run on Sunday didn't show any oil use/loss. And the 3 separate warm-up and trips yesterday didn't show any either. :D 4. While looking for a port to hook my vacuum gauge up to, I discovered a cracked cap on a vacuum line where the wipers used to connect (converted to electric). Once I replaced that cap, the idle smoothed right out. (it wasn't bad, but just a touch "lumpy").


Good news, maybe you just had a stuck ring or something. Hope it all stays good for you!

topdeadcenter
05-11-2014, 11:22 AM
I decided to run a compression test on the Tbird, since things still don't seem right. There is still some oil loss after even short trips. Some was due to a leaky valve cover gasket (fixed).

Here are my results:

#1
145 Dry
155 Wet
Spark plug: black, carbon fouled

#2
145 Dry
158 Wet
Spark plug: Normal

#3
125 Dry
135 Wet
Spark plug: black, carbon fouled

#4
148 Dry
154 Wet
Spark plug: partially carbon fouled

#5
130 Dry
127 Wet
Spark plug: Normal

#6
135 Dry
156 Wet
Spark plug: Normal

#7
120 Dry
130 Wet
Spark plug: Black carbon
#8
136 Dry
161 Wet
Spark plug: Gap bridged
from carbon

Any insight that any of you have into these numbers is appreciated.

I replaced the plugs and ended up replacing the wires too (cheap set on there lost a few ends when removing).

The car is obviously running rich, so today I am going to mess around with the carb to see if I can sort that out.

jopizz
05-11-2014, 11:55 AM
My feeling is that if you are running rich you are constantly scrubbing oil off of the cylinder walls which will affect your readings. I would fix that first and then redo the tests.

John

simplyconnected
05-11-2014, 02:40 PM
Glad you found your compression tester, Mike. Ok, so the rebuild is only 7,000 miles old. At this point the engine should be running beautifully and all the moving parts are properly seated.

Let's look at your compression results and compare them with the layout of the engine:
(5)..127__(1)..155
(6)..156__(2)..158
(7)..130__(3)..135
(8)..161__(4)..154

Of course, the left side shows the LH head and the right side shows the RH head.

We don't care too much about the real numbers as much as how they relate to each other. In other words, if the engine is expected to run smooth, the compressions must be in close relation to each other.

From the above findings, low and high readings are not at one end of the engine or the other, but are random.

Now, let's look at it in relationship to the firing order:
(1)..155
(5)..127
(4)..154
(2)..158
(6)..156
(3)..135
(7)..130
(8)..161
(1)..155
...

This is the real world. The first dip from #5, is 78% of the highest compression but it is in the middle of two 'average' compression readings. The second dip, #3 & 7, is more severe because two low readings are together, followed by high compression.

This engine would be difficult to tune for smooth idling and running. I assume the cylinders were bored and have new pistons and rings. That leaves valves to be suspect. The LH head is worse than the right but they are both not right. I would find out exactly what head work was done. (Were the exhaust seats changed? Were any valves receding into the head from gasohol use? etc...)

The fact that you are using oil may just be from the valve train in the heads. Were any valve guides replaced or reconditioned? If intake guides are sloppy, pistons will suck oil straight down the valve stem. Those 'umbrella' type seals are useless. They get hard, stick to the valve stem, and go up and down with the valve. (I use Viton seals that come with spring retainers.)

Heads are the heart of every engine. If a rebuilder cuts corners, it must not be in the heads. - Dave

davidmij
05-12-2014, 11:23 AM
Just an FYI, I use the Quaker State "Defy" oil. It come with the ZDDP (zinc) additive already in it. No problems at all.

Dave J

simplyconnected
05-12-2014, 01:58 PM
Zinc and phosphorus (ZDDP) is a 'last ditch' lubricant for hard mating surfaces like where your cam and lifters slide together under high pressure. If oil doesn't lubricate enough, ZDDP comes to the rescue. It also gets used up in the process.

Other engine parts don't need ZDDP. New engines use roller followers instead of lifters so they don't need ZDDP.

(ZDDP has very little to do with compression.)

jopizz
05-12-2014, 02:04 PM
Dave,

Do you find it unusual that the readings went up so much when he sprayed oil in the cylinders. I would think a rebuilt engine with less than 7000 miles would not show that much of a difference.

John

WoodlandHills
05-12-2014, 05:35 PM
Why hasnt a leak-down compression test been done? That will tell you where the leaks are coming from: intake valve, exhaust valve or rings. You really wouldn't even need a fancy tester, just introduce air pressure to the cylinder and listen for the leaks: breather means rings, tailpipe means exhaust valve and carb means intake valve. It is quick and easy to weld a male air fitting to a broken out spark plug.

simplyconnected
05-12-2014, 08:35 PM
Dave,

Do you find it unusual that the readings went up so much when he sprayed oil in the cylinders. I would think a rebuilt engine with less than 7000 miles would not show that much of a difference.

JohnThat is very typical, John. At the engine plant, they use the thinnest oil in cylinders before cranking the engine because they want a good spread. Heavier oil tends to seal valve seats as well as ring gaps, albeit temporarily. Valve seats have a huge area compared to ring end gaps.

Really, the only place to use heavy oil is in areas where excessive heat thins out the oil, like in diff's. New Ford engines specify 5W-20, and you know how thin trans fluid is. - Dave

topdeadcenter
05-13-2014, 08:56 AM
I will go digging for the receipt tonight. (I have a 2.5 inch thick binder of receipts) I don't recall it having many specifics on it, though. I think I am going to pop the valve covers off this weekend if I can make some time.