Transmission Doesn't Shift

[Alexander]

RE: What Model Transmission?

Yes, you must stop fully before changing directions or your transmission case will crack. If you follow this rule, your cruise-o-matic will give you decades of good service.

I guess this transmission problem on Squarebird prevented it from being selected as the General Lee Car on the Dukes of Hazzard.

http://www.squarebirds.org/images/general_lee.jpg

Alexander
1959 Hardtop
1960 Golde Top

[peeeot]

RE: What Model Transmission?

Based on your rendering, Alexander, I'm sure it wasn't the visual appeal that kept it from being selected :P

I bet some previous owner cracked the case in exactly the way you guys described. MOST people I ride with do not stop their vehicles completely before shifting out of reverse. I've never understood why. Oh well... I guess as long as the transmission works okay, I'm not going to worry about it!

Any thoughts on the weird front clutch test behavior?

[peeeot]

RE: What Model Transmission?

A closer look at some of the illustrations in the manual suggest to me that the crack I found in the case is not in the vecinity of any fluid passages. As far as I can tell, the repair that has already been done MAY be adequate indefinitely.

My shift points are still off though. Today they were high again, closer to how they used to be. There is some slop in the pivot point of the accelerator linkage on the intake manifold that has made it difficult to adequately set a starting point for the throttle linkage adjustment for the transmission. I know that shortening the connecting rod decreases control pressure, and lengthening it increases pressure.

If shift points are high, is pressure most likely to be low or high?

[peeeot]

RE: What Model Transmission?

I've tried adjusting the throttle linkage in both directions and it made no difference in how the tranny shifted.

The way I see it, one of 3 things must be going on: either the control pressure is too low, the 1-2 shift valve is sticking, or the governor valve is sticking.

The strange behavior of the front clutch in the air pressure test has me concerned that there is a pressure leak somewhere that is resulting in inadequate control pressure to the governor, but I can't be sure yet. What I DO know is that immediately after "refreshing" the governor, the car shifted much better, and after sitting only a day or two the shifting has returned to its original state. This is the same thing that happened after my mechanic messed with it and supposedly cleaned up the governor.

So to start I'm going to pull the governor again and inspect it. If it is sticking/rusty again after being cleaned thoroughly only a couple of days ago, then something is wrong with the fluid getting to the valve. If it doesn't have fluid in/on it, of course it will rust, but it should be getting enough fluid in the right places for rust to be a non-issue.

If, however, the governor is immaculate and moves freely in its bore, then I must look elsewhere. I'm considering in this case pulling the pan again and removing the valve body and perhaps the pressure regulator and disassembling them to check thoroughly for stuck valves, blockages, etc.

If none of these efforts take care of it, I don't know what I'll do yet.

[peeeot]

RE: What Model Transmission?

I pulled the valve again today and it did not look rusty. It wasn't moving as freely in the bore as it should, however.

This time I disassembled the valve and cleaned it and polished the valve and bore such that the valve moved freely in the bore when it was totally dry, with no lubrication of any kind. I then lubed it with some tranny fluid and reassembled. The ensuing test drive was very enjoyable: shift points were a hair's breadth from spec and, perhaps more importantly, were consistently very smooth.

This gives me hope for the overall status of the transmission. Clearly, it CAN work very well without major servicing.

The test that I'm holding my breath on is whether this excellent performance will remain the next time I take the car for a drive. I really can't figure out why the valve would start sticking after only a couple days' time of disuse. Clearly fluid is getting to it, or the car wouldn't be able to drive like it did today!

So hopefully I won't have any more problems from it any time soon. I'll post as soon as I know one way or the other.

[peeeot]

RE: What Model Transmission?

I've had more time to evaluate this. The past couple of times I've driven my car, the shifting is way off until the transmission warms up, at which point the 1-2 shift is a bit late and the 2-3 shift comes right on the other shift's heels. I've had more than one occasion where the trans slid through second into third in one smooth, but abnormally long, shift.

Every time I've pulled the governor and cleaned it, shifting has improved. Does any one have any idea why the shifting could detriorate from one drive to the next?

[Guest]

RE: What Model Transmission?

Perhaps your transmission is full of old cruddy transmission fluid....or build up.....and everytime you drive it loosenes up more and more. Did your car at one point sit for a long time???

[byersmtrco]

RE: What Model Transmission?

You need a new transmission

[peeeot]

RE: What Model Transmission?

hahahahaaaaaaa, not what I want to hear!! :P

I think the car did sit for a long time. I don't know when or for exactly how long, but the plate that was on it when I bought it expired somewhere around 1994, as I recall....

The engine wasn't assembled when I bought it and was full of sludge and muck and who knows what else. All this to say, it could have been sitting quite a long time.

As for the transmission, when I took the pan off to replace the filter, everything was very clean. It looked like it had been rebuilt not long ago in its service life. There was also some damage to the case, which I mentioned earlier in this thread, methinks.

The fluid in it, which was and still is Dexron 3, was a good red color but there were a few little blob-like deposits in the pan. I don't remember them well enough to describe them better than that. The pan did not have a magnet in it, whatever that may suggest.

After cleaning the governor valve, the car shifts like it's supposed to. After not driving for 2 weeks, next time I drive the shifting is worse.

Why do you say I need a new transmission?

[byersmtrco]

RE: What Model Transmission?

I mean to say, yours just needs to be gone thru. Find a good tranny guy and just have him go thru it. Re seal it. Get an overhaul set with new plates (steel & fiber) Repl the Tq/Converter. MAKE SURE you remove the radiator and have the trans cooler cleaned out. Clean the lines out too and have em boil out the radiator while your there. I'm sure your trans is just gunked up. I'll bet you could do the whole deal for under a grand (Not counting R & R)

What area are you in?

John

[peeeot]

RE: What Model Transmission?

I'm in the Raleigh, NC area.

Are these transmissions supposed to have magnets in the pan?

I know my radiator is clean; it has a new core in it. The cooling lines are a different story though. They started leaking not long ago and I have ordered replacements. They should be on their way soon.

[Guest]

RE: What Model Transmission?

If your trans has shift problems and you have a crack it will not work right, these trans use pressure. My trans acted like it was truly broken then reverse went out. I use to have to find reverse. finaly it went out altogether. I got a case saver kit. The trans guy drilled the case (medium) and he put it back together and my car runs great I have driven the car 4,000 miles since, I have rebuilt the motor and my trans still works great.I do come to a complete stop before reverse and I have 130 mph power just last week.

[peeeot]

RE: What Model Transmission?

What you described is exactly what has been done to my transmission. The crack is not in a place with fluid passages. It was pulled together by drilling and tapping a whole and running a bolt through it, just like you describe. It HAS worked very well before, but if I let it sit long enough it stops working well. I know it's capable of working right. I'm trying to figure out the cause of the deterioration when not in use.

[byersmtrco]

RE: What Model Transmission?

I didn't realize you had a cracked case. Get a later model cruiso case out of a full size Ford or Merc. NOT out of another Thunderbird. 63-64 . . . That era. That's what's been in mine for 20+ years.

[peeeot]

RE: What Model Transmission?

What, did they beef it up a bit? Would the ratios be the same?

My bird doesn't have a vacuum modulator or anything, it's all mechanical. Wouldn't that introduce issues with the original linkages and all? I have no idea.