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Still working on the tranny in my '50 Super DeLuxe 8... The torque converter has now been replaced and the transmission is rebuilt. Before, it wouldn't take off in "H" seemed too weak to do this. Now it seems there is a 'delay" after sitting say over night. When you put the car in "H" it takes a while to go into gear. I don't know how long a delay, but the shop doesn't feel the car is right so it is there still. Anyone know of something that would cause this? Is it like a problem that the "ABC gizmo" caused and there is a service bulletin that specifically addresses this??? (I hope!!) Just asking...

Nothing I see other than the one referenced before about the pump relief valve spring issue causing a delay.

Might be nice to have some idea of length of delay and if your mechanic ever did any pressure tests. That still seems to be the best suggestion at this point to find the areas to look in. Maybe Ross will see your question if it stays visible and have a suggestion.

It should be fairly instant. Mine was slow to engage when i had low pressure from everything being wore, or wouldn't engage until you pick up some RPMS.

If they're not doing much or giving much info, you might be better off to get it home and start doing diagnostics yourself.

Howard, the transmission guy knows about the relief spring as I printed out that whole thread and faxed it to him. So I am guessing that has been eliminated as a possible cause. I was told the valve body was pulled several times today. I am thinking they feel the problem lies in that area. Thanks for the feedback, if you have an ahh hah!! moment, let me know!

Delay could be due to a leaking seal in the piston or servo or what ever it is that applies the "H" range clutch.

A short delay after sitting overnight is usually caused by the convertor draining back into the tranny. It takes 10-15 seconds to fill it before you "get a gear". There is nothing tragic in this--but a freshly built trans should not do it.

The other cause for delay in a 49-54 is leaky seals in the low and reverse servos. They can look perfect, but if they are a little hard they will leak enough to cause a pressure loss that will delay the high clutch engagement--even though they are not being specifically used in "H". The high clutch itself has a cast iron piston ring, so is not usually a problem unless broken during reassembly.

It is very easy to change the servo seals with the pan off, and without having to remove the valve body.

To Ross,

A thought on low/reverse servos affecting high range engagement. When shifted into H, I don't think there is any pressure being applied to low/reverse servos so therefore there wouldn't be any leak/pressure loss. Would it be a good way to test if it is converter leakdown by shifting into Low immediately after starting and see if there is a similar delay?

I had thought that grinding off the check valve thingy-magic per the service bulletin would allow the converter to drain back some and that's why they said to check fluid within one minute of shutting off after that change, vs the 5 minutes as earlier specified.

If you modify that valve per the counselor (as i believe Paul's has been) could it be a side effect that you'll need a 10-30 second delay before using the car after sitting over night? I don't think that's terrible at all IF that check valve is actually the problem and packard recommended removing it anyway.

Edit: I guess the test would be fire it up and run it for a few minutes. Then shut it off, and wait a minute, and if the delay isn't there anymore but IS after waiting overnight again, you'd know right off it's related to converter filling/leakdown?

Hey Fred: In the early ultras, the servos are pressurized even when they are not in use so as to hold them in the off position. That's why they are a potential problem.

You are correct that a good way to check for convertor drainback is to select L or R immediately upon starting and see if they also have delay.

This is a tough problem because the Packard manual doesn't have a symptom "delayed high range engagement"

I have heard of UM's having this problem and then it just disappears for some unkown reason.

Why not do a compression test and make sure you have at least 100 psi.

Then hook up a tach and check the motor speed during full throttle acceleration.

If you have high range clutch leakage the RPM will be over 2000.

This is easier than pressure gauges because - quite frankly - checking line pressure in the UM sucks