KCguy

Hi, new here. I have a 1951 Super 88 that I am finally getting back on the road. The car sat for probably 15yrs since the last fluid change. After working on the engine, brakes, fuel delivrery and front end after having sat in storage I get around to taking it for a drive down the street and it upshifts slow and downshifts late. I decide to pull it back in to change the fluid and clean the valve body. As I back it out one more time it doesn't return to drive. Just reverse. No drive. I drop the pan clean and inspect the valve body, clean screen and refill, same problem only this time car will not roll in neutral. Drive acts as though it's still nudging back a bit. What component/s did I overlook for cleaning/ inspection? Rear servo?

Any help is greatly appreciated.

Thanks

d2_willys

You may have stubborn front servo. With engine off, the front band is holding the front planetary in reduction. When engine is started, the front band is released by the servo. (Servo does not apply the band, spring applies it). It may be as simple as dropping the pan and seeing if the band linkage and servo are free to move.

My 54 Lincoln did the same thing years ago one day. I tried shifting back and forth, with only reverse working and the transmission having a noise in drive ranges. I checked the fluid, and it was low, so I put another quart in and let the transmission cool down, presto, hasn't given me any more problems.

You can also remove valve body and shoot compressed air into clutch and band ports and see if all is functional. If so, go back to valve body and check carefully.

One more thing, is the parking pawl releasing in neutral and drive ranges? This may be the problem.

KCguy

Hi, thanks for the input. How do I check if the parking pawl is releasing? When off it acts as though it's in gear even in neutral. (tried to push it in the driveway w/ no luck) I disconnected the linkage and manually shifted through the gears on the tranny. Still locked up.

d2_willys

The parking pawl can be accessed by removing the side cover. It will be toward the back of the transmission. If this is stuck in Neutral and drive ranges then no drive or pushing the car in neutral.

Do you have any manuals on the transmission?

The parking pawl mechanism is released by oil pressure when the car is running, or when in anything but reverse. Reverse with engine off is equivalent to a parking gear.

KCguy

Manuals... yes. I've got plenty; a factory 50-51 manual and a trans only manual which appears to be the 50' and earlier hydramatic. 51 being the same except a few changes. The troubleshooting section left me scratching my head.

I'll look up that parking pawl. I avoided taking it off when I removed the valve body. Unrelated ( I think) I notice a spring missing on the middle govenor plug in the body according to the diagram. (named the "number 1 govenor plug spring") Just curious if that is note worthy.

d2_willys

U R refering to the G-1 spring, which is used for the 1-2 shift. The G-2 spring is used for 2-3 and 3-4.

I just thought of something. My 50 Olds 98 always starts in 2nd. That might be what is missing! It would probably start in 2nd all the time without that spring.

That would not keep the trans from working in neutral and drive. I will look in my books and try to pinpoint some posibilities.

KCguy

well, so far parking pawl seems to be working fine. I think one of the bands isn't releasing. Trying to figure out which ports to hit with compressed air.

KCguy

Got the ports sorted out to check with air. Bands are releasing. Clutch ports make a air pop noise when air applied. Seems like the servos may be ok.

d2_willys

Apply air pressure to the reverse apply port too. Make sure it is releasing.

I think the reverse unit is hanging up! That is what the diagnosis chart says about not having drive after being in reverse range.

HMdiagnose1.jpg

HMdiagnose2_.jpg

HMdiagnose3_.jpg

KCguy

Update: Pressure regulator checked, valve body rechecked. I had assembled one govenor valve backwards so I skipped taking apart the parking mechanism to try it again. Same result; reverse but no forward. I believe I need to take apart the reverse tailshaft assembly. I couldn't find the port listed in my book to check the reverse cone clutch.

d2_willys

I have attached a pdf that lists the problem with the reverse clutch sticking. I believe this is what is happening. It lists how to free up the clutch without dismantling. It also lists how to burnish the clutch to prevent this from happening.

hydramatic ports.jpg

hydramatic reverse hangup.jpg

Above are the reverse port locations in the next image:


IIRC, the procedure for freeing up the reverse clutch was what I did (accidently). Try it and see if this at least gets the forward ranges back.

KCguy

Hey, those images are coming in the size of postage stamps. Can you resend?

That is exactly the info I'd like to read!!! My manual is confusing as some of 50' model info. and procedures is relevant and other 51' model info is appended. I found the part that said "refer to manual for burnishing the reverse cone" but couldn't locate the procedure!!

Thanks again!

d2_willys

Just did. Had a problem with the attachement thingy. If you want to save the images, just click on them till they open up, then copy to clipboard and then to paint. Should be able read them after that.

Here are bigger pics:

G-DualRangeHydramatic0022_jpg.jpg

G-DualRangeHydramatic0103_jpg.jpg

KCguy

THANK YOU. This is good timing as I was ready to take this thing apart again!!

Man, they are serious about man handling this transmission into shape!! HA.
I think I can handle that. Good thing I just replaced the rear motor mounts. I found that the motor mount was literally sitting collapsed metal to metal on itself!!!

d2_willys

Yeah, I just stumbled onto fixing it, by getting pissed and revving the engine up between reverse and dr. Must have gotten stuck years ago on my Lincoln. Hope all this helps you out. I need to keep that page handy for all my hydros! Don't think the procedure works on 50 hydros as they had mechanical clutch.

Here is the link to the hydramatic stuff: http://www.cogpro.com/chapters/G-Dua...atic/index.htm

KCguy

So glad to find this forum. I'll give it a try tonight and will check back in here. Thanks for all your help.

KCguy

update: I'm still stuck fighting reverse. Back to no pushing the car in neutral w/ engine off. Rpms lug down as if under load in DR but no movement. Neutral idling, car edges backward a little. I'm researching more before pulling this thing apart again.

d2_willys

I will keep on looking into this issue. Guess u tried the Reverse to Drive with engine revved up thing. Says to only do this 5 times max.

Maybe there is a way of releasing the clutch without removing the whole damn thing. You might be able to remove the extension housing and get to the reverse clutch that way.

Can't remember, but wasn't this car sitting for awhile? Maybe rust set in on the reverse clutch.

Does your transmission try to grind when going into Reverse? Do you know if this is a late model 51 hydro. The early 51 hydros were mechanical engagement, not hydraulic.

I will look in my books and see if there is a way of getting to the reverse clutch without dropping the trans.

KCguy

Yes, I tried the back and forth procedure with no budge. Reverse works beautifully. No grinding. Honestly it sounded as though it shifted from rev. to low just once. In neutral idling I can't push the car forward... it wants to drag and edge backwards. DR drops rpms down like it engages (slight kick backwards) then no budge (engine under load)

Not sure if it's early or late 51' It was sitting for a long time and before that I never drove it that much. (always working on the engine) It's a mild built up 303.

I'm thinking I need to drop the parking assembly, front & rear servos and check them out. Them maybe the reverse tail shaft assembly.

d2_willys

Honestly I would start with the reverse clutch. That thing is hanging big time! Like I said, if you can get to the clutch from the rear after removing extension housing, you might just get it unstuck. Would hate for you to take the rest of it apart if it just the reverse clutch.

From what you said, it sounds just like what mine did years ago.

See how hard it is to get to the reverse clutch before doing any other work. Might not be to hard to get to it.

KCguy

Almost a year later discovered tonight problem:

> Throttle rod out of adjustment < After several valve body tear downs (last fall) I discovered tonight that the TV rod was way to low. (thanks FATSCO) Not sure why it worked before. I suppose the rear motors could have thrown things off. I've had the linkage off a few times after rebuilding the carbs. Maybe I threw it out then. After tightening it towards carbs, I now have drive gears. Still needs adjustment but at least it's shifting now. Anyway, thanks for all the advice and spec sheet.

47 Coupe

47 Coupe; I need to change the 47 flathead 6 Hydra-matic drive motor mounts. it looks that it has only two mounts. A front and one rear near the transmission. Does one have to pull the engine and transmission or just unbolt the mounts and jack up the engine and transmission? I'm unknowing I would appreciate any assistance. Thank you.

KCguy

I'm not sure for a 47' six, but on the v8 I was able to use a block of wood and a floor jack under the front of the engine (be careful not to collapse the oil pan) and raise it enough to unbolt and replace the mount. Same with the two rear mounts on the transmission. In this case I placed the jack directly under the flat part of the bellhousing and raised. If you have an engine hoist you could lift from above if it clears the hood.

Also, having a large tapered alignment pin (or punch) helps to align the mounting holes while you thread the bolts.

hope that helps