Automatic Transmission Issues

[mtrehy]

Hi All,

I hope everyone is well!

I'm restoring a 63 Avanti in the UK. Engine is R3 clone, heads, intake, etc with an Edelbrock 1406 carb. I have just refitted the engine after a full rebuild and having problems with the powershift transmission. 

I have the car in the air and it will select reverse and the wheel speed seems to increase relative to engine rpm. The first few times I selected drive nothing happened, the rear wheels have now started turning in the right direction but certainly slowly and not increasing at all in relation to engine rpm. oil level is good. 

Automatic transmissions are not my forte - I have the workshop manual.

Would be grateful for any pointers. 

I have no way of knowing whether the transmission was ok previously (deceased estate). I do have a spare but likewise of unknown history/condition.

 

Thanks in advance!

 

 

 

 

[dynolou2]

Did you check the fluid per the manual? with a helper in the car foot on brake in drive, then you check level.  Lou Cote

[mtrehy]

Hi Lou,

 

Not really! I did it with engine hot and running in park. went up and down through the gearbox several times but checking in Park.

 

Strangely if you read the manual the section "When and how to check fluid" gives your method, but the next section "When and how to change fluid" says to do it in N but I suppose it is more accurate with the volume.

I'll try it in D and see what happens. From what I've read adjusting the rear band seems simple and doesn't require dropping the oil pan, also can check the throttle linkage. I'm hoping one of these sort it out!

 

Thanks

[mfg]

Hello mtrehy, You may indeed need to drop that trans oil pan.....What you find in the pan will probably indicate the condition of that Powershift.

If you find the pan to be relatively 'clean', dropping the trans valve body for a thorough disassembly and cleaning may just do the trick.

If the pan if full of 'goo', burnt fluid, and small pieces of clutch lining material, it may be time for an overhaul.

[mtrehy]

On 9/12/2018 at 12:58 AM, mfg said:

Hello mtrehy, You may indeed need to drop that trans oil pan.....What you find in the pan will probably indicate the condition of that Powershift.

If you find the pan to be relatively 'clean', dropping the trans valve body for a thorough disassembly and cleaning may just do the trick.

If the pan if full of 'goo', burnt fluid, and small pieces of clutch lining material, it may be time for an overhaul.

Hi,

I dropped the pan and removed and thoroughly stripped and cleaned the control valve assembly and reinstalled. It wasn't particularly clean in there but nothing I would have described as horrific.

At the same time I adjusted the front and rear bands.

It's still not right though. Car is on axle stands. It seems to act normally in Reverse and 1, but 2 and D need a load of revs to get the wheels to turn. I played around with the rear band adjustment and it doesn't seem to make any noticeable difference 1 whole turn either way.

I'm pretty much out of ideas now. 

Another problem, but hopefully simpler is that I am finding it very hard to adjust the gear change linkage so that I can get both Park and 1 (the 2 extremes). If I adjust the rod so I get park then I can't get 1 and vice versa..... 

Is it overhaul time?

Thanks

 

[mfg]

20 hours ago, mtrehy said:

Hi,

I dropped the pan and removed and thoroughly stripped and cleaned the control valve assembly and reinstalled. It wasn't particularly clean in there but nothing I would have described as horrific.

At the same time I adjusted the front and rear bands.

It's still not right though. Car is on axle stands. It seems to act normally in Reverse and 1, but 2 and D need a load of revs to get the wheels to turn. I played around with the rear band adjustment and it doesn't seem to make any noticeable difference 1 whole turn either way.

I'm pretty much out of ideas now. 

Another problem, but hopefully simpler is that I am finding it very hard to adjust the gear change linkage so that I can get both Park and 1 (the 2 extremes). If I adjust the rod so I get park then I can't get 1 and vice versa..... 

Is it overhaul time?

Thanks

 

.....GOOD MAN!....dis-assembling those control valves for cleaning takes patience....I applaud your efforts!

Is it time for an overhaul?....myself, I'd actually try to drive the car to see how it behaves on the road, all the time SHORTENING the throttle control rod (if the trans seems to need higher than normal RPM's to upshift.

Anyway, it sounds like you're making progress!

As far as the trouble you're having 'catching' both park &  1, that has to be wear in the shift linkage itself..... (sometimes the holes get 'oval shaped'.....It shouldn't be an internal transmission problem.

 

 

Edited September 15, 2018 by mfg

[dynolou2]

Not having the P and 1st adjustment means that a grommit in the linkage is worn out, on the Avanti it is at the shifter end of the rod. In the SI catalog part # 1539489, insulator, shift lever.  Lou Cote

[dynolou2]

Not having the P and 1st adjustment means that a grommit in the linkage is worn out, on the Avanti it is at the shifter end of the rod. In the SI catalog part # 1539489, insulator, shift lever.  Lou Cote

[dynolou2]

As Jaguar used a simular version of this trans, parts for it and repair experts should be available in the U.K...  Lou Cote

[mtrehy]

Thanks all!

My next plan was to drive the car and see if it performs differently with load on it etc. When you say "shorten the control rod" I assume that you mean the rod at the bottom of the engine block that connects the throttle linkage to the transmission? How I set this up was to set the throttle linkage in the engine bay with a 17/64 gap (as per the manual), with the pan removed I adjusted the rod so that the clevis dropped perfectly into the throttle linkage hole with no pre-load on the control arm. I assume that by shortening the rod I would be tricking the transmission into thinking that the throttle was opened more than it actually is.

the grommet in the gear shifter is in a pretty sad state - I had thought that was a likely issue. I will turn up a nylon bush for the moment and get the correct grommet ordered.

Thanks for the tip RE Jaguar transmissions. A very good friend of mine will definitely know somewhere to get the box overhauled if necessary.

One question though - I installed the engine and transmission as a complete assembly. How much of a nightmare is it to remove the transmission on it's own with the car on stands? It doesn't look much fun....

cheers!

 

 

[mfg]

There's 'just' enough clearance to sneak that transmission out from under the car...."JUST!".....The X-member makes it tough!....On the install, saw the heads off two 7/16" x 4" coarse thread bolts installed in upper converter housing holes to aid in alignment.

[dynolou2]

In order to properly set throttle pressure you need to set it following the book, with a pressure gauge. Had an owner complain, no passing gear. Installed gauge power brake in Drive to 1500 rpm , it only showed 70 psi.  It took about 8 turns of the adjusting link ( shorter ) to get it within the 80 to 85 psi. Lou Cote

[mtrehy]

Hi,

 

I got it off the ramp and outside and definitely very wrong! Extremely jerky and then locks completely after 20 metres going forwards. Strangely it seems ok in reverse.

I have a spare transmission - it's not got the same green data label as the original one - can anyone confirm what ths spare transmission is and whether it would be ok on the Avanti? I don't know it's history so could easily not be any good either.

 

Any help greatly appreciated!

[mfg]

Wow!...VERY strange!..... the transmission shift control lever (on the left side of the case) is the type used with a FLOORSHIFT CONTROL....indicating an Avanti Powershift transmission,..... however, the case has a dipstick /filler tube (for underfloor fluid checking) that was last used in '60/'61...indicating it CAN'T be an Avanti Powershift unit!!!

The white background on the serial tag is normally found on '56-'64 'normal duty' V8 Studebaker Flightomatic transmissions.

Frankly, I don't get it!

 

Ah-Ha!!...... I just noticed the odd bracket attached to the left side of the transmission under two extension housing bolts.....Did this trans come out of a RIGHT HAND CONTROL Studebaker?....That might explain the Avanti-style shift lever!

[mtrehy]

Part of the deceased estate included a RHD Hawk. might be related to that..?

Any idea whether it would go on the Avanti? I assume I could swap the sumps and use the oil filler on the existing transmission....

 

thanks

[mfg]

1 hour ago, mtrehy said:

Part of the deceased estate included a RHD Hawk. might be related to that..?

Any idea whether it would go on the Avanti? I assume I could swap the sumps and use the oil filler on the existing transmission....

 

thanks

Not really!,....yes, you could swap around transmission pans, but that Hawk Flightomatic transmission, although it externally looks about the same as an Avanti Powershift, is quite different internally.... The biggest difference being the shift pattern (PNDLR) as opposed to PRND21....the valve bodies, and a few other internal parts, could be swapped around to correct this, however, it has none of the heavy duty components (clutch plates, bands) which are in an Avanti Powershift (or even the heavy duty version of the Hawk Flightomatic.

Also, the Avanti Powershift transmission has an external water cooling feature that isn't found on that 'normal' duty Flightomatic transmission.

I think I'd try to sell off that Hawk Flightomatic (they seem to never go bad!) and put the $$$$ into a rebuild of your Avanti's original trans.....Ed

[Chet Gorgas]

I have the Flightomatic with shift pattern PNDLR and it starts of in D (2nd) but will not shift when you get the car going; I am of the belief that the tranny will shift to a cruising speed but does not. Thus , I can't really drive the car much beyond 30mph as it is too hard on the engine.  I figure there is probably an adjustment required and coordinated between the throttle control and pressure control rods. Help with "how to" is appreciated. Thanks, Chet SDC #068621G

[mfg]

1 hour ago, Chet Gorgas said:

I have the Flightomatic with shift pattern PNDLR and it starts of in D (2nd) but will not shift when you get the car going; I am of the belief that the tranny will shift to a cruising speed but does not. Thus , I can't really drive the car much beyond 30mph as it is too hard on the engine.  I figure there is probably an adjustment required and coordinated between the throttle control and pressure control rods. Help with "how to" is appreciated. Thanks, Chet SDC #068621G

Yes, your Flightomatic is a three speed transmission  that should upshift from '2nd', where it starts( in drive), to '3rd' at around 15-20 mph. (light throttle)

If it's not doing that, the throttle pressure control rod may be out of adjustment and needs to be shortened.

If doing that does not help, then the problem may be a dirty transmission control valve, where the sliding valve that controls the 2-3 upshift may be stuck..

It's also possible that the governor, located via an access plate in the tailhousing of the transmission, is sticking and needs cleaning.

Dropping the trans oil pan (which you have to do to access the trans control valve) will reveal the internal condition of the entire transmission....Best of luck!....Ed

[brad]

That is not a Powershift transmission. The tag should read AS2-10A. The shift pattern of that would be P N D L R.  No second gear holding. Also if the car locks up in low it is usually because the rear sprag (one way roller clutch) ,that is located in the center carrier, has been installed backwards. The brass drag strips should face the rear of the car as installed. 

Edited July 20, 2019 by brad

[mfg]

2 hours ago, brad said:

That is not a Powershift transmission. The tag should read AS2-10A. The shift pattern of that would be P N D L R.  No second gear holding. Also if the car locks up in low it is usually because the rear sprag (one way roller clutch) ,that is located in the center carrier, has been installed backwards. The brass drag strips should face the rear of the car as installed. 

I'm pretty sure Chet is talking about a regular (non-Powershift) Studebaker Flightomatic here Brad......I guess they couldn't help him over on the SDC Forum!