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PG Transmission Woes
Posted by: hydroman ()
Date: September 04, 2020 09:48AM

I am stumped. ATF oil level is fine, the manual valve linkage has been adjusted. Checked modulator for oil, still no luck. The transmission goes into gear and the car moves. Reverse is a little delay to engage. In drive I can only go about 10 mph, any faster the car has an issue going forward. The transmission is a rebuilt from Clarks, differential is from California Corvair. When I first drove the car for the first time, everything appeared fine for about 2 mile of travel. Then the problem started. Anyone from the Sacramento area want to make a field trip, I would appreciate the help.

Bob Burrell
1968 Monza Convertible
140 (110 with 140 heads)
PG (ID: AF)
Yuba City, Ca



Edited 1 time(s). Last edit at 09/04/2020 11:48AM by MattNall.

Re: Transmission Woes
Posted by: Wagon Master ()
Date: September 04, 2020 10:35AM

Did you do the shim setup procedure for the governor gear?

'29 Ford Model A Tudor
'61 700 Lakewood 110 4 speed
'69 Monza Convert. 140 Auto.
'70 Dodge Challenger R/T 440 4 speed

Been aircooled since 1973
Northwest Ohio

Re: Transmission Woes
Posted by: hydroman ()
Date: September 04, 2020 11:22AM

Yes

Bob Burrell
1968 Monza Convertible
140 (110 with 140 heads)
PG (ID: AF)
Yuba City, Ca



Edited 1 time(s). Last edit at 09/04/2020 11:23AM by hydroman.

Re: PG Transmission Woes
Posted by: Layton Curtis ()
Date: September 04, 2020 12:36PM

Take a look at the governor.

Re: PG Transmission Woes
Posted by: hydroman ()
Date: September 04, 2020 12:51PM

What would I look for? I replaced the nylon gear yesterday. Have no leaks.

Bob Burrell
1968 Monza Convertible
140 (110 with 140 heads)
PG (ID: AF)
Yuba City, Ca

Re: PG Transmission Woes
Posted by: isucorvair ()
Date: September 04, 2020 01:01PM

Where did you get the Torque Converter?

Are you checking the transmission fluid with the engine / trans up to temp?


Eric P.
DeWitt, IA

Re: PG Transmission Woes
Posted by: davemotohead ()
Date: September 04, 2020 01:06PM

Sounds like the front pump is not making any pressure, the way these things work is there are 2 pumps, the front pump runs off the crank and is used for slow speed driving, it provides the trans pressure for getting started rolling and reverse, after the car reaches about 30 MPH or so the rear pump (runs off wheel speed) makes pressure and a valve opens that now runs the car off the rear pump that runs off wheel speed, basically the diff. Could be the C clip fell off the the triangle pump drive washer in the front pump, or the splines are stripped on the pump rod, The best way to check it to put it on a lift and put a gauge on the test ports on the front pump housing, the Procedure is in the manual.

Also the shim adjustment is to center the entire running assembly in the transmission between the front thrust washer and the governor gear, it centers the entire assembly to align the pumps and control the fore / aft movement of the trans internals, this measurement and adjustment must be done any time you change a PG or diff as the measurement will be different when ever one of the 2 components are changed, Even if you did not do this or did it wrong I do not think it would cause the problem you are having in the 2 miles you have driven, it causes running problems after miles are put on the new trans.

Edit to add: The governor only controls the shift point speed and will not cause this problem, also the engine and trans do not need to be up to temp to check the fluid level, you check the level with the engine running in neutral.

Edit #2, also if you look at the pic I posted, at the bottom right there is a little valve sticking out, if this valve was left out of your rebuild it will also cause this problem, I found a clarks rebuild where they left the valve out.







1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)

-----------------------------------
Rust Free Lancaster Ca



Edited 2 time(s). Last edit at 09/04/2020 01:12PM by davemotohead.

Attachments:
Re: PG Transmission Woes
Posted by: joelsplace ()
Date: September 04, 2020 02:09PM

You guys are good. Did I miss another post on this car that gives more information?
This is all it gives us for symptoms "Reverse is a little delay to engage. In drive I can only go about 10 mph, any faster the car has an issue going forward."
I'm not a mind reader. Does it take off in 2nd gear? Does it bind up? Does it freewheel? Does it just quit? ???

Joel
Northlake, TX
5 Ultravans, 113 Corvairs and counting...

Re: PG Transmission Woes
Posted by: hydroman ()
Date: September 04, 2020 02:24PM

Clarks

Bob Burrell
1968 Monza Convertible
140 (110 with 140 heads)
PG (ID: AF)
Yuba City, Ca

Re: PG Transmission Woes
Posted by: hydroman ()
Date: September 04, 2020 02:38PM

When I said delay in reverse, its just not immediately. It does go into gear and appears to be working fine. It appears to be working fine when I start driving.
After traveling about 500', it doesn't want to accelerate. It's almost like it doesn't want to changes gears.

Bob Burrell
1968 Monza Convertible
140 (110 with 140 heads)
PG (ID: AF)
Yuba City, Ca

Re: PG Transmission Woes
Posted by: joelsplace ()
Date: September 04, 2020 02:41PM

"doesn't want to accelerate"
That describes an engine problem.

Joel
Northlake, TX
5 Ultravans, 113 Corvairs and counting...

Re: PG Transmission Woes
Posted by: hydroman ()
Date: September 04, 2020 02:50PM

Engine runs fine. Adjusted the carbs today.

Bob Burrell
1968 Monza Convertible
140 (110 with 140 heads)
PG (ID: AF)
Yuba City, Ca

Re: PG Transmission Woes
Posted by: Marco_a_p ()
Date: September 04, 2020 03:11PM

Had a problem car come into the shop one time with simialar symptoms.
Owner had changed out the Modulator Valve. So we started there.

Removed the Modulator valve and found that the piston that the valve actuates in the trans was missing. Pulled one from a used trans. Issue resolved. In that case the motor could rev up to redline and car would barely move along, maybe 5 mph

I disagree with that statement about the front pump though. That car would not move at all if the front pump is not working. Fixed many sheered 3 Tab washers and some that had their splines stripped out. In all cases, there was no forward motion at all.

But if its getting up to 10 speed and feeling like is not shifting up to 2nd, wouldn't that be low main line pressure which would the a rear pump issue?

Where's that GM Corvair PG Troubleshooting pamphlet?

Marco
A 2nd Gen Monza Wagon, a 2nd Gen GB 8door, a 2nd Gen (61's were 1st Gen) R/s and a 62nd Gen Turbo coupe..

Hanging out with the scorpions, king snakes, road runners, coyotes and quails In the southern desert of the silver state
Mesquite NV 89024



Edited 1 time(s). Last edit at 09/04/2020 03:14PM by Marco_a_p.

Re: PG Transmission Woes
Posted by: Lane66m ()
Date: September 04, 2020 03:13PM

Does the engine accelerate when you push the accelerator, but it doesn't go any faster on the road? (engine revs up but no more forward speed acceleration?)

What is the top speed you get out of it?

What is the fluid level right now?

Al
Georgia

Re: PG Transmission Woes
Posted by: hydroman ()
Date: September 04, 2020 03:31PM

Engine revs up but no more forward speed acceleration. Fluid level is full. The engine does accelerate, but doesn't go any faster. I'll take it out when my son gets home and do a video.

Bob Burrell
1968 Monza Convertible
140 (110 with 140 heads)
PG (ID: AF)
Yuba City, Ca

Re: PG Transmission Woes
Posted by: Marco_a_p ()
Date: September 04, 2020 09:37PM

Question: When checking the fluid level was it done with engine running?

Question 2: When you check fluid level BEFORE starting the engine is the fluid level high on the stick? Then when you check with engine running, dose it drop down to the full mark?

Marco
A 2nd Gen Monza Wagon, a 2nd Gen GB 8door, a 2nd Gen (61's were 1st Gen) R/s and a 62nd Gen Turbo coupe..

Hanging out with the scorpions, king snakes, road runners, coyotes and quails In the southern desert of the silver state
Mesquite NV 89024

Re: PG Transmission Woes
Posted by: hydroman ()
Date: September 06, 2020 11:11AM

Before I started the engine today it was high. After it ran for about 30 minutes the level didn't change, car was running.

Bob Burrell
1968 Monza Convertible
140 (110 with 140 heads)
PG (ID: AF)
Yuba City, Ca

Re: PG Transmission Woes
Posted by: davemotohead ()
Date: September 06, 2020 11:38AM

hydroman Wrote:
-------------------------------------------------------
> Before I started the engine today it was high. After it ran for about 30 minutes the level didn't change, car was running.
-------------------------------------------------------
That is a sign the front pump is not working, When the fluid level is full with the engine running, the front pump is pumping the fluid through the trans, the running full mark is that way to have correct running level, when the engine is shut off the fluid returns to the pan and makes the level go up, that is why you do not check the level with the engine off, if the level is high on the dip stick and does not change when the engine is running, the front pump is not working or that little Valve I showed you is not there, I have seen the C clip come off the Triangle drive washer and the splines on the shaft strip, it will do just as you said happened, it will run slow and eventually wont run at all as the splines are continuing to slip until they are gone, also could be the other end of the shaft in the TC is stripped, the first step should be to put it on a lift and check the trans pressure at the check ports as described in the manual, but my bet is the front pump has a problem some where.







1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)

-----------------------------------
Rust Free Lancaster Ca

Re: PG Transmission Woes
Posted by: Timothy Shortle ()
Date: September 06, 2020 11:44AM

Are you able to hook up a pressure gauge and check pump/line pressure? I suspect it will be very low.

Re: PG Transmission Woes
Posted by: hydroman ()
Date: September 06, 2020 11:49AM

I will be able to do that. Will go pickup the gauge from my son in law. Will post with the results later today.

Bob Burrell
1968 Monza Convertible
140 (110 with 140 heads)
PG (ID: AF)
Yuba City, Ca

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