Transmission problems

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Transmission problems

Post by 65CherryMonza »

First of we have been enjoying our Corvair greatly this summer it was a blast cruising around with the whole family. Maybe we get a couple more days out of this year... 

So to my question yesterday I went for a drive about 20km or so on my way back I stopped at a store. When I went back on the road my transmission wouldn't shift from first to second without being stuck in neutral for a bit what caused to rev the engine...

Any idea what that could be ? I still have the issue where when you shift into drive you have to push down a little further towards L for the transmission to shift into gear... No problems in reverse but drive is a bit hard to find... It was like this from the day I bought it but now they neutral slip is worrying me a bit. 

Any suggestions are welcome ! 

1965 Corvair Monza Coupe 110 / Powerglide transmission

Thanks guys !
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Re: Transmission problems

Post by terribleted »

Manual valve (throttle valve) out of adjustment is likely the shifter wiggle issue. Get out the shop manual and purchase the special tool, follow the instructions, remove the pan and adjust the valve, reassemble.

For the engine speed flares on upshift issue the list in the 1961 Corvair shop manual, (do not know why this was not included in the 65 book as the transmissions are the same), says (I posted these in order of ease of checking):
1. Low fluid level
2. Collapsed vacuum modulator hose or faulty modulator either joining hose at modulator or balance tube could be blocked.
3.Clogged trans filter screen
4. Blocked high clutch feed orifice
5. Clutch plates worn
6. Clutch piston stuck
7. Clutch seals leaking
8. Clutch drum relief ball not seating

I would certainly adjust the manual valve (might influence the slipping issue ?) and clean the filter screen while I was in there, and of course check the fluid level (at full mark on check stick while warm and idling in neutral) and condition of the vacuum lines going to the modulator. Make sure there is no transmission fluid in the vacuum line to the modulator. If there is the modulator diaphragm is bad and the modulator should be replaced.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.

Located in Snellville, Georgia

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Re: Transmission problems

Post by joelsplace »

The manual valve being way off can certainly cause slipping issues. One thing you can try is disconnecting the vacuum line to the modulator. Plug the engine side. Unlike some other transmissions it only changes the shift firmness not the shift points.
113 Corvairs, 5 Ultravans and counting
Northlake, TX

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