Shifting to 3rd now has problems

[PaulRV6]

On my way home from the car show my trans began to act up. This AM with 1- 1/2 hr drive everything worked fine. It shifts 1-2 where it should but now it wont shift into 3rd until the rpm is up to 3500-4000 rpm if it shifts at all. Then the boost was not raising while the rpm was going up (was this because the trans was slipping)?
What could have gone wrong? 86 GN with a shift kit installed, 750 miles since the last rebuild.

paul

 

[TexasT]

Have you contacted the builder? 750 miles isn't very far.
Could be some debris in the valve body.

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[PaulRV6]

FWIW, I was the builder. It was working great and I put a modified shift kit in it and it still worked without problems but it seemed like it gradually started to not shift properly. I checked the TV cable and all is well there, the fluid looks ok. Maybe I will check pressures and compare it to what I got after installing shift kit. Any other ideas? Thanx

paul

 

[TexasT]

Nothing wrong with you as the builder. I would definitely check pressures. If/when you drop the pan look at the 2-3 shift in the valve body. How does the fluid look? Could have a developing problem with the seal on the direct piston. Hard to know. Look into the pressure first.

Rich

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[PaulRV6]

I just tried backing out the garage and I have no reverse. I was going to take it for another test run after flexing the TV cable. It seemed like I still had forward gears but I could not move much because of being in the garage. Any ideas on this while I hook my gage up and test the pressures?

paul

 

[TexasT]

Well, if you put it together you know that the direct and the reverse is on that same piston. Are you dual feeding? Could be a cut seal, hard to know. Pressures might tell a lot.

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[PaulRV6]

No I am not dual feeding. But I will post the results of the pressure readings.

paul

 

[PaulRV6]

I checked the pressures and they all match after the modified shift kit was installed except for the reverse pressure, at idle (no TV) the pressure was only 100-120 compared to 190 psi and at full TV 1500 rpm it was only 200 psi (very erratic) compared to 290 psi before.
So what does this tell ya, anything conclusive? Is a valve not working properly or a spring gone bad? Thanks

paul

 

[TexasT]

I would think that it is loosing pressure somewhere. The piston seal on the direct would be my first guess. I'd drop it and pull it apart as I doubt it will get better on its own. If it were the low/rev piston low wouldn't work either. But you say just rev is having probs.

What are your thoughts?

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[PaulRV6]

Thanks but no, not just reverse. It started out not shifting into 3rd and then it would at a higher rpm. Then I realized rev did not work so I could back it out of the garage. Just wondering if it may be something in the valve body since I changed the shift kit not too long ago.

paul

 

[ABLACK6]

On my way home from the car show my trans began to act up. This AM with 1- 1/2 hr drive everything worked fine. It shifts 1-2 where it should but now it wont shift into 3rd until the rpm is up to 3500-4000 rpm if it shifts at all. Then the boost was not raising while the rpm was going up (was this because the trans was slipping)?
What could have gone wrong? 86 GN with a shift kit installed, 750 miles since the last rebuild.

paul

just had the exact prob and at tranny shop now, they said it's the selenoid. replacement and change tranny fluid ALL $ 340

 

[PaulRV6]

What solenoid are you referring to? I'm not sure how this would cause the trans not to shift. Thanks for the input.

paul

 

[PaulRV6]

Well I took the pan off and found nothing unusual except the fluid in the pan seemed blacker than I would have expected. Like if I rubbed my finger along the bottom of the pan it was quite black. The filter screen had what looked like copper colored speckles mixed with black speckles (sorry for the descrpition sounds like art class but all I could think of) but there was no metallic particles in the screen.

What I did see that I wasn't sure if it was normal was the clutch packs that are visible from underneath next to the valve body had about 1/4" of play back/forth in all the discs when I moved them with my finger. Is this normal?

The TV valve was all in tack, nothing out of the ordinary. It there anything else I should look for before removing valve body?

I just don't want to start taking things apart for no reason. Thanks

paul

 

[TexasT]

Sounds like a lot of play on the low/rev set. I wonder how much there is on the direct?

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[PaulRV6]

Any other comments regarding what it could be before just yanking it out would be appreciated. Thanks

paul

 

[TexasT]

Good possibility that the valve body could be the culprit as that is what was changed. You might try changing it back to see. Might be a pinched or torn gasket. You won't know for sure until you take it apart.

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