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Tranny problems

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xsteamer

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Occasionally, usually after the car has run awhile, I engage reverse and rev and nothing? The same thing happens intermittently when I down shift to second gear, It's like I'm still in third or I rev and no forward motion. Opinions please.
 
Shift forks. Just a WAG.
 
Yep, not a syncronizer...might be a broken fork...can you shift gears without using the clutch while the car is rolling?
 
Haven't tried to shift without clutch. How do I check the forks?
 
Well, there's an inspection panel on the side of the trans - don't know what you can see with trans up in car but when panel is off & trans is on a bench, you can see the forks.
 
Not much room to do anything with the box in the car. Sounds like one of the forks may either be well worn or have come loose from the shaft. Either way it looks like the box needs to be benched and gone thru.
 
Is this an OD transmission? The OD should be out in 1-2-R gears, but in on 3-4. If everything is normal in 3-4 but in 1-2-R its like you have no transmission, that jibes with the OD.


If you have OD I'll expand on why I ask later /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

Edit: Actually, you said in 2nd it acts like its in 3rd which doesn't work toward where I was going...
 
Ok, I'll relate my story then. I'm sure Tony can elaborate on some of the things I'm not all that clear on.

I had very similar problem years ago. I finally realized the transmission was "slipping" (in fact it often acted like there was no gearbox, just like yours) only when the OD was off and when it was warmed up. That meant when I was in 3rd with the OD on, then downshifted to 2nd I had the problem. If I switched the OD off I'd have the problem intermittantly in 3rd and 4th too - but I don't recall that it was ever that bad in 3rd and 4th. The key seemed to be, if I started off cold and never used the OD I'd never have the problem. If I went out for a long ride and used the OD, once everything got hot I'd lose either partially or completely 1, 2, and reverse. 3-4 with OD still worked.

FYI (skip ahead if you know this, thought I'd mention it), the OD has a conical wet-clutch arrangement that slips between "direct drive" and "over-drive". The clutch gets forced in or out when you hit the OD switch on and off. The clutch is still a clutch in both modes, and thus is prone to the same types of problems other clutches can develop - even with the OD off. It can glaze or not engage properly, causing slippage. I think that's one of the reasons a lot of people are absolutely insistent on not using anything but old fashion 20w50 oil in the OD transmissions. Using synthetic or additives that are otherwise ok for the gears aren't ok for the OD's clutch.

I ended up deciding either the clutch in the OD was bad, or it wasn't moving all the way into direct-drive.

As a hopeful quick-fix I bought a case of the most "normal" 20w50 I could find (at the time it was Castrol), drained the transmission oil, replaced the screens, cleaned the magnets and access cover.

That clutch in the OD is operated hydraulically off the same oil thats in the gearbox. The oil is diverted to the OD system when a solenoid moves a plunger and a small ball (looks like a silver BB) into a valve-seat. I thought maybe the solenoid, the plunger, or the ball were binding and not completely releasing the oil flow (figuring as it heated up something in that assembly was binding) - so I pulled all that out of the OD too. I cleaned the plunger, replaced its O-rings, and replaced the "ball". I pre-oiled everything with fresh 20W50 as I reassembled.

After tightening everything up I topped off with my 20W50 and everything has been 100% perfect since.
 
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