New Rebuild No forward gears

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dwire67

dwire67

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Okay so I get my Trans rebuilt for my race car, have all the good parts installed from CRT trans , Billet drum and all. My Trans guy gets it all done and I put in the car, fire it up and only notice one gear change from 2 to 3rd on the lift. In neutral the tires are spinning under power, I triple check the shifter adjustment and it still acts the same way. I put it on the ground back it out of the garage , have reverse only:banghead: no forward gears
So I pull it out and I was off to the trans guy and he has no idea of what is going on with it. Anybody have any idea's??
 
Did yer builder "AIR CHECK" all clutchs & servos? what hard parts were replaced in it? I assume this is a 727 yer worken on here & there a few diffrent input/foward clutch drums. I ran into this same issue About 12yrs ago when i learnen the trade & i swaped in a erlay foward/input drum into a later (non lock up) foward/input & like a dumb a$$ i didnt aircheck it & sure enoph no foward gears. The later ones have 3 seal rings where the erlay have only 2. Huge leak! just my exp.
 
He says he air checked all the clutches & servos and when I dropped it back off that it might be in the Valve body??
Here is the list of all the parts I had put in 727 Ultimate Sprag 1966-up plus a Billet Steel Front Drum727 Heavy Duty Band Strut 2nd gearTrans Blanket Short 2" Pan727 Front Solid Band Red Lining NEW727 Race pump 1971-1978 only727 Rebuild Kit-Race 71 & up727 Rear Roller Support727 Low Reverse Band Red Lining
 
It's possible it's a valve body problem. Like Hipo mentioned there were different designs of the front drum and pump stator and they have to match but since you said reverse works that tells me the front clutch is working as it's one of the components used in reverse. One of the most common problems I see when you have no forward gears is a problem with the rear clutch as it's needed in all forward gears. He possibly rolled the seal over or cut it when installing it. He should have caught it during the air pressure tests though.
 
This couldn't be as simple as not putting the rings on the output shaft for the governor assembly could it?

In any case he should be dropping the VB and air chk it.
That would tell ya where the problem is ASAP.
 
Just asking why would it have forward gears when it was on the lift? Granted netural acted like it was in gear and it only made one gear change from second to 3rd
 
dwire67 said:
Just asking why would it have forward gears when it was on the lift? Granted netural acted like it was in gear and it only made one gear change from second to 3rd
Click to expand...

Because there is a fairly serious misdirection of fluid somewhere.
It could easily drag clutches and drive the wheels when they are off the ground, and fluid going someplace it doesn't belong when in neutral.
Basically what you have is a trans that slips so bad it won't drive the wheels with the cars weight on them.

Could be loose VB bolts, a cut lip seal, broken sealing rings, or half a dozen other things that only an air check or tear down and inspection is going to tell.

If it makes you feel any better, it should be pretty obvious when it's found.
Just don't burn it up messing with it, because it's not something that it's going to suddenly quit doing.
 
Thanks Trail and the rest of you guys, I pulled out of the car on Sunday as soon as I found out it would not move on the ground, I put it 1 , 2 and 3rd and when it did not move I shut it off. I am very lucky to have such a great wife , she came out a helped me push it in the garage!
 
TB nailed it, clutch drag by itself is usually enough to make the wheels spin while up in the air.

Good to hear you have a great wife. Mine helps me with my car too. Can't beat it
 
Does that billet input drum say what years of 727 it works with? if he just air checked it once built and assembled in the case it will sound kinda funny but may thought it was ok. I always check them both on the pump on the bench before its in the case to see & hear it apply correctly. if sealed correctly it takes very little psi to apply any of them. Hope it is somthen easy man! fyi that 71-up pump should have 3 seal ring if i recall check to see if yer billet input is the same.
 
My transmission guy took the valve body off and checked to see if the bands where applying and they are. The only thing he found was the Park rod was little bent?
I am at a loss on what to do, anybody know a shop that has Transmission Dyno?
 
Did he also check the clutches to see if they are applying? Neither of the bands do anything to make it take off so their the least important with your problem. How in the world did the park rod get bent? That thing is solid rod and very hard to bend. Me thinks you need to find a different transmission man that knows what he's doing.
 
Not sure how the rod got bent, I have been talking with John Cope of CRT transmissions and he is a outstanding guy! He might get my trans if it not fixed soon
 
Maybe someone can post the pic with the locations to air check the trans. Once you remove the valve body there's a row of holes in the case that feed the clutches, etc. You could check those as mentioned above to see if you narrow down where the internal leak is.
 
80fbody said:
Maybe someone can post the pic with the locations to air check the trans. Once you remove the valve body there's a row of holes in the case that feed the clutches, etc. You could check those as mentioned above to see if you narrow down where the internal leak is.
Click to expand...

Here it is in PDF. Hopefully it opens correctly. if it doesn't let me know and I'll re-scan it as a picture and repost it
 

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If he has a tranny shop - he should have a set of pressure gages. He should have tested the pressures on the lift to see what had pressure, what the pressure did as rpms rose, and what had nothing at all. Sounds more like a valve body issue - it doesn't have a brake does it?
 
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