727 Problem

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J

James Clews

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I have a Australian Valiant 318 with 727 torqueflight and the box is a 1978 model. The car had been sitting for twenty five years so I have taken a full restoration and rebuilt the engine and put new seals and a transco kit in the auto. My brother is the auto tech guy as I have only ever had manuals and this is my first auto. When we fill the auto , start it and select reverse it goes in the first time then no more reverse but forward gears work. We have pulled the valve body out twice but it does the same think everytime. Reverse worked once then no more. Do you have any ideas?
 
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low reverse band snapped? how fast was engine spinning when you engaged reverse. Not a good idea to engage reverse on an unusually high "fast idle", especially if someone has put a kit in the trans and jacked up the line pressure. Or maybe the band strut fell out. Drop the pan and have a look-see.
 
Pull the valve body back off and air check the reverse band servo !! See if the servo moves! Then see if the band moves when you put air to it ! If the servo doesn’t move , pull the servo piston out and see if the piston was just stuck! Or see if the sealing ring or piston is bad ! Make sure the band strut and band are in good shape and adjusted properly !!
 
Is that Ford blue?

I gotta hand it to yall down there, yall have alot of respect for the four door cars! I like them too, but they don't get near the respect here as they do there.
 
Since we can't see what was done, all guesses here. I would take it out and tear it back down. Always easier the second time. They are not as complex as most people think. Hopefully you are using the equivalent of a factory service manual. Take your time and follow the steps. Unless there was a part failure which you will see and need to tear it down anyway to fix, something is in wrong or out of adjustment. Lots of work but you will know for sure and not look back when it is done.
Just because someone is a "Dr." doesn't always mean he can do brain surgery or any other surgery for that matter. Everybody has a specialty. In my shop, normally brake mechanics didn't do tune ups...
 
Maybe the fluid level is just high enough when it's in park to engage reverse the one time, but it would keep on engaging reverse if you went back to park; but never crossed neutral. Are you checking the level in neutral running?
 
I have had a good think about it and as it has sat for 25 years and the new oil that we have put in has already turned black we think that the bands and or clutches are falling apart every time we put it in gear. Maybe they are falling apart because of the long 25 years sitting? Band adjustment is okay and oil level is checked before selecting gears, so will pull out and dismantle to find the issues! Yes rusty this one will just be a cruiser as it has power windows , air ,steer , leather etc and yes I have a Valiant charger(2 door) with 410 and five speed manual that runs low elevens also.
 
Have you drove it? Does it shift into 3rd when driving it? If not my guess would be the inner lip seal in the direct drum is allowing fluid past it. Most kits you buy nowadays have a thicker direct drum lip seal as the factory one was on the small side but, this seal is usually in a seperate bag in the kit. If you were not aware what it was for you could have put the factory size back in it and, with the added line pressure from the shift kit it may be blowing fluid past that seal. That clutch pack is applied during reverse and 3rd gear so, if 3rd gear is also flakey then I would point towards that.
If third gear is fine then check the accumulator piston and seal for the reverse band. You can air test this with the valve body out. The accumulator piston could be cracked or the seal around it could be bad.
Of the oil is that burnt already i would lean towards the direct drum lip seal.
 
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We fixed the problem by putting a standard valve body in and it now works properly. The transgo kit gave a different shift piston so we think that this may be incorrect for my valve body. Down the track we will put the standard shift piston back in the valve body and put that valve body back in to see if this works. Have any of you guys had this issue with a trango kit installed before?
 
Which number? I've had issues with the TF2. The TF3 is supposed to be their"stick shift" manual shift conversion. I have used that, but, didn't do the manual shift part of the kit. Had better results than just the "2" kit.
 
James Clews said:
We fixed the problem by putting a standard valve body in and it now works properly. The transgo kit gave a different shift piston so we think that this may be incorrect for my valve body. Down the track we will put the standard shift piston back in the valve body and put that valve body back in to see if this works. Have any of you guys had this issue with a trango kit installed before?
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I’ve never had that problem. Did u adjust the new manual valve? Kim
 
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