Hey guys, After my th350 suffering from leaks and various other troubles I decided to have a go rebuilding it. I'll tell you first of the parts I've replaced: All bushings (gauged by the old ones positions from how they came out not sure if this was correct or not, im not a pro and only using what tools I have available as there isn't anyone local in the uk area to do the rebuild) All clutches and steels All lip seals, square cut seals, d shape seals and o rings (all lip seales chased into place) All oil pump sealing rings, i will tell you though i did have trouble with these sealing, though the air testing "seemed" to be OK. All gaskets All check balls (double checked to be in right place after first road test) All governor and oil pump screen filters. (also double checked to be in right place when removing the valve body) The Transmission was thoroughly washed out and spotless inside. The only trouble I had was getting the oil pump to slide on at the end once the direct and forward clutches were in place. Took a hell of a twisting side to side to work it down, once it was in place the input shaft was quite tight to turn. The problem: I have a VERY weak reverse, if I leave the car to stand a day or two I have reverse, weak, and momentarily but it only lasts a short while. Id say till the transmission oil thins out with heat. I have first gear and second gear which engage smoothly, 3rd gear however is non functional, no sign of any up-shift. I'm looking for any pointers for installing the bushings (think i may get a new kit in case the oil pump ones are damaged?). I did notice from a few searches that people were talking about a wider bushing, the one I had in the kit was a stock size (would this help with sealing and such like?) Also are there any depth measurements for the bushings as to how far they should be driven in? I'm new to rebuilding (and probably learning the hard way) but learning along the way so any information is gratefully received. Best regards Stuart

Do you have reverse? Does it engage quickly, with no slippage, or delay?

Its hit and miss, its there from first start up but its very weak takes a fair few revs to actually get the car to move rather than it being into gear and have to hold it with the brake so id say with some slipping, you can feel it engage but there's not the same bite and lurch forward or movement of the engine (or backward in this case)you get when you put it in drive, like it used to have.

As with 3rd it feels like its slipping after 2nd has engaged and its ready to go up the next gear.

Stu

Problem seems to be the direct clutch drum, its goosed!
The whole part where the sprag sits on has come away from the center of the drum leaving a nice hole.

Stu

The piston has also seens better days too, its also cracked and needing a new one.

Stu

If you need a direct drum I can get a good one for $60 and then whatever shipping is to you.

Managed to get a spare drum just a piston I'm needing now, thanks for the offer though, very kind of you
Question, what may have caused the drum and the piston to go bad, maybe i overlooked it when checking parts but it didnt seem it was like that when it all went in.

Stu

not sure what you mean by the piston unless you are talking on the rod end of the shifter inside? maybe a pic I will try to help you out if I can.

The direct drum piston that fits on the inside of the direct drum to push the clutches onto pressure plates, normally has an outer and inner lip seal with a step on the back for the lip seal on the direct drum.

heres a photo of the part:



many thanks

Stu

FirebirdStu,

I too am rebuilding a TH350, and it's all gone together very well, but the front pump was difficult to install and once installed, the input shaft was nearly impossible to turn. How did you rectify this? Was it the direct drum?

Thanks,
Joe

http://www.hotrodders.com/forum/th35...ch-145361.html