Rebuilding a TH2004R. Is it possible....?
- Thread starter McHaggis
- Start date
So if the pump body doesn't run true with the stator support the face should be machined so it is true. If you do that I guess you'll need to machine the back of the body that mates to the case too.
Is a typical lathe cut smooth/fine enough to promote a good seal with the pump body?
How much of a cut is too much?
Is a typical lathe cut smooth/fine enough to promote a good seal with the pump body?
How much of a cut is too much?
Yes, if it's not true front & rear of the "Cover" need to be cut. The Front half of Pump is called the "Body".
Yes, smooth cut is fine, a gasket is used between the 2 Pump halfs.
I'm not sure how much is too much but, it should only take a small cut to true them.
Well that shows you how much I know! I gotta get this thing apart as soon as the TH400's together and see what's in there! I didn't realise there was a gasket between the halves. I kinda assumed it would be like the TH400's etc.
What areas of a used pump should be examined closely to make sure that it's OK to rebuild? Or put another way, what are the usual problem areas that cause these pumps to fail?
I'm half awake/asleep
.:redface: There's no Gasket between the 2 halfs. It goes between the rear cover & Case like you thought. :smile:Main areas wear in the Pocket in front Body, wear in Valve bores in rear Cover, Bushing in front Body, replace Stator tube with one with Hardened splines.
pump
I believe SSedan misspoke on the gasket. There is no gasket between pump halves. There is a gasket between back of pump and trans case and an o-ring that goes in a groove outside of pump to seal side of pump to case. Also sealing washers underneath head of bolts that secure pump to case. Scored rotor pocket is the main thing to look for. Minor scratches will work (IMO) or have for me but deep scratches will leave a path for compressed oil to escape loosing valuable pressure. I watched Lonnie lap the 2 pump halves once to make sure they seal (flat). IMO, a 10 vane kit (rotor and vanes) the correct slide spring or springs (opinions vary but the stock dual BRF springs works well), a good pressure regulator stackup (.500 boost--.300 reverse boost and a TCI or Art Carr spring), hardened rings and hardened stator tube should get you well on your way to a 250 psi pump. There is a bushing in the pump body that the convertor snout run through that will probably need to be changed out. A gasket kit will have the necessary small parts. While I'm thinking about it there are some scarf cut sealing rings that I prefer to change to solid ring. 3 on the input shaft--2 on the forward drum shaft and 3 on the center support (2 if dual feeding).
I believe SSedan misspoke on the gasket. There is no gasket between pump halves. There is a gasket between back of pump and trans case and an o-ring that goes in a groove outside of pump to seal side of pump to case. Also sealing washers underneath head of bolts that secure pump to case. Scored rotor pocket is the main thing to look for. Minor scratches will work (IMO) or have for me but deep scratches will leave a path for compressed oil to escape loosing valuable pressure. I watched Lonnie lap the 2 pump halves once to make sure they seal (flat). IMO, a 10 vane kit (rotor and vanes) the correct slide spring or springs (opinions vary but the stock dual BRF springs works well), a good pressure regulator stackup (.500 boost--.300 reverse boost and a TCI or Art Carr spring), hardened rings and hardened stator tube should get you well on your way to a 250 psi pump. There is a bushing in the pump body that the convertor snout run through that will probably need to be changed out. A gasket kit will have the necessary small parts. While I'm thinking about it there are some scarf cut sealing rings that I prefer to change to solid ring. 3 on the input shaft--2 on the forward drum shaft and 3 on the center support (2 if dual feeding).
I'm half awake/asleep
Main areas wear in the Pocket in front Body, wear in Valve bores in rear Cover, Bushing in front Body, replace Stator tube with one with Hardened splines.
LOL. It was late here too so no wonder you were half asleep! :biggrin:
CK Chris's VBody Recalibration kit will have the parts for good Pump Line & TV pressure. Also look at Posts #25 by Jakeshoe & Post #33 by Lot in this thread.
Pressure Regulator Spring
TV/ThrottleValve Boost Valve
Low/Reverse Boost Valve
Pump clearance must be correct for these to work properly.
Good Parts Info here>> Sonnax Transmission, Torque Converter, Performance, Driveline Parts :: High Performance Transmission :: General Motors :: 200-4R click on the Part#'s, Summary & Instruction links for what these parts do/fix and where they're located etc..
Pressure Regulator Spring
TV/ThrottleValve Boost Valve
Low/Reverse Boost Valve
Pump clearance must be correct for these to work properly.
Good Parts Info here>> Sonnax Transmission, Torque Converter, Performance, Driveline Parts :: High Performance Transmission :: General Motors :: 200-4R click on the Part#'s, Summary & Instruction links for what these parts do/fix and where they're located etc..
Any 10 vane kit? The motor revs to 6700rpm and I've seen some called High Rev Kits.
I guess going with a .300 low/rev valve as Lot recommends would complete this bit nicely?
Thanks! I'm getting a better understanding of what goes where etc. A big help! Cheers :biggrin:
One more pump item that crops up quite a bit is the pump to TC bushing.
I understand these can walk forward and cause issues. An overly worn one will allow too much oil to by-pass and this can push the front seal out. Pressing the bush in with loctite and drilling the oil return hole helps but is this all that's needed?
I've read somewhere (yep DH, I read too much LOL!:tongue that some of you guys stake this bushing into the pump housing? I've also seen a thing called a seal retainer but I can't see how this would help much if there's so much oil pressure present that it can move the seal.
I understand these can walk forward and cause issues. An overly worn one will allow too much oil to by-pass and this can push the front seal out. Pressing the bush in with loctite and drilling the oil return hole helps but is this all that's needed?
I've read somewhere (yep DH, I read too much LOL!:tongue
that some of you guys stake this bushing into the pump housing? I've also seen a thing called a seal retainer but I can't see how this would help much if there's so much oil pressure present that it can move the seal.
turbo nasty
Turbo Dojo / MNTR
- Joined
- Jul 19, 2001
Trans go High rev kit comes with spring and rings and good instructions.
Go with GM vanes, rotor, slide and retainer IMO.
But your pump parts in the donor/core could be just fine and just add the rings and spring and other mods.
Yes stake the bushing
If the pump is done right and u use some red loctite on the seal on it should be good.
There is no downside to using that seal retainer tho. It has 3 or 4 fingers that grab the snout of the pump and it straddles the seal 360
Go with GM vanes, rotor, slide and retainer IMO.
But your pump parts in the donor/core could be just fine and just add the rings and spring and other mods.
Yes stake the bushing
If the pump is done right and u use some red loctite on the seal on it should be good.
There is no downside to using that seal retainer tho. It has 3 or 4 fingers that grab the snout of the pump and it straddles the seal 360
This shows some Info on what can happen if the bushing moves forward. There's a Pic of the Seal retainer which does help.
http://www.turbobuick.com/forums/transmission-talk/283603-tranny-went-kaboom.html
I know there's a thread that shows where/how to stake the bushing but, I can't find it now.
http://www.turbobuick.com/forums/transmission-talk/283603-tranny-went-kaboom.html
I know there's a thread that shows where/how to stake the bushing but, I can't find it now.
