Need Help with Trans Pump Seal

[87chrisss]

Before i install my trans i want to change the oil pan gasket and the front pump seal 2 people have told me i need to take oil pan off then take out the tcc solenoid then i can take out the front pump to change the big O ring seal..can someone help me out i want to do this tomorrow..

ive only changed filter and the tcc solenoids on the 200's not much more i just want to make sure this damn tranny doesnt leak once i put it on so i rather just change it out..step by step would be great..

 

[bison]

You dont need to remove the pump. The seal isnt usually a problem though. It will usually blow the entire seal out of the bore before it starts to leak. Just use a chisel and crush one side of the seal toward the center and pop it right out. I use anaerobic sealant on the od of the metal flange of the new seal. Permatex #51813.

 

[87chrisss]

ive changed those, But the one im worried about is the "stator pump" does that take a seal or gasket?...its kinda wet around there not sure if its from just being stored or from the bad oil pan gasket...

 

[SSedan64]

Those aren't common leak areas.
There's a 'pump to case' Gasket and a pump O-ring, fits in groove of front pump Body, Pic >> https://www.wittrans.com/Schematic.aspx?Transmission=200-4R&Schematic=2
Pump bolts also have gaskets.

 

[bison]

ive changed those, But the one im worried about is the "stator pump" does that take a seal or gasket?...its kinda wet around there not sure if its from just being stored or from the bad oil pan gasket...

View attachment 156895

Thr stator isnin the converter and is surrounded by fluid. It's not a leak point. There is a pump assembly to case gasket, square cut o ring, and sealing washers for the pump to case bolts. I've seen many leaky tv grommets that the owners thought were pan leaks.

 

[87chrisss]

ok...what i'll do is i'll change the oil pan gasket/filter take a vid inside trans and post it up here and you guys can let me know if everything is alright thanks,

 

[bison]

A video won't help us diagnose a leak. I'd just reaseal the entire thing. I'd also go through the trouble of opening up the oil return passages and replacing the front bushing and checking the flywheel for runout to be sure I'm not going to be leaking again.

 

[SSedan64]

Change all the External Seals while you're at it >> http://www.ebay.com/itm/GM-Chevy-20...pt=Motors_Car_Truck_Parts_Accessories&vxp=mtr
may also have a Pump Bushing available, Teflon coated.

As 'Bison' said:
Enlarging Pump drain back hole, 1/4" Bit >> http://www.crankshaftcoalition.com/..._and_tricks#Drain_back_hole_behind_front_seal

Staking the Pump Bushing >> http://www.crankshaftcoalition.com/wiki/T-700r4_through_4L70E_tips_and_tricks#Stake_the_pump_bushing
If your Pump Body is a 690 casting it may already have the machined step which prevents the Bushing from moving forward, cutting & blowing out the Seal.

 

[bison]

If it's the late casting you don't need to stake it. It's got a step for the bushing so it can't walk out. I always use a bearing retaining loc tite on that bushing also.