D7G keeps blowing torque converter output seal

[02Dmax]

D7G 92V prefix.

I had the torque out of this thing a few months back to replace the rear main seal that was letting engine oil transfer. Ever since then it has been blowing out the seal at the output yoke. I've replaced the seal 3 times and also replaced the yoke. I'm assuming I boogered something up when I had the torque out but not sure what. I didn't dismantle the converter at all. Just pulled it off, cleaned it up, and put it back on. Any ideas?

 

[Nige]

Did you by chance take any TC pressures while you were working on it..?

 

[oldirt]

converter drain pump failed or worn out?

is the the same tractor you r&r'd the final a while back?

 

[02Dmax]

Did you by chance take any TC pressures while you were working on it..?

No, I haven't checked any pressures on it.

 

[Bob/Ont]

Might have a broken cast iron sealing ring near the back of the torque. Need parts pic to tell.
Later Bob

 

[02Dmax]

converter drain pump failed or worn out?

is the the same tractor you r&r'd the final a while back?

Ya, I went through one of the finals about a year ago.

 

[02Dmax]

When it goes out its a severe leak. It's actually blowing the the lip of the seal out of the tin case of the seal.

 

[Nige]

So it's not blowing the complete seal assembly out of the housing..?
Genuine Cat seals or "will fit"..? Just to rule out a possible material issue.

 

[Bob/Ont]

The cast iron rings hold the charge inside the converter. If the rear one breaks a lot of force will be on the back seal.
Later Bob

When it goes out its a severe leak. It's actually blowing the the lip of the seal out of the tin case of the seal.

 

[Nige]

Bob, Are you talking about the 2 metal sealing rings #4 in the diagram below...?

 

[Bob/Ont]

They might be the ones Nige, could you show me a pic of the shaft Please?
Later Bob

 

[Nige]

This is the best I can do for the shaft .......

 

[Old Magnet]

What leaks past those rings is open to the housing.
The diagrams are for D6C but the G is the same.

 

[Bob/Ont]

What is #6 in the last pic you posted Nige? Was looking for a shaft ring but can't see it on OM's pic's. Failing that it might be a plug left in a cooler line forcing the pressure up to inlet relief setting.
Later Bob

 

[Old Magnet]

#6 is a split metal ring. Looks to be retaining ring for bearing race #5

 

[Nige]

#6 is a split metal ring. Looks to be retaining ring for bearing race #5

OM, It is a split metal ring, but it doesn't retain the bearing, in fact it's a split ring rotating shaft seal.
Bob, Here's an illustration of a TC from a D6R that uses the exact same 9M-2008 split steel ring seal that is used in the OP's 92V-prefix D7G.

 

[Old Magnet]

OK, I see it in my D6R parts manual. Called out as a ring-metal seal. Looks like that could be the culprit if damaged.

 

[02Dmax]

So it's not blowing the complete seal assembly out of the housing..?
Genuine Cat seals or "will fit"..? Just to rule out a possible material issue.

Genuine Cat parts. I do believe I put a Cat Classic yoke in it though.

 

[Heavey Metal]

Might as well overhaul the converter

If you need more convincing do the pressure test and a stall spilltest and see how much oil its making.

 

[tctractors]

If the seal is blown don't bother with any pressure test just move on to the next point, strip out the converter as its going to have problems, often the shaft can move out of the converter towards the tran's due to thrust wear eating into the S/Pump drive gear face, this puts 1 of the steel seals outside the location, anyhow its going to need a full strip out.
tctractors

p.s. remove the S/Pump before the cover is pulled.