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  • 1965 - 1973 Classic Mustangs -General/Talk-
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C4 leak

  • Thread starter Thread starter garrett66
  • Start date Start date Feb 21, 2010

garrett66

New Member
Jul 2, 2009
27
0
1
SE, Colorado
Feb 21, 2010
#1
  • Feb 21, 2010
  • #1
Okay, so the C4 transmission from my '66 has been leaking lately out of the gap in the inspection cover. It was leaking from inside the bellhousing so my first guess was that the front pump seal blew out. I pulled the engine out this weekend to replace the front pump seal but it looked great. The seal was still on square and looked to be in good shape but i could see how the transmission fluid was leaking down the inside of the bellhousing where the front pump seal is.
Well, I went ahead and took out the seal to replace and found a bushing loose around the shaft. I don't know much about transmissions so I don't know specifically what this part is. It was the same diameter as the seal and had a kind of a channel running at a 45 degree angle on the inside. The bushing was bent out of shape but didn't show any unnatural wear. I really dont know what this means. It wasnt leaking out of the seal so the bushing must be to blame?
Should I just replace the bearing or do you guys think there is a bigger problem?

Sorry about having no pictures.
 
C

cobraii351

Founding Member
Jan 10, 2000
1,104
4
39
Altoona, PA
Feb 23, 2010
#2
  • Feb 23, 2010
  • #2
That bushing is the bushing that the converter rides in. Check the outside of the converter nose to see if it is damaged or not. If that bushing is not in place some of the the output pressure of the pump is hitting the back of that seal and most likely force fluid out as a result. You almost have to pull the pump out of the transmission to replace that bushing, which depending on your level of expertise may mean a trip to the transmission shop. When I replace that bushing I usually use a little locktite on the back to help make sure it stays in place.

God Luck,
Tim
 

garrett66

New Member
Jul 2, 2009
27
0
1
SE, Colorado
Feb 23, 2010
#3
  • Feb 23, 2010
  • #3
Thanks Tim,
It's a brand new 2500 stall converter i bought to go with my new 347. It hadn't been in there long enough to show wear.
How difficult of a job might it be? I don't know a damn about the internals of a transmission but I'm not afraid of hard work either.


Thanks,
Garrett
 
C

cobraii351

Founding Member
Jan 10, 2000
1,104
4
39
Altoona, PA
Feb 23, 2010
#4
  • Feb 23, 2010
  • #4
I've sent you an email.

Tim
 

garrett66

New Member
Jul 2, 2009
27
0
1
SE, Colorado
Feb 27, 2010
#5
  • Feb 27, 2010
  • #5
Thanks for the e-mail. It went well I got the bushing back in there fine and am just waiting for the parts store to get the o-ring in and ill put the pump assembly back in.
 
C

cobraii351

Founding Member
Jan 10, 2000
1,104
4
39
Altoona, PA
Feb 28, 2010
#6
  • Feb 28, 2010
  • #6
Excellent! Just be carefull the the little bushing on the end of the support. Sometimes it is a bugger to get to stay as you get everything alse to settle into place. Like I described use a dab of petrolium jelly to hold it. I also usually use a long bolt or two with the heads cut off to hold the pump gasket in place and make aligning the pump easier. Just another simple trick to help. The torque on the pump/bell bolts is 28-40 ft-lbs.

Good Luck!

Tim
 
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