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  • 1965 - 1973 Classic Mustangs -General/Talk-
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trans issues

  • Thread starter Thread starter woodsnake
  • Start date Start date Feb 18, 2009

woodsnake

15 Year Member
Jan 16, 2007
1,352
15
69
Hicksville, NY
Feb 18, 2009
#1
  • Feb 18, 2009
  • #1
Well, to bring every one up to date, earlier this summer I swapped in an 83 5.0 and my rebuilt C4 from a 67 merc comet.
I had the car running earlier, and it seems to make plenty of power. It will shift into reverse, but when I try to put it in forward, nothing happens.

So, out comes the trans, back to the experienced builder, with the above story. He goes thru it and says the only think he see's wrong is forward apply clutch "O" ring is old and worn. Nothing else inside is wrong.
New "O" ring, back in car, car running tonight. Run the car to normal operating temperature, no weird noises, other than it has sat for so long with out running.
Same story, goes into reverse, but no forward. Now,
Before I go buy a new valve body for it, do you think a totally wrong band adjustment could cause all of this headache??
 
S

stonecoldtx

Member
Aug 4, 2007
214
2
18
Dallas, TX
Feb 18, 2009
#2
  • Feb 18, 2009
  • #2
It sounds like there's a problem with the forward clutch pack and/or drum.

When you put it into reverse, the transmission uses the high gear clutch pack and the reverse band

When you put the trans into drive, however, it uses the forward clutch pack only

It's possible you have a problem with the valve body, but it really sounds like a problem with the forward clutch
 

woodsnake

15 Year Member
Jan 16, 2007
1,352
15
69
Hicksville, NY
Feb 18, 2009
#3
  • Feb 18, 2009
  • #3
It's all new clutches though. I completely rebuilt it, under close supervision.
All "performance" parts, and a shift kit.
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Feb 19, 2009
#4
  • Feb 19, 2009
  • #4
A friend of mine had the wrong sealing rings on the pump and it did the same thing. The high reverse got pressure but none to the forward chutch.
 
S

stonecoldtx

Member
Aug 4, 2007
214
2
18
Dallas, TX
Feb 19, 2009
#5
  • Feb 19, 2009
  • #5
woodsnake said:
It's all new clutches though. I completely rebuilt it, under close supervision.
All "performance" parts, and a shift kit.
Click to expand...


That doesn't mean that there isn't something wrong with the drum . . . or, as was posted by Brian, the sealing rings on the pump--maybe even the sealing rings in the drum itself on the piston.
 
B

brh66cobra

Member
Feb 19, 2009
35
0
6
Feb 19, 2009
#6
  • Feb 19, 2009
  • #6
Did he replace both piston seals or just the inner oring? If you drop the valve body you can air pressure test it thru the holes in the case. This way you can rule out the drum, piston seals and pump rings.
 

woodsnake

15 Year Member
Jan 16, 2007
1,352
15
69
Hicksville, NY
Feb 21, 2009
#7
  • Feb 21, 2009
  • #7
My builder said he air tested the trans. I'm going to try and replace the valve body over the weekend...
If not, the problem will wait until July when I get back......
 

woodsnake

15 Year Member
Jan 16, 2007
1,352
15
69
Hicksville, NY
Feb 22, 2009
#8
  • Feb 22, 2009
  • #8
Success! I changed out the valve body, and it wants to turn the tires with authority while in the air. I still have some timing and carb adjustments on the combo, but this is a big step forward!!
 
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