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C4 Leak

  • Thread starter Thread starter joeythesaint
  • Start date Start date Dec 18, 2005

joeythesaint

New Member
Feb 9, 2003
402
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Seattle
Dec 18, 2005
#1
  • Dec 18, 2005
  • #1
Driving me nuts. I can't get a light far enough up into the tranny tunnel to see, and I can't imagine where this POS is leaking from. It's leaking onto the passenger side header collector, which appears to be about even with the midline of the PS front wheel. Looking at a picture of the C4 tranny, it looks like the high-pressure fittings are well back from that point. Any ideas where the leak might be coming from?
 
I

IIxs

New Member
Dec 16, 2004
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0
Dec 19, 2005
#2
  • Dec 19, 2005
  • #2
Don't know if ths is the problem with yours or not but I had 2 of these cars drive me nuts with a pan gasket that wouldn't seal. Ended up going to NAPA and getting a rubber pan gasket instead of the cork type and that sealed them up. Also since you say it's up by the front wheel you might check the rack for leaking fluid.
 

Blue Thunder

15 Year Member
Mar 20, 2004
1,003
55
68
Upstate New York.
Dec 19, 2005
#3
  • Dec 19, 2005
  • #3
The dipstick tube plugs in around there. Are you sure it's ATF and not engine oil leaking down from a valve cover or rear intake seal and running down the bell?
You can test to see if it's a pressure line leak by cleaning the area with brake cleaner, drying it off, and then let the car sit there and idle for awhile. If it leaks, it's probably a pressure line, if it doesnt leak, it's probably not from a pressure line.
 

joeythesaint

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Feb 9, 2003
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Seattle
Dec 19, 2005
#4
  • Dec 19, 2005
  • #4
It's definitely leaking even when the car isn't running. And it seems to leak more when going up a hill or accelerating. And it's either tranny or PS fluid; it's reddish. I'm thinking power steering fluid. I need to get back under there.
 
M

Markysinatra

New Member
Jun 1, 2004
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buffalo ny
Dec 19, 2005
#5
  • Dec 19, 2005
  • #5
one of my II's had the same sorta leak drove me nuts till I found out it was where the tranny dipstick went into the case
 

joeythesaint

New Member
Feb 9, 2003
402
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Seattle
Feb 13, 2006
#6
  • Feb 13, 2006
  • #6
Markysinatra said:
one of my II's had the same sorta leak drove me nuts till I found out it was where the tranny dipstick went into the case
Click to expand...

How did you fix it? I replaced the O-ring when I had the engine & tranny out and it's leaking again. Did I miss something?
 

Blue Thunder

15 Year Member
Mar 20, 2004
1,003
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68
Upstate New York.
Feb 13, 2006
#7
  • Feb 13, 2006
  • #7
I always wipe a fine layer of silicone around the tube and o-ring with my finger before I plug it in.
 

joeythesaint

New Member
Feb 9, 2003
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0
Seattle
Feb 13, 2006
#8
  • Feb 13, 2006
  • #8
Dan, do you know if it's possible to remove/reseat the dipstick tube without pulling the engine/tranny? I really need to reseal it. Maybe drop the driveline, PS pipe, and tranny xmember?

Has anyone tried this with the tranny in the car?
 

Cool Wheels

New Member
Jan 26, 2004
103
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Nelson, BC, Canada
Feb 13, 2006
#9
  • Feb 13, 2006
  • #9
I accidently pulled my dipstick tube out and managed to plug it back in by sense of touch but I'm thinking that wretched moment in time was responsible for the leak I also have now. Sucks when your project car is your daily driver. Can't exactly pull the transmission and have everything fixed for the Monday drive to work.

Have you checked your coolant lines? Try wiping everything as clean as possible and take small testdrives until you can see the source. Do you have to top up the transmission or powersteering fluid at all? Maybe make a small scratch on either dipstick and check it again in a couple weeks.
 

joeythesaint

New Member
Feb 9, 2003
402
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0
Seattle
Feb 13, 2006
#10
  • Feb 13, 2006
  • #10
Cool Wheels said:
Have you checked your coolant lines? Try wiping everything as clean as possible and take small testdrives until you can see the source. Do you have to top up the transmission or powersteering fluid at all? Maybe make a small scratch on either dipstick and check it again in a couple weeks.
Click to expand...

I do have to top up the tranny fluid, about a half quart every month. It leaks when the car is sitting, and it really leaks when I romp on it or go uphill real fast. White smoke everywhere. Which makes me wonder if it's maybe leaking out the breather valve at the top in addition to wherever it's leaking at rest. In which case, I wonder if there's a way I can build a splatter shield to keep the fluid off the pipes. . . . the mods never end. . . .
 

Cool Wheels

New Member
Jan 26, 2004
103
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0
Nelson, BC, Canada
Feb 14, 2006
#11
  • Feb 14, 2006
  • #11
Well if it's smoking maybe it's spraying out onto your exhaust from somewhere
 

Blue Thunder

15 Year Member
Mar 20, 2004
1,003
55
68
Upstate New York.
Feb 21, 2006
#12
  • Feb 21, 2006
  • #12
Are you sure it's not overfull and thus causing the vent to leak? Also, I'm pretty sure you can change the dipstick tube without pulling the motor, though you might need to remove the trans mount and use a jack to lower the motor/trans down in back some to make room at the firewall.
 

joeythesaint

New Member
Feb 9, 2003
402
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0
Seattle
Feb 22, 2006
#13
  • Feb 22, 2006
  • #13
Blue Thunder said:
Are you sure it's not overfull and thus causing the vent to leak? Also, I'm pretty sure you can change the dipstick tube without pulling the motor, though you might need to remove the trans mount and use a jack to lower the motor/trans down in back some to make room at the firewall.
Click to expand...

I wonder -- it had been sitting for a couple of months; would non-use cause the transmission to hesitate until it's "primed" somewhat? (It was sitting at a downward angle, nose up, on a slope.) Perhaps I did overfill it because the transmission wouldn't shift when I first warmed it up, so I added 1/2 qt. Seemed OK on the dipstick, though.
 
S

snakebite_83

Founding Member
Feb 3, 2000
396
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0
garden grove ca.
Feb 22, 2006
#14
  • Feb 22, 2006
  • #14
Try this one on for size. Dont fill it but when you park it, put some cardboard under it so you can get an idea as to where the leak is. If it is your dipstick, you can put it in without moving anything but maybe move your header out of the way. you are supposed to install it from the top to begin with. maybe just put it on stands and try guiding it in from the bottom while a friend sends it down from the top. and make d..n sure the o-ring is in good shape or replaced and rebolt the tube to the trans. its either that or you might have a crack in the tube,it has happened.

P.S. its not slinging it from the pump seal is it?
 
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