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Discussion Starter #1
So I bought one of those Trick Flow C4 pans with extra capacity and bolted it up with the supplied gasket. Everything looked fine after I had run it for a day. Two days later I look under the car and it's leaking from what looks like every bolt hole, not necessarily the gasket. So I try again by replacing the gasket and snugging the bolts to about 20 ft lbs, the book called for 13-15. I tried running it again and it looked fine until about 2 or 3 days later when it started leaking again! Could it be that the bolts are slowly backing out?

Any ideas? I wanted to drive to work this morning but couldn't because of the leak. Darn it!

ps: I haven't posted in a while and it looks like my free hosting web site will not allow me to link my pics anymore.
 

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It is very possible that the leak is really coming from the dip stick tube. The 'O' ring may be bad. Replace it and see if that cures it. It's pretty doubtfull the pan bolts are backing out.
 

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After I installed my Trick Flow pan, I retorqued the bolts the next day (after 50 miles of driving). They turned maybe a 1/12 of a turn.... It did not/has not leaked a drop.

Are you SURE the leak is from the pan? With it "leaking from what looks like every bolt hole", it sure sounds like a dipstick tube o-ring or cooler line. Also, IIRC, the bolts included lock washers, didn't they???
 

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Discussion Starter #4
Is this even possible with the car just sitting? I didn't think the fluid went up beyond the base of the tube in non operating mode. I'll check later today though.
 

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Discussion Starter #5
Yes, lock washers are on. If I get under there and find that the bolts are backing out, what else can I do to make them stay? Loctite?
 

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Maybe thats the "Trick" in Trick Flow! Sounds like they make better heads than pans, I sugest you try another gasket. Did it come with one of those cheapo paper ones? Maybe a nice cork one will seal better. I do not think it is possible for the bolts to back out if the car is just sitting. Good luck.
 

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Get under there and find out. I doubt they are backing out. The gasket could be relaxing a little bit though. I wouldn't recommend loctite in this situation.

The torque convertor can drain back into the case as the car sits, raising the fluid level, and causing the o-ring to leak. The dipstick tube o-ring is one of the most common leak points in a C4.
 

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I had the same problem and it was the dip stick O-Ring
 

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I just recently had to battle with the same problem, but I was reusing a stock pan, and I would find it hard to believe that your new pan is warped already. Anyway, on my stock pan, the areas around the bolt holes were slightly raised up from years of tightening I assume, so I had to hammer them back down until they were close to flat. I then picked up a new gasket (rubberized) and some soft set permatex. Made sure to get the permatex around the bolt holes. Then I bolted the pan back up at about 15 ft/lbs. You need to make sure that the surfaces are clean when you put new gaskets in. Otherwise, if they are not flat, it makes it that much harder. Since I used an additional sealant, I also let the pan set up for about 30-40 min before I attempted to pour tranny fluid in, since I have found that transmission fluid will eat away at just about everything. I haven't seen a drop of fluid since, and it has been about a week of driving now.

Good luck.

Dave
 

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Couple things...

One does not torque a 5/16" NC grade 5 or less bolt to 15-20 lb-ft, especially into aluminum....
As a comparison, a grade 8+ 5/16" 289 connecting rod bolt gets torque between 17-21 lb-ft on average...

Modest pull on 1/4" drive ratchet should be all that's necessary...I've had trannies go for a decade or more that way, or in the case of the race car, multiple seasons...at the most, road dust collects on a light film of ATF over the years.

Clean surfaces, a flat pan gasket rail and a good old-fashioned cork gasket are all I use...I secure the gasket to the pan with some Permatex #2 to keep is from sliding around and that's it...I don't even recall using anything but the OEM captured washer bolts, with that modest pull on 1/4" ratchet *G*.

If you want to use Loctite, the bolts and holes need to be cleaned of any oil and the blue variety (or any Loctite recommended for removable fasteners in aluminum) can be used sparingly, as in a little dot on the bolt threads. Tighten as mentioned before...

Have fun! Oh, and don't forget to check other places for leaks...things have a babit of running down to and along the pan rail and giving the illusion of a bad pan/gasket...
 

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I agree.......... I have seen this situation before as well. Along with the dip stick o'ring, I have found the front pump seal was leaking. Not to be confused with the torque converter seal. Just another .02 in the pot.
 

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Transmission bolts are spec'ed at "inch pound" torque settings. I have the same trouble with my FMX on my 70 Mach 1. I spent an entire afternoon replacing the shift linkage seal and O ring to stop a leak. It still drips. BTW...I have also torqued my pan bolts and after running the car around for a few days, rechecked the bolts and found they had backed out.
Beats me. I do know when it will stop leaking. When all the fluid seeps out!
 
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