Author Topic: Leak? (Read 1373 times)

RustyRed · « **on:** November, 02, 2009, 08:34:15 PM »

While we had the motor pulled and things apart I had a guy I know do some tranny work on my car.

I haven't driven it much since starting the whole process of removing the engine, cleaning the bay up, etc.

I drove it yesterday and went maybe half a mile down the road before I realized like a dumb butt we had removed the vacuum line and forgot to reinstall it.

I don't think it was leaking before yesterday. This evening I had the front of the car up on stands and I reinstalled the vacuum line really fast. But while I was under there I noticed a small puddle of tranny fluid on the floor.

Could simply driving a short way with the vacuum line off cause this or should I be thinking something more along the lines of a bad pan seal / gasket?

daveSanborn · « **Reply #1 on:** November, 02, 2009, 08:57:40 PM »

Quote

Could simply driving a short way with the vacuum line off cause this

If so, it would be the first time I ever heard of this happening.

blue65coupe · « **Reply #2 on:** November, 03, 2009, 05:45:25 AM »

Check all the pan bolts. When reinstalling the pan, the bolt holes need to be tapped back flush. What happens a lot of times is the bolt holes get pressed in and if not tapped back out they will not get a good seal with the gasket. Clean everything off real good and take it for a short drive. Bring it back and inspect everything. Put the car on stands so you can get under there and see what's going on.

RustyRed · « **Reply #3 on:** November, 03, 2009, 10:53:30 AM »

I went home at lunch to have a look at something. I cleaned up my small puddle last night and today it was a fairly decent sized puddle.

Thinking my pan gasket is the most likely culprit but is there anything else that I should check?

blue65coupe · « **Reply #4 on:** November, 03, 2009, 11:05:39 AM »

The only thing I can recommend is trying to find where it's coming from. If you had more from the car sitting it could obviously be from the gasket. It shouldn't be too hard to tell.

cmayna · « **Reply #5 on:** November, 03, 2009, 11:10:38 AM »

I agree. Get under there, clean everything up and what in an hour+ go back under with your light.

What part of the tranny is the puddle underneath? Should be pretty easy to find the problem. Now fixing it........well that might be a different story.

RustyRed · « **Reply #6 on:** November, 03, 2009, 11:34:58 AM »

Last evening the puddle seemed to be under the front driver's side of the pan...that seemed to me to rule out cooling lines, dip stick, etc since they are on the passenger's side.

I am very very far from the transmission guru but my guess is that whatever is leaking is on the drivers side or guess it could be towards the top and running down the side.

Fast68back · « **Reply #7 on:** November, 03, 2009, 12:52:11 PM »

Check the shaft where the gear selector comes out the side of the tranny. Also, have you checked the fluid level with the trans "hot" or "cold"?

RustyRed · « **Reply #8 on:** November, 03, 2009, 01:14:07 PM »

I always check it after it has warmed up for about 15 minutes.

RustyRed · « **Reply #9 on:** November, 03, 2009, 01:24:25 PM »

Forgot to mention....here's a snap shot of my decent sized puddle...obviously we aren't talking a few drops here. This puddle is after one night and morning worth of sitting.

70_Fastback · « **Reply #10 on:** November, 03, 2009, 02:24:41 PM »

Check around the speedo gear too. But you should be able to see where the "Drips" are coming from regardless. Get under there with a flashlight and try to locate the hanging drips. Mine leaked around the pan bolts because I over torqued them. That was with the stock steel pan and a rubber gasket.

Since then the Tranny Pan Fairy blessed me with a really nice TrickFlow deep aluminum pan, which can't be warped by over tightening. I used the rubber gasket again and torqued to (I believe) 8 to 10 pounds.

No leaks.

blue65coupe · « **Reply #11 on:** November, 03, 2009, 06:01:31 PM »

What Rick and J said. Mine has a very small leak at the speedo gear and runs down the cable and drips on the headers. It's very small and if it left a puddle, it would be toward the front of the pan and not near the speedo gear. A drip that size is gonna be pretty obvious. Get under the car, find out where it's dripping and follow the trail.

cmayna · « **Reply #12 on:** November, 03, 2009, 07:10:10 PM »

Uh what type of tranny are we chatting about?

Does your oil pan have a drain plug? If you find that it is infact leaking from the oil pan gasket, as Jeremy said earlier, you might consider a Tricflow aluminum pan. Very stout and you cannot warp the flange.

But with a leak as big as we see in the pic, it shouldn't be very difficult to find the leak point.

RustyRed · « **Reply #13 on:** November, 03, 2009, 07:17:44 PM »

tranny is a C4. No idea if it is the original one or not.

When I got home I cleaned up the puddle and then put some news print down...hoping that will help me start to figure out where it is leaking. When the boys go to bed in a bit I plan to jack up the car on stands, get a flashlight and do a little investigating.

cmayna · « **Reply #14 on:** November, 03, 2009, 07:35:17 PM »

Did you wipe down the tranny area that is right above the puddle? With a puddle that big, you should be able to see where it is leaking pretty easily once you have wiped down the tranny.

RustyRed · « **Reply #15 on:** November, 03, 2009, 08:37:13 PM »

I got it up on stands and climbed under there flashlight in hand. Maybe I am weird but I honestly hate jack stands...I always stop and mentally think, ok life insurance is paid up right?, LOL!

At any rate, my money is on the pan gasket.

The pan is dripping from the back and the three (or four?) bolts back there had fluid resting in the center of the bolt head. The gasket back there just looks "wet".

Everything else I checked like the tranny cooling lines, where the kick down linkage hooks up, etc were dry as a bone. Really pretty much everything except the pan was dry as a bone.

It makes sense though. The tranny guy came out and did his thing. Since I was still fighting either the flu or pneumonia at the time my buddy put some of the final pieces back together. When I asked him about it today he said a few of the pan bolts seemed a little loose so he tightened them down some. My guess is they might be over tightened.

The plan....get a new gasket. Take pan off and clean off old gasket. Tap down holes as / if required, gasket sealer the you know what out of the gasket on the pan side, let sit while sealer sets up a little then put the pan back on the car....sound about right?

By the way...should I torque the bolts down to a particular spec or just get them snug with a regular socket?

70_Fastback · « **Reply #16 on:** November, 04, 2009, 05:45:44 AM »

There is a torque spec. Which I BELIEVE was 8 to 10 foot punds if I remember correctly. Also use thread sealer on the bolts prior to installing as well.

blue65coupe · « **Reply #17 on:** November, 04, 2009, 07:04:37 AM »

Definitely tap the bolt holes back. Get a thin piece of wood that fits between the pan and flange to use as a backstop.

RustyRed · « **Reply #18 on:** November, 04, 2009, 07:08:14 AM »

I just got off the phone with O'Reilly and they can get the gasket here by about 11:30 a.m. to noon today, guess they don't stock them in the store.

But even tomorrow would have been fine with me. I could always spend my time this evening taking the pan off, cleaning it up and tapping down bolt holes then put off reinstall till tomorrow evening.

I asked one person about it and they suggested to just snug up the bolts....I laughed at that one. Over tightening is probably what the problem was in the first place.

blue65coupe · « **Reply #19 on:** November, 04, 2009, 07:16:51 AM »

Have fun. Tapping those holes takes more time than what you're thinking. Keep us posted.

RustyRed · « **Reply #20 on:** November, 04, 2009, 08:00:05 AM »

Quote from: blue65coupe on November, 04, 2009, 07:16:51 AM

Have fun. Tapping those holes takes more time than what you're thinking. Keep us posted.

It's all good...if it takes me the next three evenings then it's not a big deal. Just ready to work out all the bugs and get the sucker back on the road.

My idle also seems a little high so I think there might be some tuning required at some point before I stick a fork in it.

On the plus side of things....my step brother runs a window washing / pressure washing type business. I might have to have him come over soon, my garage floor is a mess between a major tranny leak, undercoating from another project and even some seam sealer being on there. The joys of owning a classic :-)

cmayna · « **Reply #21 on:** November, 04, 2009, 09:21:43 AM »

Here's a little trick for installing tranny and motor pans. Get a bunch of bolts of correct thread and cut the heads off. Carefully with a hacksaw blade, cut a groove on one end that will accommodate
a small flat head screw driver. Space say 4-6 of these bolts into the holes of the tranny. They become guide bolts for you and will hold the pan or gasket in place while you start threading the permanent bolts into place. Once you have enough permanent bolts in place remove the guide bolts and replace them with the rest of the permant bolts.

This concept can be used for installing tranny's, bell housings, Rear end chunks, etc.

I've made a bag full of different size guide bolts.

RustyRed · « **Reply #22 on:** November, 04, 2009, 11:17:05 AM »

Quote from: 70_Fastback on November, 03, 2009, 02:24:41 PM

Since then the Tranny Pan Fairy blessed me with a really nice TrickFlow deep aluminum pan, which can't be warped by over tightening. I used the rubber gasket again and torqued to (I believe) 8 to 10 pounds.

No leaks.

Warning of possible stupid question but to do the TrickFlow pan do you need to change anything other than the pan? Does a stock dip stick work, etc?

On the plus, I went by O'Reilly today to pick up tranny fluid, the gasket, plus some other odds and ends I've been needing and it was customer appreciation day. Nice to get a free burger for lunch along with my $30 worth of items purchased.

cmayna · « **Reply #23 on:** November, 04, 2009, 12:24:20 PM »

Here's the Trickflow pan that Jeremy is using with his c4. All you need is a new gasket and longer bolts since the flange is thick. I use their pan on the AOD in my daughter's coupe.

Another couple benefits of using them is having a drain plug and they hold an extra quart of fluid.