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Hi everyone,

For some reason my trans seems to always leak. At the CV (or would it be called a ball and socket?) boot the trans leaks. It has had new boots on it, tried using sealer, and no luck. That will last for a couple of races then start to leak again. Do the boots need to be drained to avoid filling up and leaking, or is there something else going on here.

I also replaced the gaskets that hold the shaft onto the trans case, and axle seals, no leaks there!!

thanks
Jim

Often the side plate that holds the axle in place gets bent from a hard landing. Either pull the axle off and check the bolt holes for bowing and straighten or rotate the plate 180 degrees and put the bottom on the top and see if it stops. Make sure the intersection (the screw part) of the hose clamp is on the split in the boot. It's the only way the clamp will totally close the boot seam.

Jim,

Make sure you are not filling your transaxle case to the VW recommended level. VW says to fill to the bottom of the inspection/filler hole. Actually you ONLY want it to about 1 inch below that level. In racing you will get more than enough lubrication and the lower level and won't fill the axles tubes as much. We pull 1.5 G's. The Beetle never saw that unless they rolled over.

Jim

Jim,

A couple ideas/suggestions:

1. I concur with the advice so far given.
2. Have you tried to rinse down the side cover and boot areas before a session and then locating the source of the leak after the session. If you can isolate it to the exact source, it will be easier to determine the proper fix. If replacing the boots fixes it for a while, it may just be the boots. However, it might be something else that gradually gets the boots wet.
3. If you go to the effort of removing the axle tubes and checking everything out, make sure the sheet metal axle tube flanges are straight and flat where they seat to gaskets on the sidecovers. As Brian described, the plates get distorted if the axle travels too far in an accident or major "off". I still have two like that on my car from last years Runoffs . Also check that the bell of the axle tube is square to the tube itself. They bend too.
4. When putting on the boots, I have had pretty good luck with blue or black Permatex silicone under the boot at the clamps and along the seam. The boot material must be free of trans oil at these locations or you're wasting your time applying sealant. Also, I was taught to put the seam at a 45 degree angle. The top and bottom of the boot need to flex the most and the seam doesn't stretch. Putting the seam horizontal risks slow leakage at the seam. Thus the 45 degree compromise. I also try to compress the boot slightly towards the trans as the silicone cures. I believe this gives the boots a bit more ability to comply as the axle moves up and down.
5. Years ago, after a few races, I found small holes in my axle boots. It turned out they were made by pinning the boot between the axle tube and frame when I jacked up just one front wheel to perform my standard, one side and then the other, brake adjust/valve adjust. Another earned in the school of hard knocks.

Hope this helps,

I might add that there are plates available that bolt onto the outside of the axle flange. I have used these with great success as I have tended to go off track once in awhile & bent an axle boot flange! You do need longer studs with these plates. There are two style one is a complete plate the other is a split plate where you don't have to remove the axle tube to install.

Dave


http://www.ddcracing.com

You may find it impossible to seal the two piece sheet metal axle tube flanges on early transmissions. If the tranny was not professionally built you may have a bunch of mismatched parts, IE: o-ring side covers on non o-ring case.

Dave

Thanks for the advice. I will have to take a closer look.

I have been overfilling it. I add fluid until it starts to leak out the top. Just how I have done most auto Trans in street cars. I'll try to drain out a little of that fluid. Using the Redline light weight stuff. I'll also try to reattack/seal/orent the boots best I can.

Thanks everyone, I'll let you know how it works out with this, before I go pulling off that plate again.

Jim

Does your trans have a breather hose??? I've heard that with heavy loading of the boots along racing speeds a trans will build a lot of internal pressure and be prone to leaking without a breather hose. Also check that the hose is free from any kinks.

Actually, I don't believe I have a breather. (unless its burried and hidden). Where is the best place to install/look for one?

Thanks
Jim

Look for a small hole at the top of the tail cover casting above the shift linkage. If you have a fitting there that is for your vent line. If not that is where you would put one. A 1/16 NPT barbed fitting works good. You will have to take the cover off and drill and tap the hole. Be careful as the casting is kind of fragile. Make sure that you don't tap too deep so the fitting won't go in too far and block the passageway that leads to the hole. Then you can run a line to a catch can, I use a 3/8 plastic line. As long as you stay away from your exhaust heat should'nt be an issue.

Dave

I took a few pic's for you. My short box has a hole drilled and tapped on top of the transaxle. My long box has the typical vee method of venting the transaxle case by drilling and tapping a hole in the back of the case. Try and run the shortest length of hose to a catch can, use two cans if you have to.


Long box
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Short Box
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I have been overfilling it. I add fluid until it starts to leak out the top. Just how I have done most auto Trans in street cars. I'll try to drain out a little of that fluid. Using the Redline light weight stuff. I'll also try to reattack/seal/orent the boots best I can.

YIKES! Don't drain a little, drain a lot. Look on the right side of the box. Pull out the plug on the side wall and let the box drain from there. You will still have too much, but it'll be a ton better than a filled box. Try siphoning some more, or jack up the left side of the car.
When I stick my pinky in that side hole, up to the second knuckle, I'll point the tip of my pinky down. If the fluid level goes up half of my fingernail, that's good. That makes it about an inch below the hole.

Thanks for the pics, and info, there is currently no breather! Looks like I have a little work to do.

To the top I ment to the top of that side fill plug, not the entire case (I'm not the crazy!). Still to high, I'll drain some out.

So I drill and tap the that cover when its still attached to the trans...then I am good to go. (Hahah just kidding) Just won a milling machine on ebay, sounds like I have an excuse to hurry up and hook it up!

Thanks
Jim