Stipped Transmission Pan bolt

If it weren't for bad luck I would have none!

Heading home tonight my AW4 puffed a big cloud of smoke while heading up a hill in the freeway. I thought it would be a good idea to change the fluid and filter; I had never done it since I got the XJ 70k miles ago. While pulling off the pan bolts, I turned one of the bolts two clicks and it fell out... I didn't think too much of it as I was trying to wrestle the dipstick column and all. After cleaning everything and installing the new filter I found that hole was stripped. The bolt that could not be put in was one towards the front, next to the bell housing. To make it worse it's the bolt hole nearest the corner on the driver’s side. I went ahead and filled the pan and drove it around. No fluid is leaking. I think I'll pull the pan again, drill and tap the hole, or should I just keep and eye on it. I am not qualified to drill and tap a bolt that goes up into my transmissions housing. What are your opinions?

In the short term...do nothing but keep an eye on it. Trans fluid is very volatile so if it starts leaking bad, stop driving, hot oil on the convertor will ignite.

Long term, DO NOT DRILL A HOLE AND TAP IT. Two reasons, 1st: you admitted a lack of confidence, I'm sure you can do it with a little verbal assistance and encouragement but get a bud over to help just for the peace of mind factor. 2nd: drilling to a larger size will also require drilling the pan to a larger size and also one odd size bolt.

Long Term Better: Install a helicoil for the correct size bolt. The kit comes with the correct size drill and tap (yeah you will have to drill and tap), but it will be the correct size.

Long Term Best: When I worked on transit buses we would strip the pan bolts all the time & this is what we used on the $25K transmissions saving the case...Keene-Serts. Unlike the spring wound Helicoil, the Keene-Sert is a steel sleeve. It also requires a drill and tap but it is a lot stroger than a helicoil and will not come out of the case which helicoils will sometimes do. I believe they are easier to install than a helicoil. The outside of the sleeve is threaded into the trans case and the ID is threaed to the OEM bolt size. The sleeve has four pins that need to be 'staked' with a special punch (provided in the kit) this staking is what prevents backing out when removing the bolt.

Problem is Keene-serts are hard to find at a small local place, we ordered ours from Patterson Parts in SF who bought them from a place in LA. (we couldn't order direct)

Good Luck,
Tom

Tom,

Your knowledge has helped. I think I 'll call the local tranny shop here in Castle Rock and ask them what they do in the situation. I personally don't care about having a different sized bolt. I was planning on putting in a temp gauge in the next few weeks, maybe I'll move that up to tomorrow. That will help me keep an eye on any temp issues realated to leaking fluid.

****es me off that the previous owner or owner's mechanic just let it go. argh

John,

There is also a product out there for "welding" aluminum that is a lot like brazing. You use a propane or map torch to heat the aluminum until it melts the rod. Then use the rod to fill the area you want to repair. In your case you would heat it up and line the hole with the filler. Then drill and tap to the original size. I used the stuff to repair aluminum AC lines that I had to cut. It really is cool stuff and is fairly easy to work with. Here is the stuff I bought,

http://www.jcwhitney.com/autoparts/ProductDisplay/c-10101/s-10101/p-163323/mediaCode-ZX/appId-384969

Just another option I thought you may be interested in.

B-loose

While fixing the leaky trans pan gasket on my "new-to-me" XJ, I found the exact same hole you describe w/ a Broken bolt in it. Drilled it out and then the dang EZ out broke off in it. @!*&%#!! Didn't want to mess w/ trying to drill out a hardened EZ out, so I just drilled and tapped a hole near the broken bolt and added a new screw to the pan. Working fine so far. (knock on wood)

I ended up fixing it with a 7mm tap. The hole was already 6mm so I took a 6mm drill bit and lightly cleaned out the hole. I then used a 7mm tap to tap a new hole and whadoya know, all done. Thanks for everyone's help!