I've gone and somehow managed to stip out the threads inside the hole on the power steering pump that recieves the bolt that you tighten to keep the belt tight on my 300d. Its a '76, so the pump is near the bottom of the engine and nearly impossible to get to. Some one was telling me that I could probably use a helicoil on it. I have never had any experience with these. Anyone know about these or if that would hold it?

__________________
"spreading a trail of obnoxious where ever we go"
1981 300sd w/ 341,500 miles

http://www.wecrash.com/pics/ddda_banner.gif

choice.

sometimes you can tap it out and use a bigger bolt though. you prob need to remove the rad to get at it and get a straight in shot on installing the coil.

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I have used Helicoils a few times in years past. They come in a kit with directions and must be purchased for the specific thread size you desire.
We used them on U.S Submarines on occassion and they are just about as strong as the original threads (maybe stronger). They should work fine for that application as long as you have enough room to use a tap and the helicoil tool.

Paul
_________
98 E300

Through the years I have repaired many damaged threads, including one today. I much prefer timesert brand thread repair over heli-coils. Once properly installed they do not come out when you remove the bolt years later.

http://www.timesert.com/index.html

__________________
You can get farther with a smile and a gun than you can with just a smile.

1984 300D
1985 300CD
1980 300SD
1993 SL500

yeah, it looks like I'm going to have to tear everything apart to get to that. The hole is in a really hard to get place. Thanks for the info.

__________________
"spreading a trail of obnoxious where ever we go"
1981 300sd w/ 341,500 miles

http://www.wecrash.com/pics/ddda_banner.gif

Tirebiter,

Where do U buy the timesert thread repairers?

P E H

At almost any good machine parts supply stores. They are packaged with a drill bit, tap, shoulder cutter, and insert bit that expands the bottom of the insert itself to keep it from backing out. One kit for each size insert is all that is needed for each size. So one 8mm kit is needed (about $20) to allow you to install any depth 8mm insert. The inserts are sold in packages of several depths in metric and SAE. The inserts are about the same cost as the less efficient heli-coils.

I've helicoiled many, many holes, and have very seldom had a coil come out. It's really not an issue in practice. It helps to apply red loctite to the coil when you insert it, then let it sit for a bit before installing the fastener.

Helicoils are thinner than other inserts, and sometimes you have absolutely no choice.

I used to have a lot of trouble keeping the alternator tight on my Diesel trucks. I ended up drilling the hold back bolt hole all the way through and putting a nut on the back side. To make it easier to hold I tack weld a small rod on the nut so that it doesn't spin. This may not work for you but it is one solution.