The upper belt-tensioner shock bolt is a blind hole into the head approx. .875"/22mm deep, not a through-hole. I removed the bolt on an engine (603 w/ later head) today to check.

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Gone to the dark side

- Jeff

It looks as I misread the problem. I apologize.

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Peach Parts W124.128 User Group.

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when I first read this post, I thought the same thing. "wow, havent seen one of those in while..."

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Thanks everyone for your replies.

A special thanks to babymog for measuring the depth of the bolt hole, which is really useful information!

I figured out how to drill the bolt out and re-tap the hole without having to remove the radiator.

I ended up buying a Ryobi flexible drill extension that can bend up to 90 degrees. The extension accepts hex quarter inch drive bits; so, I also bought a drill bit with the quarter inch hex drive from Home Depot. I bought the tap from a local machine shop.

In order to get access to the snapped bolt to drill it out, all I had to do was to remove the clips that hold on the fan shroud to the radiator. I popped the shroud up enough to slip the flexible drill extension under it. I held the drill bit end in one hand and the drill in the other. I was able to drill it out fairly easily; but was a little off center because I first drilled it in order to use a bolt extractor because I could not find the correct tap at first and thought I would be able to remove it with the bolt extractor. I was wrong.

Anyways, I bumped up to the correct drill bit for the tap and drilled in very carefully because I did not know how thick the wall of the head is and did not want to go all the way through.

After drilling with the bit so far, I ground the tip of the drill bit off to make a flat bit. Then, I drilled out the taper left in the hole from the standard bit shape.

Next, I tapped the hole starting with a pipe tap. Because, I could not find a bottoming tap, I ground the pipe tap down to make a bottoming tap. I finished tapping the hole with the bottoming tap.

I put a new bolt in with a little blue thread locker because I felt my threads might be a little shallow due to a little bit of wobble that is inherent when using a flexible drill extension that is really only meant for driving fasteners, not drilling

Anyways, the bolt went it in and snugged up nicely and my tensioner is working properly again. Hopefully, my drill and tap job will hold up. If not, I guess I could always heli-coil it.

Thanks again everyone for your replies!

Thank you. I could just as easily have been in error. My pictures were taken as part of a head replacement project and didn't show the upper bolt hole clearly.

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"Buster" in the '95

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