Stripped M013 rocker bolts - PeachParts Mercedes-Benz Forum

samiam4 · #1 10-28-2006, 11:16 PM

Guys,

I've got a 86' 300E. Can I expect to R&R valve seals without helicoiling the rocker arm bolts?? Does someone know how deep the blind holes are so I can order full-depth helicoils. I've got a standard tap and was going to buy the bottoming tap-to get full depth.
The coils are available in 1-4 diameters(8mm-24mm) from my local machinist supply company. How many should I expect to need? a few or does one ussually have to helicoil all the rocker holes.

This engine has never been touched and never overheated to the best of my knowledge.

Thanks,

Michael

Gilly · #2 10-29-2006, 12:15 AM

You mean the bolts that hold the rocker brackets down??
Gilly

dkveuro · #3 10-29-2006, 12:43 AM

Have done quiet a few of these rocker/cam pedastal mounting thread repairs.
They pull out a lot it seems...although obviously, I only see the ones that have.

Just buy regular helicoil kit and have at it....installing the coil just sub surface does the job.

Make sure you drill square with the surface and cover everything with cloths and have a magnet on a stick handy.

.

Gilly · #4 10-29-2006, 08:49 AM

I had lots of these apart and never seen one stripped.
Gilly

samiam4 · #5 10-29-2006, 09:34 AM

Thanks Gilly,

I'll assume that it's not going to happen. If it does, I'll just be without a car for a week while the parts come in.
Do you always upgrade valve springs and bolts per MB's recommendations?

Michael

Gilly · #6 10-29-2006, 10:20 AM

Nope, if there's no complaints I'd leave it all alone. Just be careful starting the bolts, I can see where there would be an opportunity to cross-thread the bolts as the brackets might want to tilt a bit, so just start them by hand at first, or a small nut driver or speeder handle, and be gentle.
When removing the brackets, watch out for the small cup-shaped washers on top of the valve stem, then can sort of stick to the hydraulic compensators.
Gilly