Valve Cover Gasket Stud Needs a Heli-Coil
 

Hello there! I'm hoping someone can clarify something for me. I'm replacing the valve cover gasket on my 2004 X5 3.0L. The hole for one of the valve cover to head studs is stripped, which seems to be a common problem, and easily fixed with a heli-coil. I've ordered a replacement stud from Pelican Parts (Part #11-12-1-718-856-M9) which is described as 7/6X29.5mm. Neither the service rep at Pelican nor Napa auto parts could tell me what size heli-coil kit to purchase. For those of you who have done this repair...what size heli-coil kit did you use?

I believe the valve cover stud is threaded M7( x1) on the side that screws into the head and M6 on the top that bolts to the valve cover nuts - hence 7/6 in part description. Please check me on this.

If this is correct, I believe you will need an M7 x1 helicoil kit of an appropriate length - 25mm

Helicoils will probably work fine in this application, but I prefer time-serts over helicoils as I believe they are stronger inserts and better able to handle multiple in/out of the threaded bolt - although hopefully once you get the stud in, it won't need to come out.

Price out both time-sert and helicoil m7 kits. If there is a big $ difference go with the cheaper one.

Thanks for your advice! We ended up using a M7 x 1 Helicoil kit with a 10.5mm long insert. We considered using a Timesert, but since it wasn't a load bearing application and we couldn't find any in stock locally and didn't want to wait for one to be shipped we went with a Helicoil.



I'd definitely recommend using a genuine Helicoil kit for this repair. We first tried using an off brand one and found the grove in the insertion tool wasn't well cut, leading to the tool either stretching or breaking the tang within the first turn or two. The Helicoil insert (with the provided insertion tool) went in flawlessly on the first try.



I'm happy to report that it's been a few days now and there are no signs of leakage from the valve cover gasket, no more oil dripping on the manifold, and the vehicle no longer smells like it's about to catch fire!