Stripped valve cover holes repair

[amamet]

Need advice on what helicoils to get. I have a 78 G5 with numerous stripped valve cover holes (swear they came to me that way). I'm just getting around to fixing them. I also have a helicoil  backing out of 1 of the manifold bolts along with a stripped hole for the banjo bolt on the valve cover. Any help is appreciated. Of course I'll remove the head to do the work. Or should I get a used set of heads to replace them
Thx
Allen

[blackcat]

Time-serts will fix the problems.

[amamet]

I was under the assumption that timeserts were better for, say, spark plugs than valve cover holes.  Also there are approx 6 stripped holes. Isn't the  timesert quite expensive too?
Allen

[Perazzimx14]

+1 on Time-serts. Heli coils are junk IMHO.

Since you are pulling the heads why not check into a local machine shop and see what they would charge to time-sert all the holes. 

Time-certs are expensive but your heads are worthless if you can't secure the valve cover to it.

[Antietam Classic Cycle]

I've used Heli-Coils extensively over the last several years, never had a single issue. <shrug>

[travelingbyguzzi]

Nothing wrong with helicoils in this application. Also have helicoils in a couple oilpan locations.
Bill Lovelady

[dl.allen]

I use helicoils in all my old Triumph applications.  Heard good things about time serts never tried them.  I use a tiny bit of green Loctite when installing the helicoil, let it dry before inserting bolt and torqueing up.

[Wayne Orwig]

I have used heli-coils for valve covers, oil pans, and such. I usually add a drop of loctite to keep it in place. For that banjo bolt, you must have it perfectly aligned or it won't seal.

[LeRoy]

As a tip for others, and maybe in the case of the original poster, take a look at the valve cover bolts in the installed position. In many cases the bolts used are longer than necessary. This allows the threaded end of the bolts to protrude past the hole in the head (many of the holes are through-holes, not blind holes). The exposed threads corrode. Then, when you remove the bolts, the crusty, corroded threads rip up the aluminum threads in the head and yield just he kind of stripped threads you are experiencing.

Consider two potential solutions:
1: Change over to stainless fasteners, get them in a slightly shorter length and use a never-seize compound on the threads
2: Even if you don't change to stainless fasteners, get new ones of a shorter length and use a never-seize compound on the threads

[Wayne Orwig]

A box of SS 6x1x25 screws that will do the oil pan and valve covers is less then $10 from McMaster Carr.
I know, there are reasons not to use SS in aluminum. I don't care, a rusted corroded steel bolt does more damage.

[pete mcgee]

Stainless steel is fine IF you use an anti sieze with it to stop corrosion and galling.
Steel and alloy should also have an anti sieze between them.
Buy some anti sieze and apply when ever you remove a fastener.
Helicoils work fine in the valve cover and oil pan fasteners, I would use the keyinsets after the point where the helicoils will not fit.

[jcctx]

may be little "rubish" but in a low stress app like this the next size self tapping screw of your choice would seem to be the shortest time/cost solution???

[rodekyll]

I sometimes 'fix' a stripped 6mm hole with a 1/4" tap and screw.  I don't recommend it on account of it could be construed as a 'hold my beer' repair, but for down&durty it gets the job done.