<sigh>...Anyone helicoiled their head?

[slipnfall]

Hi. I'm putting my valve cover back on today and realized I have *three* stripped holes...Two are the front two, near the cams... the third is the middle of three down the center. Then engine is on a stand so I might as well do it now. I'm not worried about drilling/tapping so much as I am metal shavings. Any tips from those who have done this? All three bolts look like they have the same size thread. Think I should do all all three down the middle while i'm at it? It would make sense to, but then again that's just more chances to goof things up...

Also I read that some people only helicoil the valve-cover itself. Do they just install the bolts upside down then?? Seems gheto, but I guess it's safter than drilling into the head if you don't have to. No such luck here. :-)

Oh and this is all after I snapped a bolt off in my block putting the oil filter adaptor back on... luckily a Craftstman easy-out/power extractor saved the day here. I accidently had my torque wrench set 10lbs too high. I hadn't even hit the valve cover screws w/a wrench yet when I noticed they were stripped.

Thanks for any tips/suggestions.-Jamie

[s13sr20chris]

which engine? and which bolts? i have helicoiled many heads. i have done exhaust stud helicoils, rocker shaft helicoils, etc. its not hard and if you have the engine on a stand then the metal will be easy to clean up. minimize the metal issue by dipping drill and tap in wheel bearing grease before hand. the grease catches a lot of the metal and then you periodically clean the tap and drill. also, use some rags.

[navysnail]

also, somthing that ive always done is turn the tap one revolution, then back it out 1/2 turn to "clear it out"

[slipnfall]

Heh, I was just about to post an update when I saw your two replies. The bolts in question were valve cover bolts on the KA24DE. Originally it was only two small bolts, and one of the larger bolts. After looking closer, there were actually four of the smaller holes that were stripped.

Since the post I'v been digging around trying to find a cheap kit. I ended up sucking it up and bought a $35 genuine Helicoil kit from the auto-store. I must say that it went almost too well... scary well... I figured that I could just make my own insertion tool and buy the refills. They seem to be a hard comodity around my area.

So anyways, the kit came with 10 helicoils, and I ended up doing 5. I'm no stranger to tapping threads, I was just a little uneasy about drilling my head that I just got back from the machine shop. I just placed a shop paper towel under the area, and masking taped it into place. I tilted the engine on it's side when drilling the holes, which left me w/virutally no mess to worry with. Used a little engine oil(didn't have any tap oil) on the tap, and ran the tap in/out twice to help pull the shaving out. Vac'd the rest.

After that it was cake, I almost enjoyed doing it(sick, I know). I didn't have any of the high strenth thread locker, so I used the medium strength stuff(blue).

I was tempted to do more, just to save myself the trouble down the road. However I would be one short(10 in the kit, 11bolts), and my luck would leave my with that one stripped. :-)

Overall it went very well and I am pleased with the results. The kit was a little expensive, but it really saved me some time/trouble of unbolting the head and bringing it back to the machine shop.

Thanks for the responses none-the-less!-Jamie

[s13sr20chris]

hmmm, thread locker...good idea. i will have to try that sometime.

[slipnfall]

I talked to a buddy of mine today and he said the thread locker was overkill. In his experiance those things will never come out along w/a bolt. I didn't want to chance it either way.

I should note that after a day and a half of sitting w/the cover off, the thread lock still hasn't dried.(PA winter). I think it's because of the oil that was on the threads. Also it was super-runny, and I know they also make some in a gels/paste form, so that might be better. Just make sure it does dry fully if you use it: you might end up locking your bolt to the helicoil.

-Slip

[navysnail]

thread locker is anaerobic, meaning it will only cure in the absence of oxygen. also, it breaks down around 550 degrees F. (i think thats it). so if you have a bolt that has loctite on it, if possible heating it up with a propane torch will break down the locker making it easy to get it out