M42 valve cover plugs?

[Resurrector27]

Hello everybody, I have a question. I have tried searching around but haven't found much. I have recently acquired 1990 318i that I' am going to be taking the head off of. I took the valve cover off to take a peek at the cams and then I put the cover back on. I soon found out as well as a lot of other people have how easy it is to strip the head's threads. I say that a lot of people will just heli coil the thread and that solves the problem. What I was wondering is could I make a steel plug with a tapped hole and put that in the aluminum block? I just want to make sure the two materials will be okay with all the expansion and heat.

[varg]

You mean like a timesert? Just helicoil it. I did that to mine, it was easy and worked well.

[Fsnow]

Rather than making steel plugs you can buy steel inserts that are threaded inside and outside. I like Keyserts better than helicoils for any application. There are a few options such as keyserts, time serts, and likely others as well.

[varg]

Pointless to spend the extra money on timeserts and keyserts and such for such a low stress application. Even in the high stress applications it's pointless, helicoils are the standard for thread repairs in the aircraft industry. The off brand ones are fine for a valve cover.

[TobyB]

Except for things like exhaust studs, where Keyserts don't weld themselves to the
studs as badly, and back out. Or split inside the hole. That really sucks...

t
learned that one the hard way.

[Fsnow]

I don't know the difference in cost and I can understand that can be a factor. I use them daily at work on components for industrial engines, if something has a helicoil we take them out and replace with keyserts.
They can be tapped, they can be easily removed, they take more of a beating, you can get thin wall, or heavy wall and made of numerous materials.
I prefer them but thats just my opinion, do what you want.
It beats making your own plugs though

[Vanilla Gorilla]

I don't know the difference in cost and I can understand that can be a factor. I use them daily at work on components for industrial engines, if something has a helicoil we take them out and replace with keyserts.
They can be tapped, they can be easily removed, they take more of a beating, you can get thin wall, or heavy wall and made of numerous materials.
I prefer them but thats just my opinion, do what you want.
It beats making your own plugs though

Good info. Thanks!

[AndrewBird]

I prefer helicoils because they are cheap, proven and you can get them almost anywhere.

Whatever you use, do all the holes, not just the stripped ones. They all will strip eventually, so you might as well do them all at once.

[bmwman91]

I had helicoils in my head's valve cover bolt holes from 2005 - 2012 and not a single one had an issue. When I blew that engine, the replacement I got from Metric Mechanic also had Helicoils in there. If they are good enough for MM, then they are good enough for me.

With that said, if you want to go the TimeSert route, it certainly can't hurt.

[Resurrector27]

Thanks a lot guys! I' am probably just going to go with heli coils for now. The reason i9 would make my own plugs is because I' am in a CNC class at school so i could probably make a nice little production run of them.

[varg]

You should CNC an oil cooler/remote filter adapter that bolts on where the stock oil filter housing does.