[W37V]

So after replacing the valve cover gasket yet again, I was installing valvetronic motor and I think I stripped holes that hold it in place. After hand tightening them, I try to use torque wrench at 7ftlb and screw just started spinning. Now, I don’t know what to do. I could try to squeeze a bigger bolt in there, but not sure how that’s gonna work out. Or I could try to fill in the hole somehow and then reuse the same bolt. Next bigger bolt would be 1/4 28 or m7.

Can I use lock tite? Any advice is appreciated. Never dealt with this before and want to get it right.

Fuck my life.

[desertman123]

Might be able to helicoil it

[nsjames]

helicoil is the correct solution, assuming the metal inserts are large enough to take the drill and tap.

sadly you really should pull the cover again to fix it. You don't want to drop metal bits into the valvetrain.

[Biginboca]

Are you sure the bolts themselves aren’t what’s messed up?

Not sure about the valvetronic bolts but a lot of the bolts are aluminum so maybe it’s the bolts and you can just get some new ones form your dealer.

[W37V]

Originally Posted by desertman123

Might be able to helicoil it

Originally Posted by nsjames

helicoil is the correct solution, assuming the metal inserts are large enough to take the drill and tap.

sadly you really should pull the cover again to fix it. You don't want to drop metal bits into the valvetrain.

You wound't happen to be near DC by any chance?

Never done helicoil. Do you have any advice which one (kit) to use?

And removing valve cover again is just peachy... fuck.

I am just so frustrated. Anyone wanna make some $ by helping me with this?

[W37V]

Originally Posted by Biginboca

Are you sure the bolts themselves aren’t what’s messed up?

Not sure about the valvetronic bolts but a lot of the bolts are aluminum so maybe it’s the bolts and you can just get some new ones form your dealer.

Took bolts out and threads on them look brand new.

[cwlo]

pretty sure the bolts are steel, and they probably go into aluminum. Its kind of a tricky setup in that there isn't much room to get a e-torx socket in there. Anyway, definitely take the valve cover off and evaluate. You certainly don't want that motor loose and then have it strip the cog.

Actually, if you pull the motor/actuator and seal, you should be able to get a good look at the threads and what's going on.

[W37V]

Originally Posted by cwlo

pretty sure the bolts are steel, and they probably go into aluminum. Its kind of a tricky setup in that there isn't much room to get a e-torx socket in there. Anyway, definitely take the valve cover off and evaluate. You certainly don't want that motor loose and then have it strip the cog.

Actually, if you pull the motor/actuator and seal, you should be able to get a good look at the threads and what's going on.

I don't think motor would be lose as there is the 3rd bolt holding it in place, but it would definitely leak.

I will take a look and report. Drilling makes me nervous.

[Joebie]

I can't remember exactly what that area looks like but could you perhaps instead of heli-coiling, could you just run a 1/4-20 tap through there and use slightly bigger screws (1/4-20 instead of M6)?

The bolts that hold the valvetronic motor in are probably M6, right? so if you strip an M6, you're left with a hole that's about .23in diameter. Tap drill size for 1/4-20 is .22in. So you're a little oversized but still would probably have some threads to hang on to.

You might also have to modify the motor and gasket to accomodate, but I kinda dont like heli-coils. Even if my idea fails you can always step up to a helicoil size no problem.

You WILL have to take the cover back off. You must make sure no metal shavings end up in the camshaft area. You must be sure that when you drill or tap, you are as perpendicular as possible to the valvetronic motor mounting face. You have 1, maybe 2 shots at fixing this before its time to put a new head on there. Maybe having a welder come in is a possible other way to fix this if you need it.

you've learned it the hard way now, but sometimes its best to just snug things by hand, lol.

Best of luck to you!

EDIT: I've changed my mind, but I left my original idea there in case you like it. I think Heli-coil is the way to go after looking on google for some picture of the area. Its just too cramped in there to use a bigger screw. There's a few different types of heli-coils, but the most common is the tanged kind like this.

https://www.amazon.com/Helicoil-5546...6+helicoil+kit

PLEASE NOTE!!!!! I AM NOT SURE IF THAT'S THE RIGHT SIZE! I THINK IT IS BUT IM NOT 100% SURE!

Read more on heli-coil installation here.

http://knowhow.napaonline.com/know-h...licoil-insert/

[gT-BMW]

damn i hate when that happens.

try using a thread chaser with the correct thread and pitch as the bolts. If you find the right size thread chaser but it isnt the same as the thread and pitch of the bolts, you will have to use new bolts that match the chasers thread and pitch. also soak the chaser with atf because the metal shavings will stick to the atf covered chaser. work it back and forth. make one pass clean, soak in atf and continue.

helicoil will solve the issue and also solve future cross threading issues.

[W37V]

Originally Posted by Joester

I can't remember exactly what that area looks like but could you perhaps instead of heli-coiling, could you just run a 1/4-20 tap through there and use slightly bigger screws (1/4-20 instead of M6)?

The bolts that hold the valvetronic motor in are probably M6, right? so if you strip an M6, you're left with a hole that's about .23in diameter. Tap drill size for 1/4-20 is .22in. So you're a little oversized but still would probably have some threads to hang on to.

You might also have to modify the motor and gasket to accomodate, but I kinda dont like heli-coils. Even if my idea fails you can always step up to a helicoil size no problem.

You WILL have to take the cover back off. You must make sure no metal shavings end up in the camshaft area. You must be sure that when you drill or tap, you are as perpendicular as possible to the valvetronic motor mounting face. You have 1, maybe 2 shots at fixing this before its time to put a new head on there. Maybe having a welder come in is a possible other way to fix this if you need it.

you've learned it the hard way now, but sometimes its best to just snug things by hand, lol.

Best of luck to you!

EDIT: I've changed my mind, but I left my original idea there in case you like it. I think Heli-coil is the way to go after looking on google for some picture of the area. Its just too cramped in there to use a bigger screw. There's a few different types of heli-coils, but the most common is the tanged kind like this.

https://www.amazon.com/Helicoil-5546...6+helicoil+kit

PLEASE NOTE!!!!! I AM NOT SURE IF THAT'S THE RIGHT SIZE! I THINK IT IS BUT IM NOT 100% SURE!

Read more on heli-coil installation here.

http://knowhow.napaonline.com/know-h...licoil-insert/

I checked the size, and the next size up would be 1/4 28. I think it's slightly larger than m6. If I just run the new thread, i think it could work. Drilling makes me nervous as the hole is under angle and I have never done this before. I wouldn't mind paying someone to get this done right.

Not that it matters, but for the record. I did hand tighten it. It felt fine, but i just wanted to check if it was tight to spec. So, I used tq wrench at 7ftlb to check and the bolt just started spinning.

[W37V]

Originally Posted by gT-BMW

damn i hate when that happens.

try using a thread chaser with the correct thread and pitch as the bolts. If you find the right size thread chaser but it isnt the same as the thread and pitch of the bolts, you will have to use new bolts that match the chasers thread and pitch. also soak the chaser with atf because the metal shavings will stick to the atf covered chaser. work it back and forth. make one pass clean, soak in atf and continue.

helicoil will solve the issue and also solve future cross threading issues.

Maybe finding a longer bolts would be a solution. Bolts are about 1cm long now. If I find one that is 1.25cm, i think there might be enough thread on there to hook up. But wish me luck finding such bolt.

Maybe a solution could be to use the same method as on n46 engine - two nuts on the back end and longer bolt - if there is enough clearance.

See this video - at 16 sec mark

[Joebie]

Originally Posted by W37V

Maybe finding a longer bolts would be a solution. Bolts are about 1cm long now. If I find one that is 1.25cm, i think there might be enough thread on there to hook up. But wish me luck finding such bolt.

Maybe a solution could be to use the same method as on m52 engine - two nuts on the back end and longer bolt - if there is enough clearance.

Yeah but how do you actually get the nuts on there? The valve cover's gotta go on before the valvetronic motor.

You're right that 1/4-28 would be more suitable. For a given percentage thread, the 1/4-28 has a larger tap drill size than 1/4-20.

Longer bolt might work, you're right. Just buy a bolt that's too long and then grind/cut it down to the perfect length, easy. I personally wouldn't feel too great about this solution. We were taught while I was in school for my BS in mechanical engineering that the threads need to be 2x the diameter of the bolt in order to hold appropriately. So for a 6mm bolt you'd need 12mm of thread engagement for proper strength. Of course you can have less and its not the end of the world, but id start to get skeptical anything less than like 5-6mm of thread.

I still feel as though heli-coil is the way to go though.

A good way to get a drill to be perpendicular to weirdly angled surfaces is to use a drill guide like this, you can obviously make your own with a drill press or maybe by cutting up a piece of metal with a known-square hole.

[W37V]

Originally Posted by Joester

Yeah but how do you actually get the nuts on there? The valve cover's gotta go on before the valvetronic motor.

The plan would be to use something like JB weld and longer bolts.

Put a bit of JB weld on there to hold nuts. Use a bolt to hold the nut in place while putting on the valve cover. Once the valve cover is on, remove the bolt and insert a new one - longer. Nuts need to hold on place just long enough to put new bolts in.

This is all under assumption that the hole is pass through and there is enough clearance for the nut.

Welding those nuts would be perfect, as that would ensure serviceability in the future.

[Joebie]

Originally Posted by W37V

The plan would be to use something like JB weld and longer bolts.

Put a bit of JB weld on there to hold nuts. Use a bolt to hold the nut in place while putting on the valve cover. Once the valve cover is on, remove the bolt and insert a new one - longer. Nuts need to hold on place just long enough to put new bolts in.

This is all under assumption that the hole is pass through and there is enough clearance for the nut.

Welding those nuts would be perfect, as that would ensure serviceability in the future.

This should be your last resort, that's a pretty ghetto fix. It'd probably work once but god forbid you even have to take it back apart and service it, or some JB weld chunks break off into your engine.

[nsjames]

the JB weld will eventually come off. THe oil will seep into the seam eventually. I've used it to patch an oil pan and you get about 6 months before it falls off, and that was a clean steel pan. No Idea how it would stick to plastic/aluminum.

drilling out the inserts for a helicoil shouldn't require a giud or anything else. The bit will center on the existing hole. Just try and keep the bit perpendicular and it will be fine.
I had to helicoil one of my transmission pan bolts., it's held fine for 35K miles. It's a permanent solution if done properly.

[W37V]

Originally Posted by Joester

This should be your last resort, that's a pretty ghetto fix. It'd probably work once but god forbid you even have to take it back apart and service it, or some JB weld chunks break off into your engine.

I am really uncomfortable with drilling the hole, due to likelihood of error. For the "nut" approach, I would use just a bit of high-temperature, high-strength JB just to hold the nut in place.

Nut approach is still theoretical as I am not sure if there is clearance.

hassmaschine , you said you had a n52 head sitting around. Do you mind taking a look at this and seeing what would be the right approach?

Thanks

[dwashy]

I understand this is probs very scary to you now, but you'll likely look back in the future and see the humor. I did this once with an overzealous hand and impact wrench, when installing subframe bushings. Just take your time, and be deliberate. Helicoil or larger bolt is likely your best option

[Joebie]

Drilling is going to be way lower risk than JB-weld in this case, in my opinion.

Remember, if you mess up the drilling, you can still do your JB weld method, so you might as well at least try the non-ghetto heli-coil method no matter how scared you are about it. It's not going to be as hard as you think though if you take your time with it.

[Biginboca]

I agree do the helicoil first. If that doesn’t work, which it will, then you can drill the hole and have someone tac weld a nut on the backside. Do not mess with JB weld that’s just a bad idea in this application IMO.

[Efthreeoh]

Pull the valve cover. Drill the holes to the next metric size up M8 I think, and retap the holes. You'll need to get the M8 tap, so try to find a "kit" that has the metric dimensional (i.e. not fractional) drill to size the hole correctly along with the tap. If memory serves there is plenty of material on the mating plate on the cylindehead the Valvetronic motor mounts to to drill the next size up.

Use heavy grease on the drill bit and tap to collect any chips that come out. Stuff a shop towel behind the plate to catch anything that the grease may not pick up.

Or if you are concerned that you don't have the skill set for such work, have the car towed to a mechanic who can do such work. It will be far cheaper to have a shop do a heilcoil insert than to replace the head if you botch the repair. I doubt there is any tolerance for the valvetronic motor to not be correctly aligned to the cylinderhead.

My 2 cents.

[Efthreeoh]

Are you near DC you said?