[alx.]

Hello Guys,

I've installed two new vanos solenoids a few months ago and i noticed the top bolt doesn't torque well(you can turn it by hand) so i'm guessing that oil vapors are escaping, what can be done about the nut? I tried interchanging them and only the top one is loose, will i need to modify the engine block somehow?

[Three_thirty_I]

And you fitted it with a new O-ring seal?

That looks dirty like an old engine that had never been cleaned for such a short period of time. So there must be a fairly significant leak. I would start by cleaning this with a brush and some petrol, or any decent light solvent cleaner. Maybe also clean the electrical connectors for the solenoids to play safe. Do you think the thread is stripped for either bolt or most likely the head where it screws into? These bolts don't really need to be all that tight, just enough to keep the solenoids in place.

[alx.]

Originally Posted by Three_thirty_I

And you fitted it with a new O-ring seal?

That looks dirty like an old engine that had never been cleaned for such a short period of time. So there must be a fairly significant leak. I would start by cleaning this with a brush and some petrol, or any decent light solvent cleaner. Maybe also clean the electrical connectors for the solenoids to play safe. Do you think the thread is stripped for either bolt or most likely the head where it screws into? These bolts don't really need to be all that tight, just enough to keep the solenoids in place.

New o-rings for both! The thread is stripped from the head for just the top bolt and it won't screw in properly... you can endlessly screw it in with no avail and i believe that's the problem....what can be done?

I think this might be causing my rough running as well.

[alx.]

Cleaned the connectors with a special circuit cleaner. The solenoid seems to be air tight and you can't remove it by hand easily, the nut though you can turn by hand and remove freely.







Would a helicoil insert fix this?

[JuniorB]

HI,I wouldn't go that route yet,don't go drillin just yet,clean the threads with brake cleaner,blow with air,new bolt with pipe dope. The dope will harden enough for the bolt not to back out. You can use a mild loctite if you don't use dope. It's worked for me with aluminum. Hope this helps

[Efthreeoh]

You need to fix this properly. The thread in the cylinderhead is stripped and needs to be repaired correctly. The proper repair is a heilcoil insert. I recommend that you leave it to a professional and take the car to an automotive machine shop to have the helicoil repair made.

The leaks are coming from the oil pressure that is present in the head and the VANOS solenoid needs to be firmly affixed to the cylinderhead.

[alx.]

Originally Posted by JuniorB

HI,I wouldn't go that route yet,don't go drillin just yet,clean the threads with brake cleaner,blow with air,new bolt with pipe dope. The dope will harden enough for the bolt not to back out. You can use a mild loctite if you don't use dope. It's worked for me with aluminum. Hope this helps

I didn't know that! I will get some pipe dope, really appreciate the input.

[alx.]

Originally Posted by Efthreeoh

You need to fix this properly. The thread in the cylinderhead is stripped and needs to be repaired correctly. The proper repair is a heilcoil insert. I recommend that you leave it to a professional and take the car to an automotive machine shop to have the helicoil repair made.

The leaks are coming from the oil pressure that is present in the head and the VANOS solenoid needs to be firmly affixed to the cylinderhead.

Could this also affect the driveability of the car?

[Efthreeoh]

Originally Posted by alx.

Could this also affect the driveability of the car?

I would think so. The VANOS solenoids control the flow of oil to the VANOS adjusters that control the camshafts. If the solenoid is not sitting firmly in head, the oil is not going to flow correctly. Plus, the situation is only going to get worse to the point where the hole may not be able to be repaired. If you need to go the next bolt size up (M8) there my not be enough material to support a 8MM hole in the head.

[alx.]

Originally Posted by Efthreeoh

I would think so. The VANOS solenoids control the flow of oil to the VANOS adjusters that control the camshafts. If the solenoid is not sitting firmly in head, the oil is not going to flow correctly. Plus, the situation is only going to get worse to the point where the hole may not be able to be repaired. If you need to go the next bolt size up (M8) there my not be enough material to support a 8MM hole in the head.

This was extremely helpful, thank you sir i shall get it fixed this week.

[Three_thirty_I]

I would also rather have this properly fixed. I have removed and cleaned the solenoids a few times on my car, and only replaced the one O-ring and spacer some years back when the spacer fell off the end of the solenoids when I was removing it - found it months later "hiding" in the cooling fan shroud. Point is, the O-rings are still original for the one, and years old for the other, and the solenoids have been removed a few times for cleaning. But the engine is still spotless with not a trace of oil leaking out. It's not so much about the bolt having to be tight, but it has to keep the solenoids firmly in position. Good luck with the repair!!!

[Efthreeoh]

Originally Posted by alx.

This was extremely helpful, thank you sir i shall get it fixed this week.

Good. Now a bit of caution. Make sure you tell the machine shop to keep the hole that the solenoid fits into plugged so as to not drop anything into the timing chain housing. On the N52 the timing chain housing is integral to the engine block, meaning if something gets in the timing chain housing there is no cover to remove to open up the housing like on most engines. You'd have to drop the oil pan and hope whatever fell into the timing chain housing, fell down into the oil pan.

Good luck with it.

[Three_thirty_I]

Originally Posted by Efthreeoh

Good. Now a bit of caution. Make sure you tell the machine shop to keep the hole that the solenoid fits into plugged so as to not drop anything into the timing chain housing. On the N52 the timing chain housing is integral to the engine block, meaning if something gets in the timing chain housing there is no cover to remove to open up the housing like on most engines. You'd have to drop the oil pan and hope whatever fell into the timing chain housing, fell down into the oil pan.

Good luck with it.

Exactly! They are going to have to be very very careful not to allow anything to fall into the engine when doing this!!

[alx.]

Got it fixed, thank you people!

[Efthreeoh]

Helicoil?

[alx.]

Originally Posted by Efthreeoh

Helicoil?

Yes sir, also while looking around i noticed that one of the solenoid wires is chewed up? I'm not sure if it was from the heat or if i'm having a rodent problem but i do have some rough idle/stalling/check engine with mass air flow error(i changed the maf with a brand new one weeks ago). Any input?

[fa1rldy]

Originally Posted by alx.

Yes sir, also while looking around i noticed that one of the solenoid wires is chewed up? I'm not sure if it was from the heat or if i'm having a rodent problem but i do have some rough idle/stalling/check engine with mass air flow error(i changed the maf with a brand new one weeks ago). Any input?

Did you do the repair yourself? If so, I could use some pointers and tips. I have the exact same problem as you. Stripped the head when re-installing the intake solenoid yesterday.

I've been researching and it seems the m6x1 heli-coil would be compatible with the BMW m6x12-8.8 hex bolt, can you confirm?

Also, did you have enough space to do the drilling and tapping without removing any components?

Not sure about your rough idle, perhaps scanning for fault codes would narrow down the problem. My rough idle had different causes on two separate occasions. The first was cracked engine valve cover, the second was bad ignition coils.

[Three_thirty_I]

Glad you got this sorted out. Regarding the chewed cable, is it badly chewed such that it may not carry power to the solenoid, or just the insulation is damaged exposing the wires?

[alx.]

Originally Posted by fa1rldy

Did you do the repair yourself? If so, I could use some pointers and tips. I have the exact same problem as you. Stripped the head when re-installing the intake solenoid yesterday.

I've been researching and it seems the m6x1 heli-coil would be compatible with the BMW m6x12-8.8 hex bolt, can you confirm?

Also, did you have enough space to do the drilling and tapping without removing any components?

Not sure about your rough idle, perhaps scanning for fault codes would narrow down the problem. My rough idle had different causes on two separate occasions. The first was cracked engine valve cover, the second was bad ignition coils.

My garage did it, i will ask them and let you know Thanks for the advice, noone can point to what's the problem.

Originally Posted by Three_thirty_I

Glad you got this sorted out. Regarding the chewed cable, is it badly chewed such that it may not carry power to the solenoid, or just the insulation is damaged exposing the wires?

Apparently only the cable was chewed, the wires were fine... back to the drawing board.

[Three_thirty_I]

Originally Posted by alx.

My garage did it, i will ask them and let you know Thanks for the advice, noone can point to what's the problem.



Apparently only the cable was chewed, the wires were fine... back to the drawing board.

That's at least good news - not keen on damaged wires, at least you can cover them with some insulation.

[fa1rldy]

Originally Posted by alx.

My garage did it, i will ask them and let you know Thanks for the advice, noone can point to what's the problem.



Apparently only the cable was chewed, the wires were fine... back to the drawing board.

Was able to repair after two attempts. The m6-1 threaded insert was a perfect fit. I only removed the engine cover and front air intake so I had to spend a few days to find a compact right angle attachment and a stubby hex base 1/4 inch drill bit to drill out the hole which was the hardest part.

[alx.]

Originally Posted by fa1rldy

Was able to repair after two attempts. The m6-1 threaded insert was a perfect fit. I only removed the engine cover and front air intake so I had to spend a few days to find a compact right angle attachment and a stubby hex base 1/4 inch drill bit to drill out the hole which was the hardest part.

Great to hear mate, damn these aluminium covers.