Rounded distributor cap bolt - Help needed please!!

[otE30touring]

I'm part way through doing a timing belt change on my 1989 320i and am trying to remove the distributor cap. I've managed to get the upper mounting bolt for the cap out but the lower one has been completely rounded off. I've tried everything to get it off but am having no luck unfortunately.

I'm curious to know if anyone else has had the same issue as given the size of the head of the bolt I wouldn't be surprised if this was quite common.

If anyone has any advice at all as how best to approach this I'd be really grateful as I'm losing motivation on this very fast now having hit multiple issues so far.

Thanks in advance!

[hennabm]

I had the same problem with mine a few years ago. I was able to use some long nose mole grips to get hold of it and gently ease it out. It took time but got there in the end.

Another way may be to take a Dremel or similar and grind off the head and with the cap off then remove the remaining shaft.

Fit a new cap afterwards and make sure the threads are oiled so it will come apart next time.

[otE30touring]

I had the same problem with mine a few years ago. I was able to use some long nose mole grips to get hold of it and gently ease it out. It took time but got there in the end.

Another way may be to take a Dremel or similar and grind off the head and with the cap off then remove the remaining shaft.

Fit a new cap afterwards and make sure the threads are oiled so it will come apart next time.

Thanks a lot for the reply!

After spending quite a while thinking, in the end I did exactly that, took a dremel and basically remade the head of the bolt into a 7mm and it finally came off. Part of the cap did break and I had issues with the rotor bolts underneath being very seized up as well which meant the rotor itself also broke in two. Will definitely add a drop of oil to each when I put them back on.

Looks like a new cap and rotor but that's definitely not a bad thing!

[Brianmoooore]

Oil is for lubricating bearings - copper grease is for preventing fixings from corroding in place. Oil in a blind ended threaded hole can also cause a hydraulic lock, preventing the bolt from being screwed fully home, or even splitting the casting.

[martauto]

Oil is for lubricating bearings - copper grease is for preventing fixings from corroding in place. Oil in a blind ended threaded hole can also cause a hydraulic lock, preventing the bolt from being screwed fully home, or even splitting the casting.

Excellent Brian, you got there before me. lol

Mart.