Oops...lol

[bmwman91]

Well, fingers are crossed for you that it was just the busted guide or something else minor!

[jntar]

Yikes. Well, it's good that you are willing to do your due diligence and check things properly. If the bottom end is yucky...maybe it's time for a stroker?

Honestly I don't have the money right now. My flight training has demolished any type of budget I once had.


On another note. I drained the oil through a filter and found no metal. I did find two small chunks of plastic from the bottom timing guide. Still waiting to pick up that hoist. In the mean time I have placed the turbo kit up as a tentative sale. If the motor work ends up being minor I'll keep it, if it's a full rebuild it's getting swapped for an s50. Love the turbo m42 but sometimes you have to do what's financially reasonable.

[bmwman91]

Already gave the idle sprocket a good look over. Its in good shape. I did not replace the timing equipment yet. I was doing it now, but with the knocking coming from elsewhere Im holding off.

Picking up a hoist to hold the motor while I remove the upper pan. I want to check out the bearings before I go any further. It's not looking good.

Yikes. Well, it's good that you are willing to do your due diligence and check things properly. If the bottom end is yucky...maybe it's time for a stroker?

[glucklich21]

Well damn. Time for a cheater pipe then.

[jntar]

A pipe wrench and some turning with it will be your friend. I've had two M42s that have done the exact thing.

Tried that lol! That's where the scarring on the pump housing came from

[glucklich21]

A pipe wrench and some turning with it will be your friend. I've had two M42s that have done the exact thing.

[jntar]

Since you are in there, take a very close look at the timing case casting around the idler sprocket. It is not uncommon to have the idler gear snap off of the boss it mounts to...happened to me, and from looking at things after the fact, I might have been able to see the crack before it broke if I had known.

So you replaced all of the guides and stuff and it still makes the noise?

Already gave the idle sprocket a good look over. Its in good shape. I did not replace the timing equipment yet. I was doing it now, but with the knocking coming from elsewhere Im holding off.

Picking up a hoist to hold the motor while I remove the upper pan. I want to check out the bearings before I go any further. It's not looking good.

[bmwman91]

Since you are in there, take a very close look at the timing case casting around the idler sprocket. It is not uncommon to have the idler gear snap off of the boss it mounts to...happened to me, and from looking at things after the fact, I might have been able to see the crack before it broke if I had known.

So you replaced all of the guides and stuff and it still makes the noise?

[jntar]

How do you cams and tensioner look?

Cams are clean and smooth. Did a head gasket less than 1k miles ago and they are exactly the same as last seen.
Tensioner has 15k miles on it and looks good as well. I was able to compress the oil out of it and it still extends as intended.

I bought a new large rail, tensioner rail, tensioner and lower guide hoping one of those were the problem. However the noise moved from the front of the head to the center of the head when I removed the valve cover.

You can hear the knocking while cranking.

[bmwm42]

How do you cams and tensioner look?

[jntar]

Did you check your oil pressure?

I did not. I have a gauge and it never appeared to be low.

[bmwm42]

Did you check your oil pressure?

[jntar]

Did you check the idle gear

No play, all bearings there and clean. One of the first things I checked.

time to bust out the propane torch

Slide hammer first. Then torch if that doesn't work.

[Dj Buttchug]

time to bust out the propane torch

[bmwm42]

Did you check the idle gear