Removing the head on an NVM50

[lolcantturn]

Embarassingly long story short, due to bad decision making, we dropped my M50 to the ground from about a foot high and the head has a hairline fracture on the sensor in the front, above the thermostat. It doesn't look like it will prevent the motor from running but..I don't know
I've removed an M20 head multiple times and have got it down a science now, I'm terribly clueless about M50's in every aspect. The plan is to take it to a machine shop. So in comparison to an M20 head removal, how difficult is an M50 one? We Pulled the valve cover and got to the whole cams setup and stopped there since we were too uncomfortable to proceed removing any more bolts.
I'll need a new HG and head bolts I assume? (just did that all the time on the M20)

[Jand3rson]

I'll need a new HG and head bolts I assume? (just did that all the time on the M20)

Ummm, and a new head...

[bimmerteck]

a good shop should be able to weld it up if it's not going to effect the combustion chambers, not usually pretty but I've salvaged some heads damaged in accidents that way.

[Jand3rson]

Hmmm, interesting. What's the average cost of of that though, versus locating a new head?

[lolcantturn]

Ummm, and a new head...

Not quite. It's a hairline fracture with plenty of room for repair. In all honesty, I don't even think it would affect anything too dramatically.

a good shop should be able to weld it up if it's not going to effect the combustion chambers, not usually pretty but I've salvaged some heads damaged in accidents that way.

Yep it's not affecting anything at all almost

Hmmm, interesting. What's the average cost of of that though, versus locating a new head?

We could get it done for less than $100 I'm sure. My friend knows the machine guy and its not even an extensive repair

[greyis89]

I have a set of brand new m50 head bolts for sale. Still in package. Lmk if you machine a need a set for cheap, I need to get rid of them. Good luck, sorry about the setback.

[Jand3rson]

Crazy. Consider me schooled.

[shiboujin]

Get a whole head gasket kit. You might as well regasket everything you are going to be removing anyway. Mainly the intake and exhaust gaskets.

Unless you have access to a snap on man or a REALLY good tool shop, you'll have to remove the cams to get access to the head bolts. There is a BMW tool to hold the cams but fuck that. Do a quarter turn on each cam cap nut in order all the way down the line until the nuts come off. If you stress out the cam by taking a few nuts off too quickly, you'll snap the cam. The rest is M20 like.

Re-installation is obviously reverse of removal. You will need to line the crank to cam sprocket properly. I forget how it goes. Some NV only let you put it on 1 way anyway.

Again, there is another cam locking. tool to align the cams but F that. Make sure the motor is TDC (before even pulling the head). Look at the rear of the cams. You'll see that they are square. One of the 4 sides has 2 dots dimpled into them. On both cams, these need to point up. Take a flat edge and lay it across both of the back parts of the cams. Your aim is to get both of them flat. IE you can't see past them, they are both the same angle. Tada! You cheaply timed your M50. I've done this on 4 different occasions and each engine still runs fine.

I left out many details... you should be able to get most of the way through it with this though. I'm also sure someone else has written it up around here somewhere.

[e30s50dan]

^^^. What he said

[lennon]

you can definitely get to all the head bolts on an m50 without taking the cams out. save the hassle. no snap-on tools needed.

[brokenbimmer533]

you can definitely get to all the head bolts on an m50 without taking the cams out. save the hassle. no snap-on tools needed.

+1 I used a deep socket and 6 inch extension. Got the old ones out and new ones in that way.