rebuilding m42

[///m42 sport]

Just picked up this spare m42 and trying to decide what I want to do with it.  the M42 in my car no possibly has a broken ring and is going through oil like crazy.  My thoughts are to clean up the spare m42, and if the sprockets are in good shape, replace the seals, and swap into my car. 

My other thought was to do a stock rebuild since this is going to be my daily.  Only thing is I've never worked on engines before so I'm pretty hesitant to do anything major with the engine. 

In the meantime, I'lll post up some pics of the cleanup progress.  Also I figure there are not enough pics of m42s online haha

[Darky]

If you can get a e36 m42 head.
They are better, 6 mm valve stems.
May as well port and as well. While your there.

Cheers

[mabeer]

I'd suggest a compression and leak-down test as well as checking crankshaft endplay.   That will give you some information to help make your decision.

[///m42 sport]

spent some more time tonight taking the engine apart




Looks Good!

plugs are worn haha


Not sure what happened here with the injector tip.  I searched everywhere thinking the tip flew off somewhere or inside the port but I didnt find it.  I'm thinking the PO installed the injector without the tip since when I pulled the injector out, the rubber washer was still in the hole.

Havent done a compression test yet though.

[///m42 sport]

btw how do you get the pulley off the crankshaft?  Does it just pull off?

[Darky]

By attaching something or someone to the flywheel end of crankshaft and yelling a lot!

[mabeer]

Cam sprockets look great!  

[///m42 sport]

removed the waterpump today.  thought it was weird there was no paper gasket...once removed noticed the a pretty good chip on the rim surrounding the waterpump where the PO just tried to fill in with silicone gasket maker. 

Now the question is how can I unbolt the crankcase to replace the timing cover with the engine on the stand? there is no flywheel I can use to stop the crankcase.   I only have hand tools btw

[mabeer]

You need a crank holder.  You can borrow it if you want just pay for shipping there and back.  I've also got a lower timing case cover from when I switched mine from the idler wheel to idler guide.  PM me if you're interested.

[///m42 sport]

I was also wondering if its possible to replace the profile gasket by removing just the upper timing cover?

[SkidMark]

Yes it is possible, but its hard to compress the profile gasket. You would have to use a jack or something to jack up the timing cover to compress the gasket. Never tried it personally but other poeple have done it. Sounds tricky to me because of the angle m42 blocks sit at, cant jack straight up... Good luck, ....Skid

[///m42 sport]

ok cool...  My engine is on a stand so maybe a little easier to do

[mabeer]

I know I PM'd this but I thought I'd post up for others that come after.  Google E30 Factory Manual and you'll find links to download the BMW Factory Manual that will walk you through the lower timing case replacement.  The M42 section is pretty good.

[///m42 sport]

Spent some time cleanging my engine up.  I was all excited last Monday to get the crank holder tool.  Waited a week to get it so I can finally get the lower timing case off.  Turns out Pelican shipped me the wrong tool.  I called them right away and then waited for 5 days, no response on what to do from them so I called them Friday.  Sent the tool back and another one should be on its way.  Hoping the same mistake doesnt happen twice. 




after removing my thermostat, I got to see the profile gasket which looked like it was in decent shape.     Guess I'll wont mess with it for now. 

also what do you guys suggest is best way to clean then paint the engine block?  Seems like the more I wire brush and scrub the more rust comes off. 

[doitover]

That bolt is on tight. I made my own crankshaft holder by drilling a couple of holes in a long piece of angle iron and using the ground under the car to hold it. On an engine stand I think it might flip the stand if it wasn't bolted to it. I had to use a 4 ft extension on a breaker bar to get mine off.