m52 sump removal in situ

Moderator: martauto

User avatar
Supafly
E30 Zone Regular
E30 Zone Regular
Posts: 559
Joined: Wed Feb 22, 2006 11:00 pm

Post Wed Mar 07, 2012 1:57 pm

I've had a problem with a rattle from my m52 at trailing throttle around 2700rpm for a while now which is documented in another thread. After testing and trying lots of different things I'm now at the point where I want to take the sump off to check the big end bearings.

I've jacked up the engine as high as I can and removed the engine mounts and chocked the engine. However as I started to take the 10mm bolts off I noticed two recessed in the bell housing, there is only about 2mm clearance between the edge of the bolt and the flywheel. I cant seen to get a socket onto the bolts and as they are recessed a spanner isn't much good either.

It almost looks as though there isn't enough room to turn the bolt... any ideas as I don't want to take the engine and box out to split it....

Thanks for reading :)
DanThe
E30 Zone Team Member
E30 Zone Team Member
Posts: 28649
Joined: Sat Sep 10, 2005 11:00 pm
Location: Staffs

Post Wed Mar 07, 2012 2:10 pm

If its an M20 flywheel and its been machined to clear the back of the sump you will be fine, if its not been machined and the sump has had some grinder action you will probably have to remove the gearbox/clutch/flywheel as it will be very tight, even if you do manage to get them out it will be more of a chore to get them back in
User avatar
Supafly
E30 Zone Regular
E30 Zone Regular
Posts: 559
Joined: Wed Feb 22, 2006 11:00 pm

Post Wed Mar 07, 2012 4:05 pm

Looks like it has had some grinder action as there is only about 2mm clearance and the bolts themselves look like they may have been kissed by the disc of death...

Thought I was saving time by buying a ready converted car!

I'm not going to bother taking the engine out, I'll try swapping the coils to see if the noise follows it and if not then I'll drive it til it throws a rod or knocks its knackers off. Get another engine and do it properly myself.
:(
User avatar
Supafly
E30 Zone Regular
E30 Zone Regular
Posts: 559
Joined: Wed Feb 22, 2006 11:00 pm

Post Sat Mar 10, 2012 3:25 pm

A friend of mine suggested drilling the heads off... I'll give it a try this week when I get a chance. Then replace with alen bolts of the same spec.
DanThe
E30 Zone Team Member
E30 Zone Team Member
Posts: 28649
Joined: Sat Sep 10, 2005 11:00 pm
Location: Staffs

Post Sat Mar 10, 2012 5:45 pm

Good idea if you can get a drill long enough
User avatar
Supafly
E30 Zone Regular
E30 Zone Regular
Posts: 559
Joined: Wed Feb 22, 2006 11:00 pm

Post Tue Mar 20, 2012 1:30 pm

Don't need too long a drill bit.
For future reference, I bought a dewalt 8mm hss bit from screwfix about 80mm long but you only need about 60 to do the job. I'll double check and edit the correct details.

Then once they're drilled the sump won't want to come off!!!

I had to take off the power steering pump pully and remove the bracket so that the sump could move forward and down enough to clear the bell housing and the two long bolts with no heads that are now hanging down.

So it is do-able but a pain.