Blown head gasket or cylinder head crack?

Moderator: martauto

User avatar
gudgeon
E30 Zone Regular
E30 Zone Regular
Posts: 475
Joined: Sun Jan 27, 2008 11:00 pm
Location: Didcot

Post Mon Mar 19, 2012 10:07 am

M50B25

I've got plenty of white smoke under load and a very small amount of mayo around the oil filler cap.

No noticable oil in coolant or water in oil. I think the small amount of mayo is from blow-by.

Engine hasn't overheated.

On this engine is it likely to be cracked cylinder head or just a gasket?
DanThe
E30 Zone Team Member
E30 Zone Team Member
Posts: 28649
Joined: Sat Sep 10, 2005 11:00 pm
Location: Staffs

Post Mon Mar 19, 2012 2:17 pm

Cracked head is more common than gasket, is it using coolant?
capri_rob
Married to the E30 Zone
Married to the E30 Zone
Posts: 9678
Joined: Tue Feb 19, 2008 11:00 pm
Location: South Staffordshire

Post Mon Mar 19, 2012 2:20 pm

How often do you use the car ?

If its irregular use and short journeys you can get a buildup of mayo from that.

If the white smoke is there all the time though does sound like you have a potential issue.
Image

e30topless said : Proper BMW's have 4 headlights, last of the run was the E30 and E34/E32 anything after that is just complete shite
User avatar
gudgeon
E30 Zone Regular
E30 Zone Regular
Posts: 475
Joined: Sun Jan 27, 2008 11:00 pm
Location: Didcot

Post Mon Mar 19, 2012 2:23 pm

I'm pretty sure it's a problem.

I guess my real question is, are cylinder head cracks common compared to blown gaskets?
User avatar
gudgeon
E30 Zone Regular
E30 Zone Regular
Posts: 475
Joined: Sun Jan 27, 2008 11:00 pm
Location: Didcot

Post Thu Mar 29, 2012 8:57 am

An update on this, problem was very odd as I never saw oil in coolant, bubbles in coolant, coolant in oil.

However, the fuel tank was very low and had been for a long time (I don't use the car at the moment), when I topped up with 10 litres the problem went away. I'm pretty sure this was a water in the fuel tank issue, apparently not enough to cause misfire, but enough to cause noticable vapour.

Anyone think this sounds likely?