[babek1]

Hey guys,

I have a 2006 330i (N52 engine), E90 and I recently had my water pump and thermostat replaced, at 87,000 miles. Since I had it replaced about 1.5 weeks ago, I noticed a gross smell coming from the engine area and I took it back to the shop that did the water pump replacement and they said the smell was likely from the anti-corrosion coating on the water pump which stinks, and that should go away shortly.

A few days later, today, I noticed that my onboard oil meter dropped to 75%, and then to 25%. Also, the smell from the engine area started turning into a burning oil smell. I put cardboard under the car, and there were many drops of oil after only 5 minutes of being parked. I used a flashlight to look into the engine area and there seems to be oiled soaked all over the bottom areas, and as high as the air intake box. I am currently having the car towed to the shop because I don't think it's safe to drive any more.

Anyone have similiar issues? Can a new water pump and thermostat cause such a huge oil leak? I ask because if it can, then I hope that the shop will assume responsibility and not charge for any repairs. Again, all of this began after the shop installed the new waterpump and thermostat.

Thanks,

[335ivin]

Its probably your valve cover gasket leaking this car are known for leaking from there. Mine started leaking around 80k miles a shit load to the point that it was not safe to drive it.

[Meeni]

Nop the water pump job is irrelevant. The valve cover, oil filter housing and to a lesser extent the main engine oil pan are well known to leak around your mileage. The OFHG does match your description of oil being spilled everywhere on the airbox. The VCG would more leak toward the exhaust without making a mess anywhere else but the seam area and where it drips on the exhaust tube.

[babek1]

Hey guys,

Just got an update, the issue was an engine bolt that came loose and is now gone, which is causing this massive leak. My shop said they've seen this before and that it's somewhat of a common issue with N52 engines. They also said it always seems to be the same bolt, which is the one near the oil filter housing.

On a side note, I am also getting my oil filter housing gasket replaced as well because they said that it didn't look that great. Will be cheaper to get that fixed now since they'll been working in that area anyway.

My question to you all is, have you ever heard of this bolt missing issue? How does a bolt even loosen up like that in the first place? I would think that heat would cause this, but I just got a new water pump and thermostat and I usually monitor the coolant temperature and it's always between 95C and 105C. Is it just a N52 design flaw?

Thanks in advance!

[babek1]

Originally Posted by babek1

Hey guys,

Just got an update, the issue was an engine bolt that came loose and is now gone, which is causing this massive leak. My shop said they've seen this before and that it's somewhat of a common issue with N52 engines. They also said it always seems to be the same bolt, which is the one near the oil filter housing.

On a side note, I am also getting my oil filter housing gasket replaced as well because they said that it didn't look that great. Will be cheaper to get that fixed now since they'll been working in that area anyway.

My question to you all is, have you ever heard of this bolt missing issue? How does a bolt even loosen up like that in the first place? I would think that heat would cause this, but I just got a new water pump and thermostat and I usually monitor the coolant temperature and it's always between 95C and 105C. Is it just a N52 design flaw?

Thanks in advance!

I'm finding several posts about broken and/or missing bolts:

http://www.bimmerfest.com/forums/sho...d.php?t=280142

http://www.e90post.com/forums/showth...aluminum+bolts

http://www.e90post.com/forums/showth...2+bolt+missing

Wow, is this the same issue as with my car? I'm finding that the ownership costs of my car are quite high....especially in the past year.

[Meeni]

Yes, it is very common. The bolt usually snaps and then it leaks.

[Yd330i]

137k and it just happend. It's common for n52 engines I guess they weren't torqued right and plus they'r aluminum one time use bolts... The shops said 600 to fix. I did it myself and just bought all the gaskets for 80. Saved a big chunk

[kisho]

I actually just replaced that exact bolt myself. Took me a few days to figure it out.

[Brian_TII]

On mine I just replaced the broken bolts. I didn't replace the gasket, just replaced the bolts. Hasn't leaked a drop in almost 5 years.