Slow oil leak - Where to start?

[2ndName]

Hey guys,

New to the e30 world but am ready to tackle my first issue. Noticing a slow oil leak on my e30 318i. Any tips on how to go about locating the root cause? I can take pics if need be.

Thanks guy.

[rasputin]

spray the motor down with brake clean, put dye in the oil, wait a week or two, UV that shit!

leaks go from high to low, check valve cover first.

[2ndName]

Ah nice idea, thanks!

[Robotin]

depending on what year 318. 89+ m42 DOHC.

89- m10 SOHC.

most likly its the oil pan gasket. they rarely get changed. or its the Cam seal.

just try and trace it back.

dyeing oil and spraying down the whole engine seems like a alot of work. which may lead to a very small resolution.

plus i just imagine having oil and dye all over the place.

[Vivek]

^Umm, not really. Anything could be leaking, and just replacing something because it's unlikely that it's been changed is fucking stupid. Get the engine warm, spray it with degreaser, hose it off. Repeat a couple times til it's clean, then trace the leak to the source and replace what for sure is leaking. If it's the upper oil pan gasket, changing that is a lot more work than cleaning the engine and actually finding the source of the leak.

[b*saint]

Doesn't an M42 have a oil cartridge or was that only on an e36? If so that oil filter housing leaks or the bypass valve orings leak.

[Robotin]

^Umm, not really. Anything could be leaking, and just replacing something because it's unlikely that it's been changed is fucking stupid. Get the engine warm, spray it with degreaser, hose it off. Repeat a couple times til it's clean, then trace the leak to the source and replace what for sure is leaking. If it's the upper oil pan gasket, changing that is a lot more work than cleaning the engine and actually finding the source of the leak.

oil pan gaskets arent that bad. time consuming yes. frustrating yes. but hard to do, no.

plus like 90% of e30 leaks from the cam seal or oil pan. and spending all day washing 25 years of caked on muck is no fun.

[Vivek]

I'd rather spend all day properly diagnosing an issue than spend all day arbitrarily replacing a gasket that could potentially be leaking.

[mrcheezle19]

I'd rather spend all day properly diagnosing an issue than spend all day arbitrarily replacing a gasket that could potentially be leaking.

qft.