Oil leak

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Topround
Posts: 27
Joined: Dec 31, 2020 11:50 AM
Location: New Jersey

Oil leak

Post by Topround »

Hey all, I just got my 535i running again and I’ve noticed that since it has started running, there’s a massive leak on the passenger (right) side of the engine, this only started when the engine started running, before that was dry underneath. I’ve replaced the valve cover gasket already, and I’ve noticed there’s a lot of oil coming from about halfway up the engine.

If it were the Pan gasket leaking I’d imagine that it would be leaking a lot from both sides, not just the passenger. Do any of you guys have any ideas as to where I sold start looking? Does this car have an oil cooler that has lines that can fail?
BMWCCA2
Posts: 3728
Joined: Feb 12, 2006 1:00 PM
Location: Central Virginia

Re: Oil leak

Post by BMWCCA2 »

Front? Back?

Lots of possibilities. On mine it was the upper timing-case gasket. :dunno:
Topround
Posts: 27
Joined: Dec 31, 2020 11:50 AM
Location: New Jersey

Re: Oil leak

Post by Topround »

Looks to be dripping from close to the front of the motor, not entirely. Getting underneath the car, looks as if it’s been dripping for a long long time, everything’s caked in oil, will have to dump a few cans of brake clean to continue diagnosis I guess. I can barely see the back of the AC Compressor with how much oil is caked onto it.
vinceg101
Posts: 4253
Joined: Jun 20, 2007 2:40 AM
Location: Los Angeles, CA

Re: Oil leak

Post by vinceg101 »

Topround wrote: Apr 04, 2021 9:23 AM Looks to be dripping from close to the front of the motor, not entirely. Getting underneath the car, looks as if it’s been dripping for a long long time, everything’s caked in oil, will have to dump a few cans of brake clean to continue diagnosis I guess. I can barely see the back of the AC Compressor with how much oil is caked onto it.
It's the classic M30 oil leak: the joint between the upper and lower timing covers, specifically the back corner. The gaskets only do a marginal job of sealing it and the recommendation is pack this joint with sealant. The geometry and angle of the motor forces the oil into this corner, then when it leaks (not if) it runs down the block and drips on the A/C compressor and eventually on the ground (driveway or garage floor).

Unless you plan on pulling main crank hub, unbolting the head, removing the timing covers and redoing this whole joint, learn to live with and get a metal/plastic drip pan (if it's not too bad that is).

It's a drag, I know but take solace that it's not happening to a freshly rebuilt motor after you've put countless hours into the whole project.
Like mine :evil: .
Mike W.
Posts: 24995
Joined: Feb 12, 2006 1:00 PM
Location: Covid 19 Life during Wartime

Re: Oil leak

Post by Mike W. »

Front crank seal is another common leak. But really you have to get it clean, at least where it might be leaking from, like from a pressure washer or DIY car wash, then see where it's coming from. Otherwise you're just guessing. But when cleaning with water do be careful of the spark plug wells, you don't want to fill them up with water. Otherwise the engine is fairly forgiving with respect to water but don't direct high pressure spray at anything electrical.
Topround
Posts: 27
Joined: Dec 31, 2020 11:50 AM
Location: New Jersey

Re: Oil leak

Post by Topround »

I got to take a better look at the leak, and yes, it does look like it is the timing cover.

It really does look like it’s leaking a lot, so maybe somewhere down the line this engine will be pulled for a refresh/rebuild.

That’s a shame.
Mike W.
Posts: 24995
Joined: Feb 12, 2006 1:00 PM
Location: Covid 19 Life during Wartime

Re: Oil leak

Post by Mike W. »

The lower timing cover is a PITA to pull, mostly because of the crank nut, but an oil leak is no reason to pull the engine if it's running well. Not everyone, but many have little to no oil consumption over 250K.
BMWCCA2
Posts: 3728
Joined: Feb 12, 2006 1:00 PM
Location: Central Virginia

Re: Oil leak

Post by BMWCCA2 »

Pulling the upper timing-case cover is not really a big deal. Do it while performing a valve adjustment. As I recall the hardest part was removing the thermostat housing when a bolt broke and had to be drilled out. I found it easier to remove the thermostat than to struggle with the upper case cover. I also removed the fan clutch, and the ignition rotor housing, too. Nothing all that difficult. New gasket strips and just be careful not to damage the head gasket. I packed the corners with Dirko and the coated the gaskets with Curil2. Mine has been perfectly dry for over a year.
Topround
Posts: 27
Joined: Dec 31, 2020 11:50 AM
Location: New Jersey

Re: Oil leak

Post by Topround »

I appreciate that, but this is only 110k miles and it’s leaking a lot. The car has to go to a body shop soon Anyway, for some reason the front of the drivers side frame rail is slightly crumpled. Needs either new metal or a little time on the frame machine, either way, the front end has to come apart, so I’d have decent access to it, and while I’m in there, a head gasket seems like good preventative maintenance doesn’t it? This car hasn’t moved since December, and even then, it leaked everything but it’s transmission and diff fluid, which is a miracle in itself. It had a coolant leak (prior mechanic incompetence, if you saw it you’d cringe as hard as I did), the valve cover gasket and apparently the timing cover was leaking, and I don’t quite know how the power steering system held any pressure at all, not to mention the vacuum leak that prevented the car from starting for three months.

Never underestimate what two guys, one night, a bottle of Jack and a harbor freight engine hoist can accomplish. Quality may not be up to BMW standards, but it’ll certainly be at least up to 80s UAW on a Friday afternoon standards
Topround
Posts: 27
Joined: Dec 31, 2020 11:50 AM
Location: New Jersey

Re: Oil leak

Post by Topround »

BMWCCA2 wrote: Apr 04, 2021 9:31 PM Pulling the upper timing-case cover is not really a big deal. Do it while performing a valve adjustment. As I recall the hardest part was removing the thermostat housing when a bolt broke and had to be drilled out. I found it easier to remove the thermostat than to struggle with the upper case cover. I also removed the fan clutch, and the ignition rotor housing, too. Nothing all that difficult. New gasket strips and just be careful not to damage the head gasket. I packed the corners with Dirko and the coated the gaskets with Curil2. Mine has been perfectly dry for over a year.

This is very good information, I already have the thermostat assembly off the engine, I struggled with the fan clutch already trying to replace the water pump, couldn’t figure out how to get it off, and just decided to leave it for the next guy, but I guess now I kind of have to figure it out. I was also going to replace the cap and rotor but I ran into a bit of a road block, namely the previous owner using a clamp to hold the distributor cap in place because he broke the top bolt, and him using multiple different type of fasteners for the distributor cap. Also, I’ve never adjusted valves in my life, but if I had to guess, I would say these are probably not within spec, this whole car has been a bit of a nightmare, mostly due to incompetent people working on it before. If this is going to be that much of a pain I’ll have someone else take a look at it, I’m not confident in my ability to not destroy this ever so rare M30 distributor, nor my ability to remove that broken bolt without causing more damage
Topround
Posts: 27
Joined: Dec 31, 2020 11:50 AM
Location: New Jersey

Re: Oil leak

Post by Topround »

BMWCCA2 wrote: Apr 04, 2021 9:31 PM Pulling the upper timing-case cover is not really a big deal. Do it while performing a valve adjustment. As I recall the hardest part was removing the thermostat housing when a bolt broke and had to be drilled out. I found it easier to remove the thermostat than to struggle with the upper case cover. I also removed the fan clutch, and the ignition rotor housing, too. Nothing all that difficult. New gasket strips and just be careful not to damage the head gasket. I packed the corners with Dirko and the coated the gaskets with Curil2. Mine has been perfectly dry for over a year.

This is very good information, I already have the thermostat assembly off the engine, I struggled with the fan clutch already trying to replace the water pump, couldn’t figure out how to get it off, and just decided to leave it for the next guy, but I guess now I kind of have to figure it out. I was also going to replace the cap and rotor but I ran into a bit of a road block, namely the previous owner using a clamp to hold the distributor cap in place because he broke the top bolt, and him using multiple different type of fasteners for the distributor cap. Also, I’ve never adjusted valves in my life, but if I had to guess, I would say these are probably not within spec, this whole car has been a bit of a nightmare, mostly due to incompetent people working on it before. If this is going to be that much of a pain I’ll have someone else take a look at it, I’m not confident in my ability to not destroy this ever so rare M30 distributor, nor my ability to remove that broken bolt without causing more damage
Topround
Posts: 27
Joined: Dec 31, 2020 11:50 AM
Location: New Jersey

Re: Oil leak

Post by Topround »

Ok so I need to replace the upper timing cover Anyway.

Does anyone know the part numbers for the gaskets and that seal?

Thanks

Nvm realoem was a huge help. Scored a new upper timing cover used on eBay, got new gaskets and the seal, and a new valve cover gasket just in case, and when that all shows up I’ll probably also clean and paint the valve cover while I’m installing the other shiny new stuff, thank you all for the input and advice
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