Oil Leak Diagnosis

[gnick]

Hello Everyone,

I bought an M1009 a few weeks back and have been slowly working through it. Last weekend I did the oil change and fuel filter change. While under the hood following the fuel filter bleeding process I noticed some oil on the passenger side header. It looks like it could be from the valve cover. After some research here I've found that the valve cover seals are a common issue as well as clogged CDR's, but before I started to tear into it I wanted to run it by some experts to see their thoughts. Please have a look.

 

[Al Harvey]

I'd lean towards valve cover gasket leaking.

 

[Matt65]

Try tightening first... Then if still leak, gasket.

 

[Assel]

do drips fall to the ground? my driver side head looks almost the same, but I never had to fill up any oil ..since I do the oil change regulary... but Id say its 95% the gasket

 

[gnick]

do drips fall to the ground? my driver side head looks almost the same, but I never had to fill up any oil ..since I do the oil change regulary... but Id say its 95% the gasket

I'm not noticing any drips to the ground. The underside of the bell housing does have some oil on it, but I never see any leaks on the ground. i just did the oil change so I dont know whether or not I'm losing any oil anywhere - although It was low when i got it from the PO. It was also really really dirty so i assume he just didnt change it often.

Thanks for the advice though guys - i'll try to torque the valve cover gasket to spec and see if that helps out.

 

[welpro222]

Try what Matt65 says, try to tighten the bolts first. If you feel you want to reseal the valve covers, only use RTV sealant. Make sure you triple clean the surfaces with break cleaner and apply a good 1/4" thick bead of RTV and then let it dry for 24 hours before running.

 

[welpro222]

Oil leaks are generally hard to find because our engines are greasy to begin with. I had a leak that coated my starter and I believed it was my valve cover also but it turned out to be my lift pump gasket.

 

[cpf240]

Two things:

1) A faulty CDR can lead to over-pressure in the crankcase, leading to leaks - though these usually show up at the rear main seal, so I doubt it would be casing the valve covers to leak. Some say replace the CDR, others say wash it in solvent and reuse.
2) Oil at the weep hole at the bottom of the bell housing can also be from a leak at the IP - the diesel washes everything down the drain and it comes out that point - the common spot is the throttle shaft seals, though the fuel supply and the injector lines are all right there as well.

 

[Barrman]

Just a dirty head and header without drips is something that can stay or get fixed. Depending on your level of OCD. If it is OCD, check the level regularly and normally it won't get any worse. However, if your OCD is actually CDO because that is the proper order. Then you better pull the intake, remove the injector lines and get some RTV in there.

3 of my 6.2 engines have at least one head dirty like that. They are still getting 5,000 miles to a quart of oil so I don't worry about it.

 

[gnick]

Just a dirty head and header without drips is something that can stay or get fixed. Depending on your level of OCD. If it is OCD, check the level regularly and normally it won't get any worse. However, if your OCD is actually CDO because that is the proper order. Then you better pull the intake, remove the injector lines and get some RTV in there.

3 of my 6.2 engines have at least one head dirty like that. They are still getting 5,000 miles to a quart of oil so I don't worry about it.

i appreciate the help guys. Nice to hear that it probably isn't a crisis. I'll keep an eye on it. For now I have a good running/driving M1009 that im pretty happy with. I'll working on the doghead mod this weekend and trying to clean up the electrical fiasco under the dash from the previous owner.

 

[dstang97]

Oil leaks are generally hard to find because our engines are greasy to begin with. I had a leak that coated my starter and I believed it was my valve cover also but it turned out to be my lift pump gasket.

I believe mine is leaking from there also. That or the turbo

 

[tourus]

if it is a leak and not to awful bad drive it a while let the oil cover the under side as it is real good under coating. drive on a few dirt roads on a dry hot day a few times then fix it makes the under side last longer. it will amaze you were the spaying oil will go. just a thought.

 

[welpro222]

Yeah no kidding, i had my k20 leak from the tranny to the transfer case, then out the rear seal and vent. It coated my driveshaft, axle, and tailgate.

 

[cucvrus]

They are still getting 5,000 miles to a quart of oil so I don't worry about it.
Wow 5,000 miles to a quart of oil. I change my oil every 2,000 miles. I always did on these older vehicles. It is cheap insurance to know that I always have clean oil. I don't waste the oil I burn it in the waste oil burner for heat in the work shop. I have a 2014 Silverado with 10 K on it. I only changed the oil once. I only change it when the truck tells me to. It seems to work this is the 3rd new truck that has the oil life system in it. But I never went over 2,000 miles on an older engine. Oil change is still the cheapest repair you can make. I use 15 40 Rotella T year round. I have engines with over 200,K on them and they are still cast iron colored on the inside. Some I work on I scrap the valve covers out with a putty knife. If it works for you keep doing it. I am a bit OCD about oil leaks and oil changes.