Author Topic: gray sludge on oil dipstick?  (Read 11142 times)

Offline team39763

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gray sludge on oil dipstick?
« on: February 14, 2007, 04:30:00 pm »
I checked my oil a few minutes ago, and it had drops of clear water from top to bottom of the stick.  I'm assuming moisture built up on the knob at the top and dripped down(was very humid/foggy the last few days.  But does that explain the gray sludge at the bottom?  I think it kinda smelled like fuel, but I'm not sure (the whole truck smells like fuel).LOL.  If it's a coolant leak, can I get away with just changing my oil and finding the leak soon or do I need to pull the motor and inspect bearings and surfaces?  Truck is a 86 silverado with a cammed 350 , vicotor Jr, w/demon carb and longtube headers.  Plugs are most likely crap aswell as wires too.  Would that explain fuel in the oil?  I'm a little new to motors and stuff, but I'm trying to learn.  Any help or advice would be greatly appreciated.  Thanks.

Edited by: team39763 at: 2/14/07 6:13 pm

Offline GMCTed

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Re: gray sludge on oil dipstick?
« Reply #1 on: February 14, 2007, 06:35:00 pm »
are you sure it was a grey sludge and not a light tan color? if it`s tan that means you have water/coolant in your oil. one other way to check is to look under the oil filler cap on the valve cover to see if the same tan sludge is under there. you can also drain the oil and see if more of the same comes out. if you have water/coolant in the oil you most likely have an intake leak or a blown head gasket. i hope this helps,  Ted


Offline team39763

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Re: gray sludge on oil dipstick?
« Reply #2 on: February 14, 2007, 08:15:00 pm »
It may have been tan.  I'll have to check better tommarrow.  I did notice that I was missing some coolant.  I wasn't sure where it was going to.  I think it may be coming in from the intake, I saw some dried coolant on the seams.  Hopefully I can get that checked out in the morning.  Thanks.


Offline DnStClr

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Re: gray sludge on oil dipstick?
« Reply #3 on: February 14, 2007, 08:47:00 pm »
I don't think gas should ever be found in the oil, even with a gas leak, unless the carb is pouring so much gas into the intake that the piston rings can't seal it out of the combustion chamber. I'd hate to see the cylinder walls if that's goin on-
The discoloration of the oil is a sure sign of engine coolant finding it's way in there.
The coolant flows thru the engine in the water jacket of the engine, and the oil circulates by way of oil passages. They stay separate unless one of the systems gets plugged or overheats.  If the valve cover pvc valve or beather cap is plugged, pressure can easily build up inside the engine and cause the head gaskets to blow. When that happens, coolant can get by the blown gasket and go into the oil in the engine.  

Don St.Clair
Culleoka Tn

Don
87 Chevy Silverado

Offline team39763

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Re: gray sludge on oil dipstick?
« Reply #4 on: February 16, 2007, 06:40:00 pm »
I think my intake was put on using the wrong gasket.  I have ordered the correct gasket and will get it installed soon.  Then I'm going to see about checking the jets on my carb and put in the right size for my combo.  Thanks ya'll.


Offline VileZambonie

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Re: gray sludge on oil dipstick?
« Reply #5 on: February 16, 2007, 09:24:00 pm »
If you have a mechanical fuel pump, the diaphragm can leak into the crankcase which would explain your fuel smell and grey oil.


Just check the torque on your intake manifold and torque it in sequence.  

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Offline DnStClr

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Re: gray sludge on oil dipstick?
« Reply #6 on: February 20, 2007, 12:59:00 am »
Quote:
the diaphragm can leak into the crankcase

Oh man. I forgot about the pump. You're right again Vilezambonie

Don St.Clair
Culleoka Tn

Edited by: DnStClr at: 2/20/07 1:00 am
Don
87 Chevy Silverado

Offline team39763

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Re: gray sludge on oil dipstick?
« Reply #7 on: February 22, 2007, 04:25:00 pm »
I found out that the intake manifold was put on using an incorrect gasket.  The PVC valve was completely plugged with this gunk and oil, so it'll be replaced.  I'm also going to replace my fuel pump and jet down my carb a little.  Hopefully those changes will solve the problem.  Thanks ya'll.