Thick Oil Sludge under Valve Cover

[aushole]

Ok, heres the deal with my wonderful rig! At 3 am the other morning, I decided i'd take a trip to maccas for a midnight snack., About a K down the road she over heated and stopped dead. By 4:30am the RAA had towed me home and I left me with the news I had a crook welsh plug.

Drove it to the mechanics for the welsh plugs and he informed me the head gasket was cooked, so I agreed to getting him to fix it all up when he again calls me with a problem.

When his apprentice took the valve cover off, there was an excessive buildup of sludge around the valve springs and push rods. Mechanic said it was by far the worst he has ever seen. The valve springs were hidden by a very thick grease like version of oil.

What are the chances of the rest of the motor being OK? before it died the jeep had more power and go than my XR6 falcon. Also, it would \randomly oveheat sometimes, would this be a contributing or the reason why? Any Advice is appreciated.

Sorry, cant get photos as i forgot to take the camera when i went to have a look at the workshop.

[geroxj]

the sludge your talking about sounds like water in the oil and then heated greatly in the rocker cover it has happened to every car/engine i have ever known to have blown a head gasket. If this is the case worst cas senario is a complete engine rebuild which can be quite costly, Sorry to be the bearer of bad news but you are not and will not be the last to have this problem i myself am rebuilding a motor atm after the head gasket went hope we can see the xj back on the road soon and happy jeeping

[whollsee]

Can also be due to short runs in colder weather when the donk doesn't get to optimal running temp. Has happened to me occasionally in winter. Definitely not a head gasket in my case anyway.

[Deezelweazel]

HOHO, worthy comrades hold your horses!
Before you can state such remote diagnosis you have to know the colour and the consistence of the sludge.
I agree that the yellowish goo can be extreme cold weather or short distance driving or in extreme a blown head gasket, but water in oil turns oil in the pan into a brown sauce.
If the sludge is black- it shows an extreme neglected engine or neglected oil changes, or to play the worst case scenario a non appropriate oil.

So what is the colour of your goo?

[bruggz351]

Originally Posted by Deezelweazel

HOHO, worthy comrades hold your horses!
Before you can state such remote diagnosis you have to know the colour and the consistence of the sludge.
I agree that the yellowish goo can be extreme cold weather or short distance driving or in extreme a blown head gasket, but water in oil turns oil in the pan into a brown sauce.
If the sludge is black- it shows an extreme neglected engine or neglected oil changes, or to play the worst case scenario a non appropriate oil.

So what is the colour of your goo?

This has been my experience. When I first started dating my wife, I did a oil change on her hatch back and only got about 2.5 litres out of it of thick black sludge. Took the valve cover off and couldn't even see any cams or rocker gear as the sludge had built up into the shape of the valve cover....

[aushole]

The goo is black. My Mechanic said it was from lack of oil changes by previous owner, turns out that checking the oil looks good on the dipstick when i got it wasn't a sign the engine had received a decent and regular oil change.

Costing me $1500 to have the top end done including a complete ovehaul ofthe head (Valve grind etc..), mechanic seems worried about the buildup of crap as it is down by the lifters etc, but i'm not wanting to do a full recon of the engine..

What do you think my chances of having bigger or more problems after he's got it all back together? i'd consider running soime engine flush / diesel through it but he said it's probably result in clogging the iol pickup.

[Deezelweazel]

Avoid additives and diesel in the engine. Bearing are very sensitive to it. Instead of using miracle fluids you can use Synthetic oils. Within a couple of 1000miles your engine will be clean, extremely- that's for sure. Only disadvantage of syns are the extreme cleanup will dissolve every dirt accumulation. That means if you have a leak which is covered by dirt the engine will start to leak- so you may have to reseal it.