A little backround first. 1994 jeep grand cherokee 5.2. I bought it from a friend who had it sitting in his yard for a few years. Changed all the fluids and it ran great but burned some oil due to needing valve stem seals. I changed em out and did the plenum gasket as they are known problems. Did an oil change with some marvel mystery oil thrown in to help get rid of any deposits from burning oil. A few hundred miles later it started haunting for idle when warm and slightly overheating. We found bad leaks at the exhaust manifolds and suspect thats the problem. For good measure we did a compression, leak down and coolant exhaust test. No head gasket problem. All cylinders were 125-130 psi. As there were a few other things we wanted to work on, we decided pulling the engine would be easier. Noticed the pan was leaking pretty good so i pulled it off and there was a ton of sludge and sand like grit. We thinned some of the sludge/grit mixture and there was no signs of metal. We took the cover off the oil pump and no scoring. Also spun the engine by hand and as far as we could tell, looking from the crank side of the bores, no scoring there either. The amount of grit has me concerned though.
I was thinking of doing a 50/50 oil kero mix, running it for about 2 minutes, then drain. regular oil for a few hours then another change. Good idea, bad idea or anyone have another idea?
I was thinking of doing a 50/50 oil kero mix, running it for about 2 minutes, then drain. regular oil for a few hours then another change. Good idea, bad idea or anyone have another idea?