COOLANT/CAVITATION/RELATED QUESTIONS

[71 Highboy]

71 Highboy,

Wow 2 engines each 5 times!!!!

I wish there was an award I could send through Oilburners for kind of dedication to a old IDI! I would cut bait after the 5th time, just bought a nice running truck!

I am going to use your case study to remind members about how you have to hang in there and see it through. Once you do you will have a great truck!

Sorry for your plight, it should not be that hard!

Hats off to getting it done!

All the best

Tenacity! I was only trying to point to the cavitation issue at the top. Long story is after 29 yrs the old 6.9 was acting like head gaskets failed. Replaced them while the 7.3 went in and out a few time to fix various leaks. I did not deck the block, so the gaskets failed cuz of erosion at the fire rings. So the 6.9 went to get decked and bored, and the 7.3 went back in. I could never get the 7.3 to perform as well as the 6.9 after throwing bags of $ at it for NEW stanadyne injectors, new pump, etc. I get the 6.9 back as a short block, put it together with a nice cam and new lifters, pistons, bearings, oil pump, etc., and it's STILL pressurizing the cooling system from combustion. So that time it went complete to the machine shop cuz I thought I had a cracked head in an exhaust port, and they supplied the heads. It would hydrolock after shutting off. Let the water out the glow plug hole and it would run fine. That's when they found the pinhole in the cylinder wall. Not enough to let water into the basement, just enough to make ya wonder...

 

[cbmech]

Cavitation is the formation of bubbles in the coolant due to poor coolant and then the bubble imploding along the coolant side of the cylinder when it fires. It can eventually eat a hole all the way through the cylinder wall. It's always obvious on a wet sleeve engine when you pull the sleeve out.