NVW
Well-Known Member
My 95 K3500 was rebuilt 3 years ago, after about each and every month I would have to add a bit of coolant. There was a slight vapor under the oil fill cap. Then the WP gasket let go and I fixed that thinking my problem was fixed. No go. I thought maybe the head studs had a poor seal but I could put 16 psi to the cooling system with my Mighty Vac and 24 hrs later it would be at 15 psi.
Last summer I used pure water and the leak stopped, I know antifreeze will leak where water won't, then I switched back to a mixture and the coolant loss reappeared.
This winter I was using RO water from town which uses Chloramine instead of Chlorine for water treatment. Some say it eats chrome fixtures. Anyway it has since developed an extreme dump of coolant into the oil.
I had suspected the head studs but am at a loss on the pressure tests, I even did one with the engine at operating temp and had the same results.
I'm thinking there is a crack in a head intake runner/coolant passage, or the head studs that let coolant through under expansion due to heat. The Chloramine may have eaten out the Locktite on the threads.
Oh, 4 cylinders compression tests at 380+ psi and 4 test at 400+. Not a head gasket IMO. No hard coolant upper hose.
BTW the engine is on it's way out for an inspection and bearings.
Last summer I used pure water and the leak stopped, I know antifreeze will leak where water won't, then I switched back to a mixture and the coolant loss reappeared.
This winter I was using RO water from town which uses Chloramine instead of Chlorine for water treatment. Some say it eats chrome fixtures. Anyway it has since developed an extreme dump of coolant into the oil.
I had suspected the head studs but am at a loss on the pressure tests, I even did one with the engine at operating temp and had the same results.
I'm thinking there is a crack in a head intake runner/coolant passage, or the head studs that let coolant through under expansion due to heat. The Chloramine may have eaten out the Locktite on the threads.
Oh, 4 cylinders compression tests at 380+ psi and 4 test at 400+. Not a head gasket IMO. No hard coolant upper hose.
BTW the engine is on it's way out for an inspection and bearings.
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