I have a C7 that started to smoke yesterday and looks like it pushed the coolant out of overflow. Temp. didn't go up much past normal, checked engine oil today and it is over full but not milky. Coolant recovery tank is empty. No moisture coming out exhaust. Sitting idling no smoke but put the power to it and it will smoke you out. Any Ideas? ED
An update on this problem on the C7 CAT. We took it to CAT dealer and found that a coolant had gotten into the air system through the compressor. Replaced compressor and cleaned out all of the lines & changed air dryer. They checked the head gasket and thought it "might" be leaking so replaced it and had head checked for cracks,none. Replaced injector sleeves and seals. Front cover was leaking so replaced gasket on that. SOOOO needless to say $8600 later our C7 is fixed. It runs well now though.
How many miles on the bus? All four in the fleet I was driving in were Blue Bird All American FEs and had the line between the compressor and air tank plumbed too small. Every few thousand miles the buses on routes with the worst hills would blow the air compressor head gasket. Signs were sudden overheating, loss of air pressure, and coolant spitting out of the dryer. It might be worth checking the diameter of your outlet pipe against what CAT says it should be.
It has 111000 miles on it. I will check the line to see what it has. Thanks.
Bwest, I could have done the repair myself but our shop is only one usable bay so I would have tied it up for a couple weeks and I also don't have enough knowledge about the CATs to do the job correctly. Plus lifting the head off!!UFF DAA