Coolant loss and I'm at a loss to where it's going

[georgia mike]

I just bought my M1008 last weekend. When I test drove it, there was a lot of white smoke from the exhaust. It wasn't there under normal driving, just under a heavy load (like when the throttle was pressed more than half way). I figured that since the truck had been sitting a while that maybe it was accumulated moisture in the fuel. Since it was only at heavy throttle, and seemed to get better during the test drive, I rolled the dice, and bought the truck.

Before heading out I noticed that the radiator overflow tank was empty. We topped it off and I was on my way. The drive home was roughly 250 miles, and I lost no coolant at all. The overflow tank was still full when I got home. The smoke had all but disappeared and hasn't returned at the level it was during the test drive, just an occasional whiff of it from time to time, and a bit during warm-up.

I've been daily driving the truck now all week and yesterday when I was changing the oil, I noticed the overflow was empty again I can't see any coolant leaks anywhere, and no traces of where it could be leaking while driving. There was no coolant in the oil when i drained it. What are the chances that I have a bad head gasket?

 

[doghead]

Do you have a hole in your coolant overflow tank?

Probably a bad head and or gasket.

 

[Goose2448]

I'm gonna assume that its a bad head gasket, maybe just a small hole in one spot. Have you checked your trans fluid? I had a trans cooler go bad once and ended up with a whole bunch of coolant in my trans......

 

[georgia mike]

Yes, I also checked the trans fluid as well when searching for where the coolant was going. I've been reading up (read: scaring myself) about other possibilities, such as the cracked head or cracks in a cylinder wall. Man, I really don't want to have to buy another engine! I'm really hoping that it is in fact a simple head gasket job. I can handle that cheaply enough.

Where should I focus my attention when inspecting the heads once I remove them? I remember now that my wife did say when she was behind me on the way home from buying it that even though the smoke had subsided considerably, there would still be a puff from the left side, but only from time to time. I'm assuming it would happen under heavy throttle.

 

[Tow4]

White smoke is moisture in the exhaust. If it doesn't go away after the truck warms up you have head gasket problem or cracked head.

 

[ralbelt]

Remove head and have it pressure checked, if its cracked it will show up. If its good might as well have the valves and seats cleaned up. Just as a precaution might as well pull the other side and do the same.

 

[llong66]

I had a cracked head on mine when I bought it, once I got the head off, it was no problem to see, cracked right between the valves.

 

[georgia mike]

So I take it that blown head gaskets and cracked heads are common ailments with these engines?

 

[Ken_86gt]

Not really, but after 25+ years you are going to have head gasket and other failures.