Coolant loss

I did a search on this under blown head gasket and coolant loss with no luck. I apologize in advance if this has already been discussed.

'92 Jimmy with 4.3L. I have about 138,500 on the truck. It runs great at all speeds and idles fine. My problem is a coolant loss. I will fill up the over flow tank to the cold minimum level and four or five days later it is empty. I checked the radiator and it is full to the brim. I have checked for radiator leaks and hose leaks with no luck. Everything is dry as a bone. No cooland smell. The oil looks good and the exhaust seems normal...no unusual smell or smoke. Do you think I am headed for a head gasket replacement? If so can I keep driving the truck locally for a while or should I get it to a shop right away. If it is the head gasket do you all have any ideas on the cost to replace it? Any other thoughts or ideas beside the head gasket?

Any help/direction you all can give me is very much appreciated.

Charlie M.
Dallas, Tx

Do an oil change and check it. The gasket leak could be on the back and it's a slow leak, so what happens is that it spits out a little at a time onto the hot engine and burns up before you can smell it. Also check the water pump weep hole.

rlith, thanks for the reply. I recently changed the oil and it looked good. No evidence at all of coolant. I am going to get it up to operating temp and really give it a good look over the weekend. I will check out the weep hole on the water pump and see if I can get a better look at the back of the engine. If that green coolant is coming out there should be some evidence even if it is evaporating right away. I will let the forum know if I find anything. Thanks again.

Charlie M.
Dallas

If you don't find the leak on the outside, it can still minorly leak on the inside without dumping into the oil.

did you end up changing the head gasket? i am in a similar position, my coolant leaked out - oil was not high nor was there any exhaust smoke visible (at night driving 90mph who knows if i would have seen it). and one plug was heavily soiled and compression was way too low.
think i'll try to change it tomorrow...ugh.

Greg, my problem ended up being the radiator. It was ready to crap out so I replaced it and the coolant loss went away. I could not find a leak at idle. Good luck with your coolant loss problem. Let us know how it works out.