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1992 Silverado 5.7L V8 Leaking Coolant

6K views 8 replies 4 participants last post by  Allistah 
#1 ·
Hey all --

I have a 1992 Silverado 5.7L V8 that is leaking coolant. I looked under the front of the truck to see if I can see where it is coming from and it looks like it's the lower radiator hose going from the radiator to the engine. I ran the truck and the leak seemed to stop. I cleaned the host with a rag and will wait until morning to see if I can see exactly where it is coming from. I'm hoping it's the hose.. If it is not the hose I'll have to go another direction.

Now my question is this.. Is that lower hose easy to change? I'm assuming I will have to drain out all of the coolant to replace the hose? Since it's an older truck, I'm thinking I might as well replace the top hose as well while I'm at it. Does that sound like a good thing to do?

Is there anything I need to watch out for while doing this?

Any help or pointers would be appreciated. Thanks!
 
#3 ·
Great, thanks for the info.. How do I drain the coolant without just letting it run all over the ground? Is there a drain or something I can open to drain it?

I'm guessing I'll need to jack the truck up to do this change and it will need to be done from underneath?
 
#5 ·
So yesterday I took off that heat shield thing and wiped the hose down and was going to go check in in the morning (now). I go out there and now it's not leaking anymore. Ugh... It was pretty warm here yesterday so I'm thinking once the temp gets up there again it will start to leak maybe. Maybe since it's cool things have shrunk and stopped the tiny leak. I just wanted to verify it was coming from the hose before I go and spend money on new hoses.

Any other advice on this one?
 
#6 ·
Most likely it's the water pump, very common, seen many times person feels it's the lower hose all to come back and say I changed hose and it still leaks. Look at the water pump from under the truck there is a small hole probably the size of a BB or slightly larger called a weep hole. Look for staining if you see it you need a new water pump. If it were my truck I'd upgrade upper and lower radiator hoses and thermostat while doing the wp at same time.

Btw don't forget permatex gasket maker to seal thermostat housing. Don't buy premixed coolant either you are paying twice as much for half water. Regarding draining the system I'd pull the lower hose let it drain into a bucket. The peacock drains don't always reseal nice once disturbed. Flush out top of radiator till bottom comes out clear. Also buy NEW water pump and make sure gasket is included skip the Remanned they don't last. Hope this helps you.
 
#7 ·
I had talked to a family friend that works at a Chevy dealer (for many years) and he described the same thing about the weep hole. He said that they leak, then stop, then leak, etc.. He said if it's a hose, the leak won't typically stop so he is betting on the water pump as well. I think you're right though.. I don't want to screw around with the hoses and thermostat either later on and I'd rather replace all of them at the same time to get it done and over with.

I'm actually going to go have our friend replace it. I don't have enough experience to do it myself and I wouldn't mind learning but I don't have the time as I need it to be fixed today. So he is going to do it for me and I'll know that it's getting done right by a dealer mechanic.

Thanks so much for taking the time to post - and confirming what I was told. I really appreciate it.
 
#9 ·
Thanks for the confirmation. I think those hoses and thermostat are pretty cheap - so why wouldn't you change them out if you already have it apart? Plus I noticed that the radiator cap is also leaking (used some soapy water to see it) so I'll have to replace that as well.

This truck sat for 14+ years without a lot of use. The power steering pump was replaced, the AC compressor was replaced and updgraded to 134a from R12, the alternator was replaced, and now the water pump. I don't think theres anything else to replace. LOL

Thanks again for the posts and help. I really appreciate it.
 
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