I fixed the block on my 89 4.3 Liter

My dad passed a few years ago and left me a 1989 S-10 Tahoo with the 4.3 Liter engine. Well, I had it about two year and it blew a head gasket. I had that fixed and redid the valves. Now a few weeks ago it started burning antifreeze and shooting steam out of the exhaust. I took it to a friend who looked at it and felt I either had a cracked block or the gasket is screwed again.

He tried putting some "stop leak' in the radiator and LOW AND BEHOND it has fixed it. Okay, it has almost 143,000 miles on it and I don't expect a lot but if I can only use it occasionally to haul stuff and maybe a short trip, I am fine.

Anyone else have a similiar story?

Stop Leak plugs up everything,including your rad and heater core.

Might do it. I guess time will tell. I just don't see getting a new block right now.


Stop Leak plugs up everything,including your rad and heater core.

I talked to my friend about that and he said he backwashed the radiator and heater core iwth fresh water. That should not be a problem but I do need to get a low pressure radiator cap now.


Stop Leak plugs up everything,including your rad and heater core.

lol doesnt matter, your heater core will plug, your radiator will plug, you can sometimes save the core with a flush, but the radiator will be doomed

Rads are 30 bux at the bone yard, so that's peanuts compaired to replacing the motor.

I'd be more worried about the heater core, since it's such a big job to replace.

Anyone else have a similiar story?

Yep, My 93 had a similar problem, burning antifreeze, really stinky, piss poor gas mileage, but it had a persistant antifreeze leak just behind the A/C pump..Changed the freeze plug and it still leaked...got tired of it all and dumped a tube of "Alumina seal" in it. Leak quit, performance got better and the stink started to ease up although it never has quite gone away yet.

I did believe that I had a bad head gasket until the symptoms didn't match up..Turns out it was the lower intake manifold gaskets.

So far so good. I went and bought a low pressure rad. cap today and hopefully this will keep the pressure down and keep the stop leak from blowing out. will keep you posted...151,000+ miles and counting

So far so good. I went and bought a low pressure rad. cap today and hopefully this will keep the pressure down and keep the stop leak from blowing out. will keep you posted...151,000+ miles and counting

I used "Bar's Stop Leak". Leak stopped. After filling up rad to top the leak started again until level dropped to few inches below cap. So leave level 2-3" below pressure cap. Don't flush it out or you lose leak seal.

Sounds like a plan! Thanks a bunch!



I used "Bar's Stop Leak". Leak stopped. After filling up rad to top the leak started again until level dropped to few inches below cap. So leave level 2-3" below pressure cap. Don't flush it out or you lose leak seal.