Newbie to the forum, hopefully I'm in the right place.

My 2000 Blazer started leaking coolant so I took her in to get checked up and she failed a combustion leak test (or she nailed it?). How long can I reasonably go before I find myself on the wrong end of a tow truck? I'm asking because I'm considering selling her to Carmax and need time to find another car. Any other advice is appreciated.

Thanks!

 

"... failed a combustion leak test" please explain how this was determined, ie what tests were performed. It's very common for the intake manifold gaskets to leak coolant on these engines. They can leak internally, externally, or both. It's not impossible, but it is extremely rare for coolant to leak into an intake port.

 

Hi Captain, thanks for the reply. It was one of those blue liquid tube tests which turned yellow. That was the only test performed as he said he doesn't do that kind of work. He thinks the water leak might be from the water pump and he said as long as I watch the oil and engine temp, I should be okay for a little bit. But since he doesn't do the work, I thought I'd double check with people with specific knowledge of Blazers.

 

Ahh.. you mean combustion gases in coolant system. Mostly used to detect head gasket failure.

 

Hmmm, if he's suggesting a faulty head gasket, I'd get a second opinion. Head gasket failure on a 4.3L is almost unheard of. Usually they're replaced due to misdiagnosis of a leaking intake manifold gasket. IF the head gasket has failed, and leaking internally as it sounds like he's suggesting, there will most certainly be other symptoms such as an over-pressurized cooling system which can lead to blown hoses, radiator, heater core, etc etc. Get a second opinion on the head gasket and a cooling system pressure test.

 

What symptoms do you have, i.e why did you take it there in the first place.

I find those combustion leak tests accurate as long as coolant did not introduced in the tester. This is a common problem as you need to put the chamber under vacuum while it is on the radiator.

Do you have milky oil? Excessive steam out of tailpipe?

 

She's started leaking coolant near the radiator which is why I took her in.

I don't have the other symptoms of head gasket failure, no milky oil, no excessive steam, which is why I didn't bother to have that tested before.

She's had an array of coolant related problems for a while now which I can get into if it's important.

As I mentioned, my mechanic said he didn't do that type of work and I can get a second opinion from the guy he recommends. But I think she's beyond my ability to take care of her without becoming a money pit. For giggles, I called the dealer who quoted $2k minimum for head gasket replacement.

Right now, I'm just hoping she can hang on a little longer until I can find a better situation for the both of us.

 

I might dismiss the diagnosis until/if some symptoms show up. To replace a head gasket because fluid changed colors just seems silly to me.

It is also concerning that a guy who does not usually do that type of work has made a call about something he does not do.

These engines are pretty dang strong, while I have seen a few needing replacement and head gaskets, it is not very common. Though, as you can see I am new to this forum and others who have owned these rigs longer may have different things to say. I am just speaking as a tech, and there are a bunch of these things on the road and I do very little heavy line with the engine in these things, just the intake gasket.

During your coolant issues, if you let it overheat big time then it does raise some concern to potential head gasket issues, but again you have no other symptoms. I would drive the **** out of it and see if anything shows up.