If your heater core is leaking, you will not see it under the hood. It will wet the carpet on the passenger side under the heater. If you switch on the defrosters it may blow steam.

 

I meant Anti-freeze my bad...Sorry about that. I never put just water in unless its an emerg. Yep, most everything is org on the eng except for the A/C compressor change in 2002, New battery every like 5 yrs, new alt (Both at the same time like 3 months ago) new neg bat cable same as bat and alt. New fan clucth replaced twice last time about 3 yrs ago, new Rad and hoses around the same time. Like everything around the engine but no gaskets, head work etc..thats all org with 106K or it. I will try and get a sneak peek around the intake it is hard to look around there with everything on engines now days. But I have mirrors etc..But will look. I assume the blazer has to be running to see the leaks? or will there be a tall tale sigh of a leak? Like rust color etc.
Heater core is good, water sound until it warms up the it goes away, good heat no wet carpet.

Once again thanks for all the help.

 

If the heater gurgles it is because it isn't full of coolant. Mine used to do that before it started leaking big time. I replaced it this week. When I pulled the core out of the housing it was literally dripping coolant.

 

Does not have to be running to locate leaks, but a pressure tester would make it easier to locate them. If you're using Dexcool coolant, the tell tale will be orange or white tint. If using ethylene glycol, it will be green. Adding some UV dye to the coolant and using a black light locates leaks in a heartbeat!

 

Could be right on the heater core, When it makes that sound is when I know I'm low of fuild. And if its a little leak waiting to become a large leak that could be it. Will have to check it out..

Thanks All.

 

At 1st I thought it might be the intake gasket, but after further stariing at the problem I notice a leak on the upper intake manifold (Coolant, green leaking on the right side of it, not a lot but leaking) I did not notice any other leaks. I didn't know that coolant went that far into the engine. Or am I right and another monster is in the closet waiting to jump me? Do me that would mean coolant in the engine oil but its not there, oil is fine..So my leak is in between the throttle body and upper intake manifold. Is there a easy way to get the upper intake off?

Thanks.

 

Could be a heater hose or the lower intake manifold gasket is leaking. The gasket may or may not leak coolant into the oil, it depends where the gasket is bad. If you wait too long to repair it, the gasket will deteriorate and coolant will get into the oil. If you haven't done intake gaskets before, plan on the good part of a day to do it. Felpro gasket part # MS98002T. 2000 requires Dexcool, (orange) coolant. Make sure you completely flush all green coolant out of the entire cooling system, (radiator, heater core, engine block, hoses). Mixing the 2 coolants, along with not flushing often enough, will acellerate gasket failure.

 

when i had mine done,lower intake gasket on my 2000 chevy blazer i went with the green coolant,it was just my prefrence,since it leaked out all the dex cool coolant i just went with the green.But i did go with the felpro MS98002T gasket set...