hi everyone new to the group. i was wondering pinions i guess. my zr2 loses a lot of coolant when i drive every time after 20 min or so it begins to run hot. i believe the leak is radiator or at least where i will start. i was going to order a new on and some are just radiator and others have dual fans. the one i have now has one big fan. do the others replace the one big fan with two or do i somehow use all three. does anyone have any wisdom here done before. and are the two fans better. also note i have checked antifreeze not in oil or anywhere i can find. i’m thinking radiator leaking. either way i believe it’s original won’t hurt and gonna replace hoses too. any advice will be appreciated. ghanks

 

I'm pretty sure all the Blazers came with a fan driven by the serpentine belt. In stock configuration the cooling system should be fine for almost all applications. The exceptions would be if you are driving in extreme conditions or towing something.

Before throwing parts at it, I'd rent/borrow a cooling system pressure tester from an auto parts store. With it, you can pressurize the cooling system and find out where the coolant is leaking. Then you only have to replace the failed part. If you are lucky, you might only have a loose hose clamp!

There is one possible failure mechanism that could be be trouble with the cooling systems on our trucks, a leaking lower intake manifold (LIM) gasket. When these fail, coolant will leak directly into the lifter valley of the motor, mix with the oil, and if enough coolant enters, all the bearings of the motor can be ruined. The check for this is to see what your engine oil looks like. Does it have any coolant in it or is is a light chocolate milk color? If so, you have an internal leak. Another source of an internal leak can be a head gasket but I have not heard of this being at all common.

If you want to upgrade your cooling system, there are people who have found replacement electric fans and there are aftermarket all aluminum radiators that come with electric fans. These can be a good upgrade.

 

@christine_208 the oil isn’t milky or anything i’m gonna get pressure tester i guess and hopefully find leak hopefully just a hose. thanks for the advice will update once i run pressure test

 

Be sure to report back with what you find.