problem with over heating.

[GasGuzzler]

Gotta have a good seal at the cap to maintain the pressure required to raise the boiling point of the coolant.

[PunishedC10]

Well it seems to be better for now.
What about the clutch fan........am i right or wrong?
I have been told I shouldn't be able to spin it like that so I changed it out.

[PunishedC10]

It still seems to be doing fine for now. I've been driving it now so hope problem is solved.

[DigitalBoy0101]

Gotta have a good seal at the cap to maintain the pressure required to raise the boiling point of the coolant.

This is very correct. Pressurizing water greatly increases the amount of energy (heat) it can absorb before flashing to steam. The more energy (heat) it carries to the radiator, the more it can dissipate.

The principles of heat transfer were drilled into my head in the Navy heh.

Another way to raise the boiling temp of water is to add salt.......good for cooking, but a big no-no for engines. So pressurization it is.

I'm guessing both your fixes were steps in the right direction. The oval filler neck was definitely NOT good! It seems to be running now, so I would think you got it.

I'm gonna resurrect my Blazer some year, I might be asking you for help then!

My Avy is nice, but I still love that old Blazer. It was a good truck for me for several years, and I love the look as well. When I bring it back to life, my plan is to make it a trail truck. Lift with around a 40" tire, 6.0L/4L80E. Not sure what I'll do for axles, but the stockers will have to go. I read somewhere here that the T-case in my '89 is actually perfect for the 6.0L/80E swap, so I got lucky there.

But this thread is about your truck. Sorry for derailing it, and hope your problems are fixed