Yes, but before you replace the radiator you may want to do the Dexcool flush. This was very common on GM cars of that time. The procedure was to mix some wood acid with water and poured into the cooling system and run the engine for a little while to flush the Dexcool out of the cooling passages. I did this with my son's Tahoe which was completely plugged up with Dexcool. After you do that replace the radiator and any hose that is over 10 years old. Of course install a new inline thermostat as well.

 

Thank you all for your knowledge and assistance!!!

I was able to install new head gaskets and reassemble(few more pics below)
IT STARTED!!!
Lot less white smoke than when I started the job...Got excited...shut it down... then I realized.....
I still need to replace radiator, thermostat, and flush coolant system...

Are there any other suggestions and the exact order ?
My first mind is add coolant and start driving, though seems there is a bit more work to go...

What's next before I put it in (D)rive ?





did not seem to be the exact part, i added ultra gray to the gap :|

skipped shroud for start up test...

 

@logicmike44 Great feeling when she starts right eh. I would do the flush a couple to times, change out the thermostat,but leave everything else, put AF in and drive for about 500 miles. Then change the oil and filter, then do all your hoses and rad. But it is personal, you can do the complete cooling system overhaul 1st. But you still want the short oil change interval.

 

there is normally a small gap on the water pipe at lower intake(the pipe in your pic), that's why new O ring should be used on the inserted tip. However, gap in your pic is more than expected....Pipe bent?

 

...time to test. Added coolant.
Heat warm, but not hot when adding coolant and bleeding before test drive.

Idled at 210f consistently for 15+ minutes.

Short trip around block and 1st stop light temp rose to 218, then back to 210, second stop light longer, temp up to 228-230. Pulled over and shut off.

Hissing and white smoke under hood. Noticed leak from pipe inlet.(photo)

Luckily it released pressure from inlet pipe and not head gasket...

All hoses were warm/hot except lower radiator hose. Top engine facing radiator surface warm, bottom cool.

Belt routed correctly

No more bubbling overflow, no more white smoke from tailpipe...

...but still high pressure build-up...??? From where/what part....???

Guess radiator flush or replacement next

Will remove, replace O-ring and reseat... Still need to locate pressure source.


.

 

@logicmike44 Did you change the thermostat the old one is very likely compromised from the overheat, and not opening. With the whiteish oem style thermostat and that leak I would expect those temps

 

X2. replace the thermostat (seriously get the inline thermostat at the top of the DII section), fix the leaking part, refill with coolant, bleed properly several times and see how it does after.

 

Just commenting to reinforce the inline thermostat. Cooler temps and less flow restriction help immensely.

 

Still pressure under higher load.
changed thermostat, was able to bleed and get heat.

210 Idle 662 rpm 9% Load
208 Rev'd to 2175 rpm with heat on 21% Load
208 Rev'd to 2421 rpm with heat on 22% Load
Drive around block again, overheated again, blew top hose at the "T"

Radiator cool, top hose hot.
Removed top radiator hose and found gritty residue, water flowed well when poured through top hose to the bottom.

Still building pressure under higher than idle load...
TBH, Heater core, or...???


inside top radiator hose

idle

rev'd to 2421rpm with heat on

rev'd to 2175 rpm with heat on

 

Maybe your block is cracked