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Need help with a cooling issue

Old 08-08-2017, 11:45 PM
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Default Need help with a cooling issue

What's up guys I haven't posted much so I'm not sure where to ask this but I'm having a issue with my cooling system. Little back ground on the truck I have 94 full size blazer and here is what i have done I just installed the engine from a rebiuld I did a full rebiuld pistons cam valves the whole engine on top of that I replaced external engine parts like cooling sensor water pump egr plugs wires oil lines 90 percent of the components in the engine bay have been replaced or rebiult. There is less than 600 miles on the rebiuld.
now when I first installed the engine I had a hard time with the timing wich made it over heat really fast so the first initial cam break in was a pain. After that I still had issues with overheating so I replaced the radiator then fan clutch hoses etc and with each part it has got better but I'm still a little leery of the temp. I live in phoenix az wich on a cold summer day is 110 degrees. Out on the freeway the temp will stay at 208 210 degrees and at a stop light it will run 210 213 range. Now when I put the engine together I installed a 195 degree t stat and I had a really hard time getting the air out of the system. What is making me nervous is that the temp fluctuates so much and If I stop some where for 10 min and come back to start it the engine has a hard time starting like it is overheating from heat wash. I put a aftermarket gage in to get more accurate readings. Now i can tell when the t stat is fully opened with this gage because the temp will go to 215 220 then back down to 195 once open then goes up from there.
is my t stat too hot for where I am?
do I have air in the system still?
is the gage making me think I have a problem?
the truck also has 9 inches total suspension and body lift so the fan dosent exactly sit square with the radiator.
Old 08-09-2017, 06:39 PM
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i had a old k5 blazer with a body lift and cracked fan shroud and never had any issues. if your running a mechanical fan you can get a heavy cooling clutch for it. bought one of those years ago for a old blazer i had that used to overheat when going slow out in the woods. never really had any problems with 80s or 90s trucks trapping air in the cooling system either.

another simple thing you can do if your radiator is a bit older get some compressed air or a garden hose and blow out the front of the ac condenser and radiator to get all the bugs, dust and cotton woods out of there. i blew mine out a few months ago, radiator was like 5 years old and clouded up the back yard with all the dust

so... good fan clutch, clean radiator, good fan shroud. just a start
Old 08-10-2017, 05:16 AM
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Thanks some new ideas the radiator is brand new but I didn't think about the other stuff being plugged up. I also have gaps in the shroud from the body lift may be part of the issue
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