since i got this truck it has had over heating issues so i threw these parts into it, new double core radiator, new 180 degree fail safe t-stat, new ECT sensor, analog temp gauge, 18" E fan, fresh coolant,and new rad cap. i have replaced almost everything on this truck since i got it.

so it runs a heck of a lot better, and doesn't over heat some times, but most of the time it will stay pegged at 0 for a while then steadily climbs to 180, goes past that to 205 or 210 and then sits, slowly heating up... BUT if i stop the engine, then start it again, cools way down to 180...

its really driving me crazy, im trying to avoid having to rent a pressure tester and all that mess to test everything out.

oh yeah its not burning coolant but i do have a leak in one of the freeze plugs, the PO had gotten lazy on the passenger side freeze plug that sits behind the motor mount in the middle, he installed it kind of cockeyed. so it only leaks after the engine has cooled down.

 

Is it a older truck? After replacing all that stuff, is there a possibility that you have a large air pocket in the system?. Does it over heat while driving or while in traffic? Are the e-fans turning on at an appropriate time? The original fan shroud is an important part of the entire cooling design, are you routing air appropriately through the radiator?

Need more info please..

 

it over heats while sitting, i know it needs a 2nd fan, the fan really moves a LOT of air but i dont think its covering enough surface area of the huge radiator i shoehorned in there. stock fan shroud was removed long before i got the truck. whats the best way to burp the air out in these ford engines, on my chevys i always ran the engine with the radiator cap off.

 

If it is only doing it while sitting, then I would say that the size of the fan and the coverage, is what is causing it to over heat. Either add a fan or do something to direction the air through 100 percent of the radiator.

To get rid of air that may be trapped, you can try running it on different levels of ground. Or pulling a vacuum on the system and then refilling it. A lot of places that swap your coolant do this to replace it. They pull a vacuum to remove and then use the vacuum to replace it. They usually do this a couple times to get most of the coolant out.


GL

 

what does it mean if i hear water boiling in the top end of my motor after i shut the truck off? i heard and felt a loud CLUNK the other day, then the temp dropped a lot. never seen this happen before, i wonder if the water pump is damaged?

and what does small ammounts of vapor/smoke mean in my coolant? i hope it don't mean head gasket.