Hi all,

Firstly ive never been happy with my cars temperature antics since putting the 5.7 in, its been managable but even with both fans running it still hovers on the hot side if im stuck in traffic etc, but its always fine when im driving around

Today i was out in the car and was in slow moving traffic but even with the fans going the temp wouldnt come back down from 250 according to my digital temp gauge, so naturally i was crapping my pants until i could pull over and pop the hood.

when i did though everything was fine, the coolant level in the tank was spot on, the top rad hose was really hot, other hoses were hot, i got my hand down onto the rad which was hot but the lower i went the cooler it got, so the bottom of the rad was quite cool ??

So whats going on here, its got a new water pump which i know is working fine as i checked it all when originally trying to figure out why it runs hot, but this is the first time the rad has been cool

Oh yeah, its a brand new rad too !

Scott

 

Heat rises, cold sinks-

 

So what temp are the fans coming on at, and what temperature thermostat .

I would take it to a shop and have them point a Infrared laser temp gun at the thermostat housing and compare that to the gage. Something does not sound right.

A typical coolant system.

 

Is your bottom hose collapsing?? Just a thought.

 

the hoses are all relatively new, i felt the bottom hose too and it was hot, but it wasnt nearly as hot as the top hose.

ive got a 180 stat in there, and my fans are on a switch, im very aware of the temperature gauge, which is an aftermarket digital one and very accurate. I turn the fans on when it gets to 200 degrees but yesterday it wasnt even cooling down according to the gauge.

Ive had the same setup from when i had the 5.0 engine in the car, and the old waterpump, old radiator etc and it stayed cool as anything, now everything is new it gets hotter !

Ive actually got one of those infared temp guns, i didnt check it yesterday as i was out in the car but last time i checked it everything seemed ok, the fans were holding the temp at 190 just running in the garage for a while

but yeah something wasnt right yesterday, especially for the time i had been driving the car and how hot the temp gauge said it was getting, the bottom of the radiator should of been hot, not cool to the touch

 

When my radiator did this, is was because I was dangerously low on coolant. You might want to do a full flush and clean, then burp the radiator well and see if that helps anything. That's the only thing I can think of because you have indicated everything else is "new"...not that something new can't fail, it's just unlikely.

 

Could do, its just annoying that everything is new and I got a much lower temp that hardly moved with my old engine and radiator etc, urgh

 

Sometimes air pockets can form in the heads where the sensor is placed. One way to purge the air is to jack the front of the car in the air and let the engine run to operating temp while topping off the coolant.

Barring any mechanical problems, you might want to try advancing the timing a few degrees to see if that helps. Retarded timing can cause lots of additional heat.

 

Its set at the stock 6* there's not many mods on the engine, Bosch 3 injectors, ecm has been reprogrammed by tuned performance, headers, exhaust, all emissions are gone