hey guys i have a 93 ford f150 5.0, i took off the stock fan, and put 2 12 electric fans, a few weeks ago my radiator blew so i changed it for a new one, and i noticed that it starts over heating on me, i also took off the thermostat and still my needle starts climbing, is there anything that i could do to fix that problem. when im on the freeway im ok but if im still for too long then thats when it starts climbing.

 

Suggestions, starting with the simpler stuff -
1) Validate the fans are turning the right way - pulling air towards the engine, and are engaging properly - at the right temperature.
2) Verify the water pump is moving coolant.
3) Verify airflow through the new radiator is not being restricted.
4) Verify the fans are not just recirculating air instead of pulling all air through the radiator - was there any shrouding included with the fans?

Wondering if the fans are big enough...?

 

yes the fans are pulling air towards the engine, and there was no shrouding included with the fans,. when im driving there is no problem, and when the truck is still it takes a while for the needle to climb, but when stuck in traffic it is an issue since traffic lasts sometimes over an hour stoping and going.

 

IMO, once a vehicle gets above 25-30 mph, the fans' effect is diminished due to the relative ram air flow.

Given that your problems seemed to have started with the electric fan installation - wondering how well the fans are working, as installed??

Without a shroud, the fans need to be pretty close to the radiator, otherwise they tend to follow the path of least resistance, which is to pull a higher proportion of air in from the sides of the gap between the blades and radiator, rather than pulling the bulk of the air through the resistance of the radiator.

A pic would be helpful, but offhand, suggest to look at ways to locate the fans closer to the radiator without interference (where the fan blades meet radiator).

 

Are your fans running all of the time? You should be running a fan switch that kicks in somewhere around 195 - 200*. My fans only come on after sitting at idle for at least 5 - 10 minutes. They kick in for about 30 seconds and cut off every few minutes until I get back up to speed. At highway speed, the fans do not operate at all. At highway speed, anywhere above 45mph, there shouldn't even be a need for a fan period if the cooling system is healthy. I run a 185 t-stat, factory radiator and the e-fans with the fan switch set to kick in at 195 and off at about 190.

Edit - here's some great reading if you do indeed have a fan issue. I run dual 12" chrysler fans and factory chrysler e-fan shroud. I tested using only a single 12" fan and with the exception of the fan running a little bit longer, it performed well with just one fan.

https://www.f150forum.com/f10/electric-fan-swap-152094/

 

Check for air in the coolant system. If there is a large air bubble it will thow off the temp sensor. Try running a scanner on it and see what coolant temp vrs what the dash is reading.

 

Couple questions. Where does the needle run at normally? Dual or single core radiator?

 

Both my 4.9 and 5.0 run right at the N. Both running 185 t-stats. the 4.9 runs lower than the 5.0. Just before the N. Every gauge is a little different. My 4.9 runs a single core rad and I think my 5.0 does too. Not sure though.

 

Put the mechanical fan back on and see how it does.

 

If it cools off on highway, the fans you put on arent moving enough air. When a vehicle overheats in town(stop and go) and cools off once rolling, its and airflow problem. And if it stays cool in town and heats up when rollign its waterflow problem.