Weird Overheating

[Lynden-Jeff]

Hey,

Just got back in from a 30 KM trip. I was going up a hill doing about 120 Km/h and at the top I noticed the check guage light was on and my engine temp was on red. I immediatly pulled over and within 10 seconds of stopping the heat needle had dropped to half way between good and red. I sat for another 5 minutes and then preceded to go and all seemed fine, I hope I caught it in time. What would do this? I had my snowplow on but have never had heating issues with it on before even at these speeds. Coolant level was fine. Any suggestions? Any possibly I did damage by overheating? One thing I noticed was a weird air Whooshing sound like you would hear on a big rig.

Thanks
Jeff

p.s ANOTHER thing I just noticed is the trucks been off for 20 minutes and I opened the coolant overflow bottole lid and there is no pressure left over. Why would this be?

 

[grandma99]

I run a plow on mine too, the engine temp will spike a little at times, but I've never had mine redline. The weird air whoosing sound you heard was the thermal fan clutch kicking in, it locks the fan to the fan pulley, so your fan is turning full speed instead of slipping. That is also why your engine temp went back down. If it's been a while since you've run higher speeds with your plow on, it's likely your fan clutch was sticking, and didn't kick on when the engine started to get hot. I bet you'll still hear the fan from time to time, but shouldn't have that high of a temp reading again. Keep an I on your temp guage, and run with your plow as low as you can without it hitting the ground.

 

[melmount]

any way to not have a fan clutch? is it electric of some sort?
can you use a fan spacer and no clutch? have full fan all the time? like older hot rods? not sure if it works this way. never looked at my fan.

 

[RoyBoy]

I cannot imagine that a plow could cause enough loss of airflow to cause overheating, especially this time of year. I have the front of my truck totally covered with a winter front and gross 16,000 lbs, never get the water temp over 180*F. The ambient air is just too cold. I would first suspect a bad temp reading, or perhaps a stuck thermostat... this is one reason why i have a real temp gauge in the cab, I don't trust the factory gauge. The reason your fan kicked in was because the temp probe was telling the PCM that the engine was hot... although I doubt it really was. I'd check the fluids and keep an eye on it... also consider getting a set of gauges, they are very valuable for diagnosis and protection of your truck.

 

[RoyBoy]

any way to not have a fan clutch? is it electric of some sort?
can you use a fan spacer and no clutch? have full fan all the time? like older hot rods? not sure if it works this way. never looked at my fan.

Running with a solid fan would be a huge power draw on these engines because the cooling system is actually well oversized for the application. That's why the fan is electronically variable speed.

 

[Lynden-Jeff]

I cannot imagine that a plow could cause enough loss of airflow to cause overheating, especially this time of year. I have the front of my truck totally covered with a winter front and gross 16,000 lbs, never get the water temp over 180*F. The ambient air is just too cold. I would first suspect a bad temp reading, or perhaps a stuck thermostat... this is one reason why i have a real temp gauge in the cab, I don't trust the factory gauge. The reason your fan kicked in was because the temp probe was telling the PCM that the engine was hot... although I doubt it really was. I'd check the fluids and keep an eye on it... also consider getting a set of gauges, they are very valuable for diagnosis and protection of your truck.

Hey,

Im getting a bullydog PMT on monday, mostly for the gauges and some fuel economy. I thought that other then pyro it uses the stock computer for monitoring values, will this suffice?

Cheers
Jeff

 

[DaveBen]

I would NOT trust any Ford Gauges or sending units. Get something you KNOW is good.

Dave

 

[RoyBoy]

Hey,

Im getting a bullydog PMT on monday, mostly for the gauges and some fuel economy. I thought that other then pyro it uses the stock computer for monitoring values, will this suffice?

I don't know for sure but I assume that it gets the coolant temp signal from the OE probe. That will be better than the dash gauge which is basically a 3 position idiot light. I still prefer a separate probe, but I do get on the extreme end of heavy towing, so you might be fine.

 

[grandma99]

I checked into this further, because mine does some of the same stuff, and Ford actually has a bulletin on it. If your truck does not have the plow prep package, running at highway speeds can cause the truck to run hot due to disruption of air flow, it can even cause the fan to spin backwards. Ford offers a different fan clutch for trucks with the plow prep package, and recommends the purchase of this different fan clutch.