Engine gets too hot when towing

[jodysutts]

Every now again I will hitch up the trailer to do various jobs and when im towing the temp gauge starts going into the red and I have to keep it cool as best I can.

This only happens when towing, the temp is perfect everyday and will remain perfect for months until I hook up the trailer.

Can anyone shed some light on why this is happening?

Cheers guys!

 

[zippy656]

Check water flow through rad

Thermostat could be stuck

 

[jodysutts]

I was thinking that it could be a stuck thermostat but would the engine overheat all the time then and not just when towing?

 

[AD Ent]

Its worth a try for what they cost

 

[solarman216]

viscous fan may have failed, unfortunately I do not know a way to test this, when you first start up and give it a little revs it should roar for a few minutes then go quiet, but all this proves is that it has not lost viscous fluid, it does no confirm that the valves inside work when it gets hot, the only other visual check you can make is the bi metal coil spring on the front is attached at both ends and that the centre spindle is free to turn, other than that I cannot come up with a method of heating this spring with the engine running short of removing the rad and holding a hot air blower directly at it to simulate how it would work in real time, trouble is piping the rad in remotely as would not run engine for long with no water, Rick

 

[macabethiel]

Heat

Extra power required when towing causes engine to run hotter due to load.

This then puts a higher demand on the cooling system to maintain the normal temperature.

If you are running hot then you have to consider the following.

1) Is the thermostat opening to allow full flow. (Cheap starting point to replace it)

2) Is the water pump working when as good as when new. Has impeller deteriorated.(Is it plastic or metal is the design prone to failure)

3) Is the radiator core capable of its original flow rate. (Modern coolants are pretty good at preventing them from blocking up but they do fur up with age ) Many aftermarket replacement radiators have fewer tubes per square inch than originals to keep costs down. Has it ever had any kind of stop leak added these products can block up or narrow the tubes,

4) Is the cooling fan working as it should. (Viscous fans are great but they do pack up)

I would try in order 1.4,3 & then 2.

I have simply put the heater on full with fan as a short term fix.
Don't like roasted feet though !

 

[firebobby]

Where does your temp gauge needle sit when at normal temp, on both my 3.0 and 2.7, it sits/sat just below halfway and stays there when normal driving or towing.