Lower than normal coolant temps

[Esilvester]

Hi.

When I first got my truck, I fitted a temp sensor in the top hose to keep an eye on coolant temps - as I was paranoid about the LN130's head.

(Fat load of good that did me, as when it went last year, it went with no warning)

I got used to the temps being 85-89 degrees both before and after the head repair.

A few weeks ago (and several thousand miles after I fitted a new head) I noticed that I have 67-71 degrees now - should I be worried? What does this mean?

Could this mean that the coolant pressure has increased for some reason and reduced the temperature? Heaters, MPG, performance, all unaffected.

Am I just paranoid?

[ezza24]

Sounds like your thermostat may be stuck open

[muddle]

Mabye viscous fan is coming on earlier or seized. Did you change rad with head repair and have you fitted a new possibly lower temp thermostat?

[bullet513]

due to outside temps being so low? my top hose guage runs colder the cooler it is out side, but engine temps remains normal

[Esilvester]

thanks for your replies.

I don't think the thermostat is stuck open - I can see the point it opens as the water gushes over the top hose and the temp shoots up.

The lower temperatures have not really affected it as I don't see much fluctuation over a few degrees between summer and winter.

Viscos fan - hmmm. That's worth checking out. I did replace that with the head (I broke the old one getting it off) so I'll check that out.

I guess I should also double check the calibration of this digital temp gauge with some boiling water, as it could be giving bad readings.

[Esilvester]

I have added some cheapo ebay self-adhesive heat-shield to the turbo.... I can't see that reducing the coolant temp by 15 degrees though....

Truck is running really well, maybe I should just relax....