engine running hot what should I check first

[mm73]

I drove my deuce down the road the other day and realized the temp gauge was slowly climbing and eventually pegged out. It took it about 10 miles to do so. I stopped and checked and nothing was leaking and the coolant was full and clean not all nasty looking. I was just wondering where to start checking first? should I just go ahead and change out the thermostat or the gauge or both or the water pump? Or is there something else I should be doing? Help point me in the right direction, Thanks.

 

[Keith_J]

Was it boiling over? Did you have coolant flow?

I would start with the sending unit and gauge. Then thermostat and finally, the water pump.

 

[mm73]

That sounds like a good Idea. It was not boiling over or steaming or anything like that. I will check the sending unit and the gauge 1st and just see. And then work my way to more expensive parts.

 

[scrapman]

Loose belts? The fan puts enough of a drag on the pump that at speed loose belts will slip & the pump does'nt move water. Use a meat thermometer to check the coolant temp in the radiator. Should be close to what your gauge is reading. Remove the cap before bringing the motor up to temp to avoid having hot pressurized water spraying on you.

 

[bryan70546]

I drove my deuce down the road the other day and realized the temp gauge was slowly climbing and eventually pegged out. It took it about 10 miles to do so. I stopped and checked and nothing was leaking and the coolant was full and clean not all nasty looking. I was just wondering where to start checking first? should I just go ahead and change out the thermostat or the gauge or both or the water pump? Or is there something else I should be doing? Help point me in the right direction, Thanks.

You would not happen to be the same guy with the nice Black dodge duelly .
With a Brother named David

 

[Jake0147]

An infared temperature gun is a quick way to find stuff like this. If the radiator is cold, suspect a thermostat. If the radaitor is hot on top and dropping too much temperature, suspect crud in the lower hose or other flow issues. If the engine's temp does not corrspont (somewhat) with the gauge reading suspect gauge issues.

Typically a gauge doesn't "slowly rise" when it fails. It might work intermittantly, it might fail high or low, it might bias high or low, but I'd start with verifying some temperatures...

 

[6x6guy]

Check the radiator on the outside from the bottom to the top for heat displacement, the heat should be consistent for both top and bottom if not you have a blocked radiator and will over heat with in a short time- 40+ years of rust and gunk in engine coolant system the can really take a toll on the system, with a blocked or plugged system- not enough cooling of the fluid through the fins will not properly dissipate the heat.

 

[mm73]

Hey thanks so much for all of the input. this site is a god send. Im going to start checking this stuff out today. Oh and bryan 70546, Yes that is me with the black megacab and a brother named david. I actually just called you to ask you a question but got your voicemail so I figured you are working offshore. If you get a chance check your vmail and call me back if you can.

 

[cranetruck]

Use your DVM and check the sending unit for approx temps. It can be hooked up while driving, get readings and compare to the table below.

 

[LanceRobson]

I may be confused but, if you checked the coolant while it was overheated, you'd have had a geyser of steam and coolant. When did you check it?

If you checked it when the temp showed hot and you didn't get a geyser, the thermostat may be stuck closed or close to closed.

Were the belts tight?

If checking the sending unit doesn't help, loosen the belt and turn the pump by hand. It should turn freely with no binding or noise.

Good luck.

Lance

 

[frodobaggins]

Use your DVM and check the sending unit for approx temps. It can be hooked up while driving, get readings and compare to the table below.

Thanks, been looking for something like that.

 

[mm73]

Well the good news is that I finally got the batt charged up to par and when I began to drive it to get it to heat up again I drove it faster than the last time. About 45 to 50 mph for about 10-12 miles. When I got to my house I parked it and it never got over 180-190 on the temp so Im thinking it might have been a stuck t-stat. But the bad news is when I went to look under the hood to check things out I noticed that I had oil all over the bottom of the engine and on top of the front axle. I got my brother to look at it with me and it looks like its all coming from behind the harmonic balancer so I then started it up and set it at 2000rpms and sure enough you can see it start dripping from behing the harmonic balancer. does anyone know if you can just remove the radiator and then get to it to change the seal out or do you have to pull the whole engine? Any help is greatly appreciated.

 

[bryan70546]

Sorry to hear about this , look like we have some work to do.
Bryan

 

[OKCMoparGuy]

I'm not a multifuel expert, but on most engines when the front main fails you have to drop the oil pan to pull the front timing cover which houses the seal. Some of the other guys can confirm this.