[qcj]

Forest, coming home this week it was hot and the coolant temp. on my siverleaf would go up to 206 or 207 and them my fan would cut on and the temp. would go down to about 194 immediately. My fan does not cut on until about 205 or 206. Many times I can feel the fan turn on by a little jerk in the steering wheel, then I look over and down comes the coolant. Looking at the silverleaf it told me the max. temp. for that day was 208. My oil temp. runs about the same as coolant, just does not vary as much. Transmission temp stays at about 212. Most of my driving was small hills as in Ark. Mo. I'm pulling a 4200 pound jeep, driving 62 MPH.

[folivier]

Finally made it up I-70 to Heaton Bay campground. Ambient temp was about 85. Cindy drove the truck so I didn't have that 6500# anchor. I had to stop 4 times to let the engine cool down. Ended up keeping the boost pressure down to 10psi in order to keep it from overheating. The Davco fuel filter is full again so I need to change that before I leave here. And I have a fuel leak on one of the fittings on the bottom of the pro-check, so need to try and tighten that.
Hopefully once I change the filter the engine will run a bit cooler.
I did verify that the radiator fan is running on high when the temp gets over 205 or so.

[Fulltiming]

Sounds like you may have gotten some bad fuel for your Davco to keep filling up.

[qcj]

Yes, I was thinking the same thing. I have gone almost a year now and mine is only at one half. Of course I have only driven about 7 or 8,000 miles. I do use diesel Kleen and I don't know weather or not that would make any difference. I guess all of us have run into dirty fuel at one time or another. I did several years ago in my 07 and took three filter changes to correct to problem. Forest I wander if this could cause a heating problem?

[folivier]

Ok this is weird. After the engine cooled down the filter level came back down to about halfway. I tightened the fittings on the pro-check. I cranked the engine up and there is a leak on the pro-check but it appears to be from behind it. I saw Larry Weikart bypassed his a couple years ago after a talk with Newell. I'll call them tomorrow.
Anyway after a couple minutes of running the fuel filter level was to the top. What is causing that? Change it or maybe the pro-check is causing this? I wonder if the fuel leak could be causing air to get into the fuel line and the engine run lean, causing it to overheat?
Ok, y'all think about that a while. I'm going pressure wash the radiator. Carefully.

[Mxfarm]

Curious, running a diesel 'lean' - is that something Newell is saying or another source?

[folivier]

Just me trying to figure out why its running hot. I'll call Newell tomorrow and see what they say.

[Mxfarm]

Just throwing this out there -

But a diesel can't be ran lean. Reduce the fuel in the mixture you get less power - less power actually will give you lower temps. With diesels the it's overfueled or underfueled for the available air - overfueled = black smoke, underfueled = loss of/or less power. Let off the throttle and the injection pump reduces the fuel - air stays the same (turbos are a bit different). If you take a N/A diesel it's getting the same amount of air charge @ a idle as WOT. The only difference is the amount of fuel the injectors are spraying into the cylinder. Turbos change it a bit as the power goes up so does the amount of air being crammed into the cylinder. More air and you can inject more fuel w/o going into a overfuel state and only making black smoke. Black smoke isn't power it's only unburned fuel - but you know - probably - your not leaving any unused air in the cylinder. So your @ max power for the amount of available air.

Gas engine thinking doesn't apply to a diesel. So if your warmer than normal - I'd sure look on the coolant side first.

[HoosierDaddy]

I agree with Marc. Diesels operate under a stratified charge condition..Fuel is injected into the combustion chamber after it is fully filled with air. A/F ratios can reach 100/1 with no increase in combustion temps. More fuel means more heat on a diesel engine.
The lean mixture conditions a gasoline engine can experience happen under a homogenous charge where fuel and air are premixed before entering the combustion chamber. The A/F mixture must be kept closer to that 14/1 stoichiometric ratio to prevent high combustion temps.

[Richard]

Marc,

Excellent explanantion.

Forrest, you can remove the procheck without any causing any problems. However, its purpose is to self bleed any air in the fuel line. You would lose that function which is useful if you ever run the thing dry. The engine will eventually self prime and start. I learned this when I worked on the engine in 390.