05 F550 overheating

[Mike Jeanotte]

Truck came in during colder temps around 30 deg with fan running often. Monitor ect and eot were around 205-210 replace t-stat cust needed truck asked to see if it made any differenct came back about 2 weeks later said fan still runs often. temp same I remove the tin grill inserts cust had road test temp around 200 deg and fan didnt run any more. cust took truck. About a month later cust stated it over heated. He was uanble to bring in right away but is was very random temp on gauge peged 3 time in 4 days. He stated temp on t-stat housing was 300-350 the various time he checked it. but was not pushing any coolant out and fan was running. I remove water pump didnt find any problems. Service manager and I decieded to replace water pump and replace t-stat again, Truck made it about 1 week and gauge peged again, this time cust said it did push out some coolant. I replace fan clutch we drove little over 100 miles with no problems. Cust is not convinced we fixed it. and we may not have. Any Ideas Hotline said if coolant temp was 350 deg stand pipe should be melted and engine should be damaged. Coolant and oil do not smell burnt. No damage to stand pipe Tried wiggle wiring to sending unit no problems found. Cust needs truck due to their busy season. and is unable to leave with us for very long. Have prefomred flow tests that I know of and everything seems ok. I would think if it was low or excessive flow It would act up more often than every 400 miles. This engine is a reman that was installed about 70,000 miles ago. Any Ideas.

[Brad Clayton]

Quote:

I replace fan clutch we drove little over 100 miles with no problems. Cust is not convinced we fixed it.

How far does the customer think this thing needs to be road tested to verify a repair? Most trucks get driven 5 miles if that.

and we may not have. Any Ideas Hotline said if coolant temp was 350 deg stand pipe should be melted and engine should be damaged.

The hotline is a bunch of guys reading a computer screen for the most part. You have to look long and hard in the bunch they have up there to find an actual person that can help out with genuine know-how.

We had a truck that was dealer swapped once. An old timer used car jockey went and got if from who knows where. Sometime during the trip the bottom hose clamp broke and all the coolant departed the motor. The guy being a total fucking retard decided it would be in his best interest to keep on truckin and hope he made it back to our dealer.

Well when he arrived the thing smelled to high heaven and the block was glowing red, the BLOCK, as in ENGINE BLOCK. Guess what, the truck got an oil change, a clamp and some good ol gold antifreeze and is still in the hands of the poor ol unsespecting customer who bought it 7 years ago.

So should the standpipe have melted on the unit in the story above? Hell yeah. Did it? No it didn't. Sometimes things are on a case by case basis. After a 100 mile road test and no problems noted, should there be any further investigation into the vehicle you are working on? I would think not, especially if you are driving it the way the customer is.

[Aaron]

I had one that had an oil temp out of range code at 255 deg, melted standpipe.

 

Customer unplugged the fan and ran it at 30% TP for 31 minutes till it set that code and shit started going wrong.

[Jim Warman]

Looking at this a with a bit of logic (and some skepticism).... customer states that the thermostat housing is at 350 degrees F and the coolant isn't percolating in the system? The rad cap isn't whistling dixie? I'd be asking the customer how he's coming up with 350 degrees.

 

Does the customer state that the fan is running often? From my experience, you can really tell when one of these visctronic fans kicks in - many customers hearing it for the first time share the "holy mother of God, what is that?" train of thought. FWIW, if the fan is running when the overheat is happening, chances are it isn't the fan that is the problem.

 

Some things to consider... Is the truck overheating (blowing coolant out of the degas bottle, giving the "thump - thump - thump" sound of coolant percolating in the cylinder heads) or is it running "warm".. Going out on my favourite shakey limb.... I'm assuming "running warm" (especially if coolant loss isn't a concern).

 

If this truck is being operated in "light" conditions (lightly loaded, mid to low speeds, that sort of thing), it is entirely possible that there is enough cool air passing through the cylinders to moderate engine temps.... Load the sucker up once in a while and things might get interesting.

 

The cooling stack... in my humble experience, the cooling stack is the most overlooked cause. The usual problem is that the front face of the radiator collects a fine fur coat - to the point that airflow across the coolaing stack is nil. Every layer of the cooling stack deserves to be inspected.... but the radiator... if nothing else - check the radiator.

 

A more remote possibility is coolant strength. When we consider the automotive cooling system, we need to consider the thermal efficiency of the fluid... Straight water (one would need to consider corrosion inhibitors, pH and nitrite levels and, of course, water pump lubrication) absorbs the hea from a cylinder head or engine block "quickly".... it's problem (other than the considerations I mentioned) is that it has a comparitively low boiling point (freeze point is a consideration that isn't pertinent in this case) - even with cooling system pressurization.

 

If we add a glycol based antifreeze, we are given a freebie.... boiling point of the coolant is raised - even without pressuring the cooling system. But there is a trade off. Glycol absorbs heat more slowly than straight water. If our glycol content in the coolant get's too high, I can't see if <causing> the concern.... but I can certainly see it exacerbating the concern.

 

Good luck with your patient.

[dieseldoc]

Hi mike I know you and I kind of got off on the wrong foot the first time around and that was my fault. I apolagize again However I have talked to the operator of the 550 in question and since you guys put the radiator in it he said it has been working well so far. He hardly hears the fan run anymore. The temp drop on the new rad is much better as well. Since it is intermittent only time will tell, but it is looking good so far. It was definitely a tough one to figure out I am sure. If the radiator was the casue you think it would have been a consistent problem, sort of defies logic. I know it is tough to troubleshoot when the customer keeps taking the truck away before you are comfortable you got it fixed or finish your testing. Thanks for the patience with us, This spring has been crazy busy.

[Aaron]

He probably just turned the radio up

 

[Mike Jeanotte]

Hey Robert I took the tanks off that radiator didnt see much a little casting sand probablly from when the truck was new. But it looked pretty good I know I cleaned the outside of the cooling stack and I think you guys did also. Dosent make a lot of sense but hopefully its taken care of.

 

With this rain coming through Im pretty sure there will be at least a Grand Forks truck coming down with a lack of power. You know how this business goes we complain when were busy and complain when were slow.

[dieseldoc]

I hear ya about the busy. When I punched out for day 14 in a row today I was at 75 hours this week, and I get to start a new week tomorrow. That is wierd I figured for sure the inside of the radiator would have been restricted at least a little to cause the issue it was having. Sometimes things make no sense. But hey if it fixed it that is all that matters. I was talking to one of our customers yesterday and he said they are about half done with spring work. YAY!!!! maybe a light at the end of the tunnel. I would rather have a few 100 hour weeks than 2 months of 65 hour ones.