2003 cummins Air clutch cooling fan

[crane operator]

2003 cummins ISL 330 (basically a cranked up 8.3)

Has a air fan clutch, the fan kicks on by temp/ECM, and the clutch engages, but it just seems like it isn't moving the air it should.

We have two cranes like this, and the other one sounds like a helicopter taking off when the fan kicks in, but this one, I just barely hear it kick in, and it isn't doing a good job cooling. I've got to be real careful with the throttle or I'm overheating.

Can the clutch slip and not go to full speed? Low air from the solenoid? or bad solenoid? It kicks on and off so I think the solenoid is working correctly, but I can't be sure its putting all the air it needs to the clutch, I guess the clutch could be leaking air also- I've had that before.

Any help appreciated.

 

[ahart]

On my 8.3 ISC, it takes air to disengage the fan clutch. If my air is low when I first start the truck, the fan is turning wide open then after the air builds, it disengages. I think it’s definitely possible that the clutch is slipping, I replaced my fan drive last year due to an air leak. If yours uses air to disengage like mine, you should be able to drain the air tanks and see if you can move the fan blade. The belt should hold the drive pretty tight if the clutch is good. I’m no fan drive air clutch expert but that’s what I’ve seen with mine.

 

[funwithfuel]

Both kysor and horton have provisions for lock screws. Basically holes to threaded holes to lock the fan to the driven hub. If it's air, it should be full lock up, no slippage. If you can take a pic of the part tag, you should be able to Google the procedure for screwing it together.

 

[funwithfuel]

Maybe take a peek at this.https://www.roadtrains.com.au/tech-tips/how-a-horton-fan-clutch-works/

 

[Birken Vogt]

Around that era different fans on different trucks had different pulley diameters for different fan RPM. Just whatever they decided they needed. I would compare the crank and fan drive diameters on the trucks you are comparing, first, as well as the size and number of blades on the fan, in case there is nothing wrong and it just works the way it is supposed to.

You may also be able to select a smaller fan pulley for the troublesome one to get more RPM if you decide that everything else is already good.

 

[crane operator]

I think I'm going to lock the fan fully up with the two bolts, then see if that gives us what I think should be full speed. If that does, then I'll look for why it won't go full speed.

 

[funwithfuel]

If it's slipping, probably a worn clutch facing. If it was leaking air, I would think you'd hear it.

 

[crane operator]

Air solenoid is working correctly. Fan hub is not leaking air when engaged. We plumbed straight shop air to it with the engine off and it holds. I think the friction disk is slipping. We can't get it bolted up, so are removing fan covers and blade to get it bolted up and then give it a test run to see if that improves air flow.

So I had the IR temp gun out when I was diagnosing today. The engine has one coolant line (2 1/2" or so) going to the radiator, after the thermostat- it enters the radiator 1/2 way up the drivers side. Passenger side has a same size line, coming out 1/2 way up the radiator, for the cool water running to the engine.

Temperature differential from one side of the radiator to the other started out 40 degrees difference, and stayed that way all the way to full operating temp. I was seeing about 180 coming out of the engine, and 140 at return to engine. So a pretty regular 40 degree differential hot side to cold side of the radiator.

The other engine I have that's just like this one, the differential was similar as it was warming up, until the thermostat opened up, and then I was only seeing a 10- 15 degree differential from hot side to cool side of radiator. This engine does not have cooling issues like the other one.

So in addition to my fan issues, I'm wondering if I could have thermostat/ water pump/ radiator flow issues. There's no cap on the top of the radiator, so I can't really see if I have good flow. I could have a thermostat that's stuck just a little way open, restricting the flow from the water pump, or a bad water pump impeller, or simply a clogged radiator with poor flow.

The engine with good fan and flow, the fan will come on for around a minute or so and cool from 200 down to 180 on the gauge. The engine with slow fan the engine fan will come on and have to run for around 3-4 minutes to get a similar cooling drop. This was tested with both engines turning 1500rpm or so, with hydraulic pumps engaged to generate heat while sitting at the shop yard.

So am I right in thinking I have too much differential from hot side to cool side of the radiator, and have a problem other than just my cooling fan?

 

[funwithfuel]

It sounds like you definitely have a flow concern. The quick, cheap and easy thing is to pull the T-stat. Suspend it in a can of water. Slowly raise the temperature of the water to see when she cracks open and at what temp she's fully open.
There's no extra coolers in the return side, correct? No plate cooler for the trans or hydraulics , fuel or engine oil which may or may not be on both machines.
I just re-read the last comment. Let's see how it behaves with the fan "locked in"

 

[crane operator]

Trans and hydraulic have their own separate coolers and fans. I think the engines and cooling systems are identical.

The only other difference I haven't mentioned, is the one that overheats has green antifreeze, and the one that cools correctly is running the red coolant. I think I should also check the green coolant and see what its at for a mixture. The one that gets warm is a "new to us" crane that I have no history on.


When driving down the road, the crane with good engine fan cooling- that fan will run maybe 10-20% of the time. The engine with poor fan flow- the fan stays on probably 95% of the time. It rarely kicks off.

 

[cfherrman]

Take a shirt and try to hang it outside the radiator, it should stay up by itself.

 

[Truck Shop]

If the hub was slipping you would hear it plus the facing material will be raised at edge.
Are the actual fans identical? Green freeze-silicates some how I think that rad is lost 20%
of it's cooling ability.

 

[crane operator]

Take a shirt and try to hang it outside the radiator, it should stay up by itself.

Would if I didn't have a outrigger and secondary screen in front of it. May be able to squeeze one in from the bottom, but I'm not sure.

If the hub was slipping you would hear it plus the facing material will be raised at edge.
Are the actual fans identical? Green freeze-silicates some how I think that rad is lost 20%
of it's cooling ability.

Need to count blades and measure pulley to see if fans/ speed are the same. Can't hear the friction disk slipping, but it doesn't sound the same when it kicks on, and doesn't seem to move the same amount of air.

You may be entirely right on the radiator being plugged. I think we'll check coolant mixture and thermostat first, I'm not sure how bad a water pump is to look at on this ISL. Pulling radiator is going to be last on the list, it will be a job to get it out.

One of my guys got the screen out and has started pulling fan, once we get blade off, we can lock up the hub (one of the bolt holes is not wanting to start- so thread cleaning means blade off).

 

[Truck Shop]

If the core is partially plugged externally it won't pull as much air plus sound different.
On grain trucks hauling from field, especially harvesting peas the leaves will plug a rad
and cut air flow so much you can't hear much action from fan.

 

[crane operator]

This thing came from a dusty environment, so a good radiator cleaning is going to be in order also. I think with the fan blade out we will have a lot better access to the inside of the radiator and can try to blow/ wash it out.

 

[funwithfuel]

I was thinking last night, you should have a vent hose from the surge tank to the thermostat housing. If any trash get in that ⅜ hose and plugs it, you wind up with aeration issues sometimes. I would think once you get your airflow squared away, you'll be in a better position to troubleshoot.

 

[crane operator]

Cleaned the radiator. Locked up fan. no real temp change, still was running too warm.

Checked and replaced thermostat today, it was stuck.

The big temp differential from side to side went away, and couldn't get it above 170 or so on the gauge, with pumps in at 1500 with locked up fan. Before thermostat change, we could easily get it to 200 on the gauge with the pumps in.

Got the opportunity to replace some pretty stiff radiator hoses too, they needed changed and with it drained to do thermostat was a great time to do it. We did flush it all, and went back with red coolant.

Thanks guys.

 

[cfherrman]

I'll try to get closer pics on Monday, he built a rat rod two stroke and I think the booms are on it