My engine temps have been higher than I'd like to see lately. 208 unloaded, A/C on, pulling a mild grade at 60-70 mph. 234 pulling 10-12k, no A/C same grade at 50-55 mph. I pulled the cat and put in a flow-through muffler hoping it would help, but it really didn't. '04.5 HO w/ auto. Are these normal temps? The numbers are from my attitude display, not guesses. Can I lockup the fan clutch? What aftermarket options are there?

Start with a good cleaning (pressure washer) of the a/c condensor, intercooler, and radiator.

Those clutch fans aren't the greatest. If you replace it, make sure you break it in properly.

The radiator would be my last guess.

Those temps don't seem too bad, but I don't remember exactly what mine used to run. The guage did move around quite a bit.

Ummmm. 234 sound really high to me! What is your EGT running?

Is your fan clutch kicking in at all? If you do replace make sure to go oem. I used a napa one and it didn't work very well. Put OEM in and it was fine.

If your EGT's are at a safe level it should cool it fine. The only time mine gets hot is when I'm pushing the EGT's going up a long grade. I would agree with cleaning the radiator, that crank case vent tends to gum up the radiator.

Those clutch fans aren't the greatest. If you replace it, make sure you break it in properly.


Not to hijack, but I've never heard of breaking in a fan clutch. How do you properly break one in?



Rob

I had this problem. I pressure washed it and all but it still was hot. You need to pull the radiator. I pulled the radiator and was amazed on how much dirt was packed in there after I had just pressure washed it a week earlier. I washed it out and havent had an issue since.

Mike

Not to hijack, but I've never heard of breaking in a fan clutch. How do you properly break one in?



Rob

You rev the engine at 2000 RPM (right away) for a few minutes. You will hear that the fan clutch is engaged from the start, then it will go off after a couple of minutes. I don't remember if you are supposed to repeat the process 1 more time or not, but that's the break in process.

Any excessive slipping of the torque converter? (On my gasser when the t/c was slipping the engine temp would climb from the extra heat being added to the rad).

234 isn't horrible, but its on the high side.

Ummmm. 234 sound really high to me! What is your EGT running?

EGT's are under 1100, under load, around 850 on the highway and cools to 350 within a minute or so at idle. I've never sounded my EGT alarm, set at 1250

Is your fan clutch kicking in at all? If you do replace make sure to go oem. I used a napa one and it didn't work very well. Put OEM in and it was fine.

I can't tell. On my Dmax, I could hear the fan kick in, are the fans on the dodge's as audible? My truck idles up when it's over 200, but no excessive fan, or other noises

Any excessive slipping of the torque converter? (On my gasser when the t/c was slipping the engine temp would climb from the extra heat being added to the rad).

234 isn't horrible, but its on the high side.

The edge recorded a 10% slip, which it's done since I put it in. I am waiting on a price for a new billet convertor though, considering the weight of my tractor/trailer and living in the hills

Pyro. probe on the outlet or inlet of the tubine housing? If you are on the outlet then 1100 constant is really pulling hard and I'm sure you have upped your fuel a bunch. What is the boost pressure at 1100 deg and what RPM? How heavy are you pulling and what grades?

Pyro is in the center of the manifold, pre-turbo. Fuel is bumped, boost probably high 20's, rpm, not sure 2300? Tractor and trailer weigh in about 12k, I don't know the grade %

That EGT doesn't sound so high then. It is at least 200 to 300 deg cooler at the turbo outlet depending on the boost level.

SHould I be able to hear theh fan when it's locked up?

I can't tell. On my Dmax, I could hear the fan kick in, are the fans on the dodge's as audible? My truck idles up when it's over 200, but no excessive fan, or other noises
Heck, yes, the fan on my 99 24v Dodge CTD 2500 is audible. The first time the clutch locked up, I was towing 9,000 lbs. up I-70 westbound out of Denver. Makes one heckuva roar.

I'm going to look into a new clutch then

I doubt a clutch fan is the problem at freeway speeds. At 70mph it should be ramming plenty of air through the radiator. If it was after you slowwed down from freeway speeds then I would think fan clutch. I really think the radiator isnt getting enough air flow.

Mike

Low airflow can also cause the fan to not kick on. Wash your radiator from the engine side out. Best way is to remove it like was already suggested. I bet you get a bunch of crap out of it.
Travis..

235 is too hot for a diesel. On medium duty and heavy duty diesels, typical fan on temp is 210f. On the dyno with a full load, they normally will spike up to ~ 212f before cooling off.

When the cooling problem is at highway speed, IT IS NOT A CLUTCH FAN PROBLEM!!!

At highway speed, you have enough ram air flow to cool the engine. I would pull the radiator out and blow it out with compressed air, not steam clean it. Also take a peak inside and see how much scale build up is in the radiator.

I remember one of my radiators looking extremely clean looking in from the cap housing, but in the exact area where the fan sucks air, it was all jacked up. This was on the inside of the radiator and found only after it was disassembled.

I agree with waht the others are saying about the radiator being the problem.

ok, how much coolant does that bad boy hold, so I can have it on hand to re-fill after puling it? I've got a 13 hp 4000 psi pressure washer, I should probably dial the reg out some?

The truck only has 50 k on it, should I take the rad somewhere to be cleaned inside? Or just start with trying to clean the fins out?

Just start with cleaning the fins. If you take it to a rad shop, chances are good you will come home with a new radiator. Save yourself some money and clean it externally first.

First of all, make sure you get the correct coolant, and most people at the local parts stores will not know the difference. I always bite the bullet and get it straight from the dealer and keep the receipt. It's a long story, but basically I was denied a Ford V10 motor because they said I was using the wrong coolant. :mad:

You can pressure wash it yourself and just keep an eye out as too how much dirt comes out. Don't forget to make sure you clean the A/C condensor as well (but don't remove it!) If you don't see quite a bit of dirt getting rinsed out, I would take it to a professional and be prepared to buy a new one...or put some money into your old one.

Will do, seems amazing that enough dirt gets past the condensor, tranny cooler, and intercooler to clog the rad. That's quite the stack in there. I'll try to hit it in the truck before I head down the hill and pickup the parts to do a thorough job this weekend. I do need to pull my cat up the hill tomorrow, I'll just try to do it before it breaks 100

Sounds like you already know but.... One wrong swipe with that powerfull pressure washer migh just fold over half the fins on whatever cooler it hits...

Pure water is the best remover of heat... Antifreze raises the boil and lowers the feeze temp but does not transfer heat nearly as well as pure water... Is there any chance you are too high on the antifeze and that you need more pure water in your mix? Also bottom radiator hoses can flatten out under a vaccuum. That is why some of them have wound springs in them - maybe worth a check?

There has been more than once on various vehicles that I have turned the heater to full blast on a hot day climbing a grade to keep the engine temps down.... Sucks, but better than the engine overheating....

Sounds like you already know but.... One wrong swipe with that powerfull pressure washer migh just fold over half the fins on whatever cooler it hits...

Pure water is the best remover of heat... Antifreze raises the boil and lowers the feeze temp but does not transfer heat nearly as well as pure water... Is there any chance you are too high on the antifeze and that you need more pure water in your mix? Also bottom radiator hoses can flatten out under a vaccuum. That is why some of them have wound springs in them - maybe worth a check?

There has been more than once on various vehicles that I have turned the heater to full blast on a hot day climbing a grade to keep the engine temps down.... Sucks, but better than the engine overheating....


I've got one hose before the regulator on my house with about 150-175 psi. I'll use that for my pre-rinse this morning. I can dial the pressure washer down to 0 and will dial it down before using it for sure. I bought the truck with 20k on it last year and haven't done jack to the coolant. Should be factory. I did toss in a bottle of diesel-wetter a couple weeks ago and didn't notice any difference. I think there is definitely an air flow problem. The fan not kicking on at all concerns me too. It gets warm coming up the hill at 50-55 mph, but once I hit that first light in town and continue uphill is when it usually gets its hottest. Heater deosn't seem to do much, I've tried that. I'll check the lower hose.

On the '05 PSD the other day pulling about 15k at 55 mph it climbed to 238 deg F. Fan clutch was not working. (Couldn't hear the fan come on) Dealership replaced the water pump and fan clutch and it worked great.

Thats not that old of a truck to be the packed off of a radiator but depending on the conditions you live/drive in, I suppsos it could get bad.

I'm a contractor, but for the most part don't drive in dusty conditions. I'll get a price on the fan clutch replacement, looks to be a PITA

If cleaning the radiator doesn't help, I'd also pull the water pump to see if the impeller is still in good shape and not half corroded away.

Another thought, on the Ford there was a TSB and a flash as apparently the ECM was not engaging the fan correctly in some models. In our case itdidn't help, but certainly a cheap/easy fix.

You should be able to use shop air with a rubber tip blow gun to blow through the radiator from the engine side out. The clutch fan will come on at freeway speeds with the temps the way they are (HOT!) if the engine requires it and you will be able to hear it. I have'nt seen any mention of thermostat so far but they are cheap so if your still having problems I'd change it before pulling the waterpump.

Called a cummins shop and he gave me a quick test for the fan: "Drive it around until it gets above normal, turn the truck off, get out and try to turn the fan by hand. It should be pretty much locked up."

I could spin it by hand a get a couple blades worth of "spin" out of it. On flat ground at spedd, it's just above what I would call normal, but as soon as I hit the grades and slow a bit, it starts to climb and once in town, it gets worse. Today I towed up a shorter, slighly steeper grade and hit 241, with the heater cranked at about 30-35 mph. The fan is not kicking on. The truck shop said it's pretty common. With 52k on it, the dealer didn't suspect internal clogging ro corrossion since I have the long-life coolant from the factory.

Does the fan hub look to be leaking oil from the backside of it? That is an indication of viscious fluid loss which is whats inside a thermostatic style fan hub.

Can't remember, but there does seem to be some oily dust on the intake tube, which suprised me, could be from the clutch?

uhhhh...the tstats on these things ain't exactly cheap........like 40 bucks or so

Low airflow can also cause the fan to not kick on. Wash your radiator from the engine side out. Best way is to remove it like was already suggested. I bet you get a bunch of crap out of it.
Travis..

Wilson, save your money and try this
remove the radiator and clean fucker out...

uhhhh...the tstats on these things ain't exactly cheap........like 40 bucks or so

I'd rather spend $40.00 for a T-stat than 3K-4K on an engine.

Can't remember, but there does seem to be some oily dust on the intake tube, which surprised me, could be from the clutch?

The fan clutch oil is very thick and usually does'nt fly around.

If it is getting hot around town that is a sure sign of the fan clutch not working. Diesels run cool around town unlike a gasser.

Get it fixed soon! 241 deg!!!:eek::mad3: Thats too hot! Your going to blow a head gasket or something...

If it is getting hot around town that is a sure sign of the fan clutch not working. Diesels run cool around town unlike a gasser.

Get it fixed soon! 241 deg!!!:eek::mad3: Thats too hot! Your going to blow a head gasket or something...



The cummins shop said it was definitely hot, but around 260 is when they would start recommend changing out tstats and gaskets from overheating them.

i would change the thermostat for sure its easy and could solve your problems ,just make sure you get one from a cummins dealer some have been know to go bad within a few months but its a dollar saver if you think you have to flush a radiator or a intercooler
p.s if you are running a air operated cooling system (air operated clutch)then its proberly your actuator (only in heavy duty trucks not rams)

Maybe my reasoning is wrong on this but here it goes:

-When driving downhill (unloaded) or on flat ground at highway speed temps are around 190-192 degrees. Slighlty warmer than the 187 degrees that I remember seeing as average temps. If I accelerate hard (onramp), the temp climbs to about 205, but fairly quickly cools back to 190-192. No sound of a fan or nothing.

-Driving uphill (unloaded) temps are around 200. As soon as I hit town and slow down, temps climb to 205-208 and don't go down.

-Driving uphill with my trailer empty (4k) temps pretty similar to above, may hit 212 in town.

-Driving uphill with trailer and skid steer (12k) temps in the 220 range. I hit 241 on a steep, windy stretch of road at about 30 mph. Coming up the normal route I hit around 230 jsut before town adn continues to maintian taht heat in town (all uphill no faster than 35 mph).

-Seems to me the tstat is working in that the engine stays coolish going downhill and cools down after hard acceleration. I suspect the fan because things really heat up when I slow down, or under heavy load. The radiator could still be clogged, which I'm understanding some of you say will keep the fan from engaging? Now does the rad. have to be pulled to change the fan clutch? If so, I'd just as well take it to teh cummins shop and ask them to thoroughly rinse out the radiator when they pull it, or the fan. I really just don't have the time to pull the radiator, rinse it and put it back in to find that it wasn't the cause of my problem.

If you end up dumping the coolant for any reason, like cleaning the rad fins, replace the thermostat while you're there. You asked how the rad can get plugged, and not all of the other shit up there? The rad has more fins per inch than the others, so it collects more shit. Wash your radiator and replace the stat and you will most likely be good. If it ends up being the fan, you can change that without dumping the coolant or pulling the rad.
Travis..

If you end up dumping the coolant for any reason, like cleaning the rad fins, replace the thermostat while you're there. You asked how the rad can get plugged, and not all of the other shit up there? The rad has more fins per inch than the others, so it collects more shit. Wash your radiator and replace the stat and you will most likely be good. If it ends up being the fan, you can change that without dumping the coolant or pulling the rad.
Travis..

Is it easier to pull the fan and wash out the rad with it in the truck, or just pull the radiator? I'll grab a tstat and coolant when I'm in town

I did the radiator recently on my 99 Dodge 24v. Takes a pair of hose clamp pliers and a 10mm socket. Don't even need to loosen the belt, or touch the fan.

I'd rather spend $40.00 for a T-stat than 3K-4K on an engine.

me too, I was trying to get at the fact that it won't cost 40 bucks or more to clean the rad/condensor/intercooler unless he uses a pressure washer and damages one of them.

Got coolant, and a tstat will pull everything out after I go get some pliers.

Completely pressurewashing my rad inside and out, very carefully then takin a rad comb to straighten out the fins is part of my yearly maintainence on the DD. Learned to do this as a young punk who liked to run mudholes. Just doing it in the truck does nothing but ram the mud and crap from AC to the rad.

Pulled the intercooler, loosened other coolers, shrouding, and radiator only to find.... a blown fan clutch. The front of the fan has a clear oil bath and accumulated dirt on it. Yeah there's a little bit of stuff in the radiator, but not enough to keep the motor from cooling, as I suspected. This puts me in a very odd and BAD place. I use this truck 7 days a week for work. It is my only work truck. The dealer told me the clutch was 3-4 days to order. Here I have the truck all torn down to make replacing the fan clutch a piece of cake. I was counting on the wisdom of the PBB and set aside half a day to clean out the rad and replace the tstat, but my instincts and diagnosis were correct. If I had the digi, I'd take a picture for you guys :flipoff2:

I was wheelin a new to me YJ and it started overheating a couple of miles in, pulled the clutch and dimpled the face with a screwdriver and hammer locking it up. Drove it 3 more weeks before it started slipping again. Bought a new one then. I'd dimple it, or drill and pin it untill your new one arrives.

I was wheelin a new to me YJ and it started overheating a couple of miles in, pulled the clutch and dimpled the face with a screwdriver and hammer locking it up. Drove it 3 more weeks before it started slipping again. Bought a new one then. I'd dimple it, or drill and pin it untill your new one arrives.

Is this the best way to lock it up? I would be willing to lock it up until things slow down for me a bit and I can afford to be or at least plan to be without my truck for a couple of days or at least a day

Does anyone make an electric fan for these? Something else, all the talk about a thermo clutch and needing air from the radiator to engage, there's a wire connection at the front/ center of the cluch, what does this do? NAPA also lists it as an electric clutch but cannot get it at this point, dealer only.

If I drill and pin the clutch with sheetmetal screws, do I run the risk of something breaking internally and causing more damage?

Does anyone make an electric fan for these? Something else, all the talk about a thermo clutch and needing air from the radiator to engage, there's a wire connection at the front/ center of the cluch, what does this do? NAPA also lists it as an electric clutch but cannot get it at this point, dealer only.



It is an electric, maybe all the 3rd gens are? The 600 certainly are. The ECM locks it.

You certainly have a clutch failure, you may have all the other problems too.

If it was my truck I would replace the clutch first, but these other suggestions maybe good ideas too.


I would stay away from electric fans, there is just so much CFM draw required for the big diesels, its hard to find one that would be big enough.

I couldn't find any on summit either. Since I had the coolers pulled, I pressure washed all of them. I have a new tstat and will change it out too. I'm going to call the dealer in the morning and have the clutch next day aired to me, so I can get back to work and just take a couple days off, since I worked all weekend. My truck is the 600 series motor, I thought I said HO?

What am I looking at to change the clutch, special tools, procedures? I've got the whole front of the rig opened up so access is the easy part.

My truck is the 600 series motor, I thought I said HO?

.

HO was the 555 model. Once the 600 was released there was no SO/HO desigination.

Ahh, with mine being an 04.5, I just use the HO

Does anyone make an electric fan for these? Something else, all the talk about a thermo clutch and needing air from the radiator to engage, there's a wire connection at the front/ center of the cluch, what does this do? NAPA also lists it as an electric clutch but cannot get it at this point, dealer only.

If I drill and pin the clutch with sheetmetal screws, do I run the risk of something breaking internally and causing more damage?


Dude, drill it and pin it.
Order a horton fan clutch and maybe there fan.
Plan a day when it is convienant to swap in, as you will have parts on hand.

Dude, drill it and pin it.
Order a horton fan clutch and maybe there fan.
Plan a day when it is convienant to swap in, as you will have parts on hand.

Who is a source for these parts? I've found nothing cooling related for the 600 series

Looks like you will have it figured out, but whatever you do, dont get those electric fans that many cummins and powerstroke guys were excited to get when they came out...the kit is $500, doesnt cool as well as a stock fan, and when the electric motors get hot, they have a shut off on them...not good when your $500 fans kick off and let your $8000 motor overheat.

Just got back from a dealer 45 min away that had one sitting on the shelf. My wife worked from home today, so I was able to take her car since the damn cruiser still isn't running. Will be back on the road in a couple of hours.

I totally disagree with the pressure wash suggestions here. Water under pressure will bend the fins flat and prevent air flow. Counterproductive to say the least. A fifty thousand mile radiator should be cherry inside, you do use distilled water and not that incredibly hard, mineral laden shit out of the garden hose, don't you??

Why yes I do, but can't speak for previous coolant that was added. I pulled about 11k up the hill today, floored with the A/C on hottest I saw was 207

That sounds more like a cummins temp to me :D

That sounds a whole lot like what my '01 runs with 10K in tow.