Fan Clutch or Radiator

[beretzs]

Alright, sorry I haven't posted in awhile, but the last time I drove the truck last weekend, I drove up some really big hills unloaded, which usually the truck flys up with no troubles at all. This time it got pretty warm, up in the 230* range. Then even once I got back down on flat ground it was still running a little warm. When I was heading up the hill, I had my windows down and could feel the coolant mist on my hand (not alot) but enough to notice. Well, after I finally got to flat ground it ran back to normal temps, but if I pushed it very hard, it would warm up quite a bit. Never really had a cooling problem, but I have one now. All the way going up those big hills, I cannot remember the fan clutch kicking on, clue number one. But then once I was on flat ground it was still running warm. Just for notes, it was about 75-80* outside, so that should not have been affecting it too much. I guess, I will have to do the fan clutch test, and maybe think about a new radiator too.

Anyhow, by the time I got to where I was going, I was about a gallon low on coolant, and I am thinking that it is because of the truck pushing all the extra into the coolant res and it overflowing. I was going to take it back up to the shop that did the headgaskets, but I am just wondering if it has anything to do with the headgaskets. I am kinda doubting it is the HG's since I have been running it fairly easily, not running over 1000* EGT, so I am thinking it has to be something with the cooling system. Radiator has alot of crap on the inside, not sure if it needs cleaning or what. I would rather just put a good 4-5 row radiator in there and be done with it. With all the extra power, I am not sure the stock radiator is up to the task of cooling the engine effieciently anymore.

So, if you guys have the link for the MS Tech Clutch fan, and good hookup for radiators, I would apprciate it. Oh, and on top of that struggle, I have a rear wheel seal leak. Gotta change them ASAP. This coolant thing has me bugged, the truck was running GREAT until I hit those big hills and it spilled coolant. Anyhow, any good feedback is really appreciated.

It does have the IH stat in there, just put a new one in when the HG's were done. So hopefully that is covered. Scotty

 

[jlayne]

if its overheating while your moving at any speed at all its not the fan clutch, they usually only cause a engine to run hot while sitting still because the fan isn't turning and the radiator doesn't have enough air flow over it... while you are driving there is enough air coming through the radiator you really don't even need a fan

 

[Mikes91]

I'm in the same boat, so please share radiator info when you settle on a brand/model.

I'm interested in going to a larger core number radiator, myself. I had some cooling issues on the trip to CA last year... hoping to fix those before the trip to SC in March. Pulling the same load again.



Mike

 

[RKOCH]

I have the largest core in mine and had the same problem. Guess what it was the fan clutch without the fan runing unless on the interstate it would do just that. And if I was pulling a large hill loaded at interstate speeds it would with out the fan. So yes for the most part you don't need the fan for normal driving speeds but loaded you better have it working.

 

[Agnem]

I really wish IH had not done away with the lower corner coolant passages in the 7.3. Those engines always seem much more prone to overheating than the 6.9's were.

 

[beretzs]

if its overheating while your moving at any speed at all its not the fan clutch, they usually only cause a engine to run hot while sitting still because the fan isn't turning and the radiator doesn't have enough air flow over it... while you are driving there is enough air coming through the radiator you really don't even need a fan

I don't know if it was really overheating per say.. It never got above 230* so I would think it was just warm, too warm, but still with in specs for the most part. The truck stayed in the 190-200* mark while traveling on flat ground, but just got too hot while pulling up hill. Still not sure where to start. Anybody know where the instructions are to test the fan clutch? Scotty

 

[hheynow]

Anybody know where the instructions are to test the fan clutch? Scotty

Not exactly a high tech method but with the truck off and cool, try to manually turn the fan. If it turns with resistance the clutch is good and as jlayne said, when at a red light if the temp needle doesn't keep rising to the red zone, it's working. Is it possible that your t-stat is sticking?

 

[beretzs]

I guess it is possible, but I just had a new one put in about a month ago. I will try the fan test and see what works. Hopefully it is just a fan clutch, I wanna put a better unit on it anyhow. Either way, the truck is taxing my patience right now. Scotty

 

[F350camper]

I have the largest core in mine and had the same problem. Guess what it was the fan clutch without the fan runing unless on the interstate it would do just that. And if I was pulling a large hill loaded at interstate speeds it would with out the fan. So yes for the most part you don't need the fan for normal driving speeds but loaded you better have it working.

Ditto, me too...

 

[gandalf]

Still not sure where to start. Anybody know where the instructions are to test the fan clutch? Scotty

Doesn't Pete (cdnsarguy, if my memory is right) have the instructions on his website?


Thats my recollection, anyway.

 

[beretzs]

I'll check it out.. Scotty

 

[Dambnicetruck]

I have the largest core in mine and had the same problem. Guess what it was the fan clutch without the fan runing unless on the interstate it would do just that. And if I was pulling a large hill loaded at interstate speeds it would with out the fan. So yes for the most part you don't need the fan for normal driving speeds but loaded you better have it working.

Yup, my truck is completely stock 7.3 turbo, and if loaded the fan comes on all time. The temp. here is about 90 right now, and I just drove the rockies. The fan came on about every 10 minutes, and would stay on on every hill and stay on for about 5 min. after the hill, shut down and come back on about 10 min. later. So it was definately dependent on the fan, even though I was doing at least 70 kmh mininum. I was loaded though with camper and boat on trailer, so I figure it did real good. It never went higher than the "M" in norMal on the gauge, so it never even came close to over heating. Fan worked alot though. Just curious, my fan comes on quiter early, at like the "N" in normal, and then turns off when the gauge drops to almost the line, then won't turn on again till it reaches the "N". This seems early to me, although the engine seems to be fine with it. The gauge goes quite high before it is red, and it has never even gone past the "M". Does this sound normal to you guys. You guys seem to run real hot, yet you say your fans hardly ever come on? Like I said, mine comes on all the time in hot weather, but never comes close to overheating. What do you think?

 

[RKOCH]

That is what it should do, come on and off maintaining the temp 10 min or so is fine.

 

[argve]

I was always taught to check the fan clutch was when it's cold it should be stiff then get the truck warm and it should free up but when it get HOT it should stiffen back up. At least that was the way I was always taught...

FWIW I never heard any of my fan clutches (OEM, aftermarket or modded) kick in but did see the action on the temp gauge with the modded clutch. If I could run her hard enough with the big rad and modded fan clutch once she hit 210 is was a race down.

 

[Darrin Tosh]

You guys seem to run real hot, yet you say your fans hardly ever come on? Like I said, mine comes on all the time in hot weather, but never comes close to overheating. What do you think?

It sounds like your fan works great, but you really don't know what your temp is using the NORMAL on the guage. Unless you install a real mechanical guage.

I just installed the MSTEC fan clutch, but I havent towed anything heavier than a Taurus Wagon with it yet. I will be hooking up the 29' 5th wheel in the next week or so to see if it will give me any inprovment in the overheating department. From what I have seen so far, it will.

If you are thinking about a new fan clutch, don't mess around with a stock one, spend the money and get the modified fan clutch from MS-Tec. It is about $250.00 shipped.