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engine fan kicks on early,and won't shut off at all if a/c is on


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I had to break down and bring my truck to my local mack/volvo dealer,the radiator blew,first I was told sure, we can fix it,3 days later it was no its junk,you need a new one, 4000 bucks and 12 weeks ahh no. so they get one from a junkyard and that's fine by me. only now there is no tranny cooler, it has an 18 speed mack tranny, and for some unknown reason the engine fan kicks on at about 120 degrees,doesn't shut of until it finally reaches 180. then if the a/c is on the fan kicks on and will not shut off unless you shut the a/c off.it has a junky horton fan that chirps like mad,that they were also told to fix,and didn't. the fan worked normal,aside from the chirping,prior to going there. so if some one can point me in the right direction as to what cooler i'll need and where to get it i'm all ears.also if theres a sensor or something for the fan to check,i tried bypassing the air/electric cut off switch but that didn't stop it either.it's a e-7 427 1995 engine. or is there a better option for a fan for it. i get no where with the dealer here they apparenly are only interested in selling volvo and severely over priced parts that they don't stock. the one (and i use this term loosely) tech told me flat out if it's not a volvo and new enough to where i can't plug in to it i have no clue how to fix it. are you kidding me. so i'll fix it myself,with hopefully some more great input from you people.

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Ron is the trans cooler in the bottom tank of the old rad.? will the tank swap with wrecking yard rad.? I'm not sure what changed the fan clutch temps, bad ground perhaps? did the dealer change any senders? possible wrong or mispackaged sender?

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yes the cooler was in the bottom of old radiator.and no they couldn't make it fit this other radiator they said. every sensor on the engine has been replaced new. i had no choice but to run the truck today,as much as i'd rather not have. i'm pretty certain the fan is playing a big part, it chirps and squeals like mad.they told me it was fine. no way. i stayed on the flatlands today, and truck was hot ran 220 /235 best it cooled to was 200 the thermostat is also new. i was told by a tech from the k/w shop that as long as my cooler lines are together so the pump can circulate i should be fine, i'm hoping that's correct

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the fan noise sounds like they either have loose belts, glazed belts or antifreeze covered belts if the fan runs at low temp and squeals. shut the eng off while fan is running, then turn key to the run position this should engage the fan clutch then grab the fan blade and see where the belt slips at. if belts are glazed some steel wool or wire brush should break the glaze if its anti freeze try rubbing alcohol. i'm not sure when you said truck ran hot today was the fan running? do you have a manual fan sw. does it work? is fan properly installed? is fan shroud in place?

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prior to the original radiator failure,the fan would on occasion squeal, my first thought was belts,and they are tight,they don't appear "shiny"like they've been slipping,they look pretty good no cracks or like chaffing on edges. after mack put the used radiator in the truck the truck runs hot,it always ran at 180/185 and would reach maybe 200 pulling a heavy box up a long hill. now truck runs at 225/230 and if you even think about goin uphill empty even it's at 250. the shroud is on it and i do have a manual fan switch. i don't need to use it because the fan now is almost never off. every sensor on it has been replaced new. i'm not losing coolant or gaining oil, just putting that out there. i'm kinda starting to feel like i got a junkyard radiator that was full of stop leak, or my water pump is bad maybe? i don't have the dimensions of the original radiator to compare to this one,maybe it's just not big enough,mack changed all the brackets and mounts to put it in, i would like to think they would know whether it would work correctly

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I'd be on the phone with the wrecking yard and the dealer at 250 degrees your gonna need more than a rad. soon it will be heads, pistons and liners the wrecking yard should of had it flow tested if not the dealer should have. get a inferred heat gun and shoot inlet and outlet rad. temps should get a 60 degree drop + or - also is the FAN INSTALLED RIGHT? wouldn't be the first time I've seen this done.

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put the truck in our shop,dark and put a light in between the charge air cooler and radiator and guess what.. plugged no light comes thru a good portion of radiator. angry doesn't even describe it. after some pestering i found out that they picked up the radiator, didn't look at it just threw it back together,swell, so the good news is i'm getting a new fan,a new water pump, because the bearing is loose now, the radiator is getting boiled and tested the k/w dealer is doin it and mack is paying for it. glad i only used the truck a little,wouldn't have thought they would put it in as is. so thank you guy's for the replies, and an infrared gun is definitely going to be in the toolbox now

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We use our KW dealer for anything to big for us to handle on our own since we have dont have nice fancy lifts and all that stuff. Its pretty sad whn you go there and theres a bunch of new Macks getting worked on cause our big mack dealer in the state dont have a clue what they're doing. The family owned mack dealer on the other hand does very good work. Says something dont it.....

Matt

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yeah it sure does, at one time there was 3 dealers in my town, now there is one, they don't seem to care at all,and it's sad because there is a lot of mack truck fleets in my area. some of the "big money" fleets around here have switched from k/w to volvo and it seems they are more interested in oil change and service for them. but that's how it goes i guess

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ain't it wonderful when people would rather text and screw off instead of pay attention to what the hell they are doing, removing a plugged rad and replacing with a more plugged rad. unflippin believable! did they have the janitor do the work. that store manager needs a ear full!

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I have to say our Mack dealer McDevitt up here does a good job, have sent our trucks there when we cant do the work our selves do to time or just to much for our mechanics. The last time I got parts for my Superliner the younger parts guy was having a hard time finding the switch I needed he asked the older parts guy who walked out back and pulled out as he called it his black book and quickly found the part in his book not the computer and then crossed the number over to new number, Guys like that are fewer on the older trucks everywhere.

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