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hershey's avatar
hershey
Explorer
Jul 05, 2015

DP started overheating after a repair

2001 36' Fleetwood Expedition, 270 hp Cummin's and 5 spd Allison.
We are fulltimers, summer in WY and Winter in S CA. Last Nov just outside of Winslow AZ my radiator fan self destructed. Lost belts and fan pillow block. Repair facility had a hard time finding the correct parts and even the correct belts. After a week in their shop I was back on the road. Winter is cool but in May I found my first 90 degree weather on I-17 between Phoenix and Flagstaff. Started running a lot hotter than it has ever run.
I made it to Albuq with no real problem and thoroughly cleaned the radiator which I do as normal PM. BTW: Slobber tube is rerouted under radiator. Traded cars and now the new toad is 800 lbs heavier and traveling in 90+ temp, the MH still overheats on long grades.
My theory is: the repair facility replaced the fan with a different fan than the original and it isn't pulling enough air. I finally arrived at our summer destination and will do a more careful check of belt tention and number of blades on the replacement compared to the 9 blades on the old fan. I unhooked the toad on the last long grade today and it still overheats. I guess I'm looking for any other suggestions.
Class A

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  • robertbenita's avatar
    robertbenita
    Explorer
    Jul 05, 2015
    Properly burp the coolant system, thermostat, proper fan, fan not coming on at desired temperature... I would call them and seek their advice first. If that does not help, I would locate a reputable shop near where you are now. Good luck!
  • wolfe10's avatar
    wolfe10
    Explorer
    Jul 05, 2015
    Agree with the OP, first check is to verify that the fan is the correct one-- number of blades, pitch (i.e. CFM) AND that it was installed to PUSH air through the CAC and radiator. Have seen them installed backwards!

    My next step, assuming the thermostat is OE and therefore 14-15 years old, would be to replace the thermostat.
  • Ivylog's avatar
    Ivylog
    Explorer III
    Jul 05, 2015
    Dennis, wouldn't taking the radiator cap off of the expansion tank do the same thing? I've never seen a DP with the cap on the top of the radiator.
  • Executive45's avatar
    Executive45
    Explorer III
    Jul 05, 2015
    What you describe is classic air bubble. There are a number of ways to clear the air bubble. I found the easiest is to use one of the fillers below. Then again, if there's a warranty type thing involved, let them do it. Assuming you used a nationwide facility. If not, and you're going to do it yourself, invest in the item below. You'll be happy you did...Easy to use, attach it in place of your radiator cap and start your engine. Fill the funnel as needed and let the air bleed out of the system...Done....Dennis

    Lisle Spill Free Coolant Funnel
  • hershey's avatar
    hershey
    Explorer
    Jul 05, 2015
    donn0128 wrote:
    My first guess is an air bubble in the system. If they did not follow proper burping procedures it is possible.......
    Tnx. Would it self burp in the 2000 miles I've put on since the repair? I've added just over a gallon of fluid since the repair to the system thru the radiator bottle view.
    On edit. The system was drained and radiator hoses replaced during the repair. I did notice that the temp raises and lowers perhaps 5 to 10 degrees very rapidly during the warmup period. I don't remember that happening before the repairs. Maybe we;re on to something.
  • donn0128's avatar
    donn0128
    Explorer II
    Jul 05, 2015
    My first guess is an air bubble in the system. If they did not follow proper burping procedures it is possible.......

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