edalegsd
Tofield, AB
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Joined: 07/12/2009
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Hi Guys / Gals
Thought I would share with you a fix to a thorn in my side for the past few years.
1994 GulfStream Sunvoyager 32ft Cummins engine.
Motors great if the air temp outside was 75F or cooler, had high temp issues on hills and couldn't climb any large hills without "High Temp" alarm, We had flushed the Rad, hosed out the Rad - even installed "Air Channels" to the engine.
A cummins guy camping with my Son in Law had a quick look -
THE RAD FAN WAS ON BACKWARDS !!!
To look at it - seemed ok the air was being pushed toward the Rad as it should, but placed the otherway - it "Scoops" the air and forces it toward the Rad - Huge difference !!
No we had not taken the fan off at anytime - previous owner.
Such a relief now !
Stu
1994 Gulf Stream Money Pit ( Sun Voyager )
B 5.9 Cummins 6 sp Allison Tr
Stuart & Sharon & way too many German Shepherds ;-)
Tofield, Alberta Canada
www.edalegsd.com
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wolfe10
Texas
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Joined: 10/08/2000
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Not sure I am completely clear on what you are describing, but, the fan pulls in air from the front and forces it through the CAC (Charge Air Cooler) and radiator before it exits the back of the coach.
If the blade is installed backwards, it would pull air from the back and try to push it to the front-- WRONG.
If you can feel good strong air flow when standing behind the coach, all is well.
DO check the front of the CAC for dirt buildup around the perimeter with a strong flashlight. Access from the bedroom or closet and look inside the fan shroud/between fan blades.
Brett Wolfe
1993 Foretravel 36' U-240
Cat 3116, Allison 3060
FMCA Forum: www.community.fmca.com/index
Caterpillar RV Engine Owner's Club: www.catrvclub.org
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wny_pat
Western NYS
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Joined: 08/11/2007
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I'm with Brett, want to hear more about this before you go pulling the fan off!
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Snowwing
WA
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Joined: 11/30/2004
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It makes no difference to air flow direction if the fan is "reversed". To change air flow direction you would need a different fan. Right hand versus left hand blades.
Spacing could possibly be incorrect but not direction of flow.
Ron
2005 Journey 36G
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SpinRite
Research Triangle, NC
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Joined: 07/17/2006
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Agree with 'Snowwing' - if you put the fan blade on backwards, it still pushes air the same direction!
It's contra-intuitive, but think about it awhile. (You can win money in a bar with this one!)
Perhaps the difference was simply that the leading- and trailing-edges of the blade were backwards, making for less efficient airflow.
Maybe the OP can clarify this, since he seemed to feel that some real change had been effected by reversing the blade.
'94 Holiday Rambler Navigator
38', Cummins 8.3 300hp, Allison 3060
pushed by a 2005 Honda Element
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edalegsd
Tofield, AB
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Hi again
Good discussion. I would agree that reversing the blade should not change - if the blade was a straight edge - my recollection was that the blades are like a plane propellor. Like the Cummins guy stated "it scoops the air- not pushes" so more efficient airflow.
My Son-in-Law has not returned from BC ( currently over 90 Deg F )
and is pulling his 20' skiboat back to give it a good test. I'll let you know how it goes in a couple of days.
Stu
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rgatijnet1
Florida
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Joined: 06/22/2009
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For those that wonder about reversing the flow of an electric fan, you may want to read these instructions that are given with this fan:
Summit Radiator fan, reversible
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Turbo Diesel Dude
Green Mountain, NC
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I'd steam clean BETWEEN the radiators fins and charger. May have a grease buildup as my BIL had once. Cleaned it that way and overheat problem went away. Fan couldn't have been reversed for that long and no problems. JMHO. "I thought I was wrong once, but found out I was just mistaken".
charles weidman
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Triker33
Homestead, FL
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Joined: 11/30/2002
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Heat problem happens a lot on the older 5.9L that never have had a slobber tube extension put on.
Or the CAC hasn't been cleaned on a regular maintenance schedule.
Larry Full Time Since 99
1999 34Q Discovery DP ISB 275HP 6 Speed Allison
Banks Powerpack
DataStorm SatMax5 | VMSpc | Pressure Pro
08 HHR LT2
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edalegsd
Tofield, AB
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Hi again,
We had the RAD off last year as there was a leak at the sweat joint for the outlet hose coupler, already steam cleaned the whole rad etc. flushed the coolant a couple of times. It has always had issues getting hot on hills - but never if the air temperature was cool. The cummins 5.9 does not have the same "Breather" issues as CAT, no oil residue issues.
I have had this unit on the road for 3 years since we got it and restored it.
The air flow before the fan was reversed seemed ok, revving the engine without the access hatch locked - the air flow was sufficient to move the hatch.
My Son-in-Law says he stood back there with the fan reversed and he is very impressed with the increased air flow.
I'm not suggesting everyone run out and reverse the fans - the previous owners/service done must have done this. Spacers for the fan to avoid catching the AC or Alt' were required - Cummins guy said that's why they must have put it on backwards as they were missing and it missed the AC and Alt that way.
Stu
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