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Topic: Cooling system fan pump (Read 386 times) previous topic - next topic

Cooling system fan pump

What would cause the hydraulic pump to pulsate or gallop. Very pronounced when cold just after I start the engine. I tried to attach a video but it didn't work.
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Gerry & Brenda
CHARLOTTE HARBOR, FL
1994 Grand Villa - # 4466
U300 Unihome - 6V92 Detroit
4 speed Allison - Jake Brake

Re: Cooling system fan pump

Reply #1
Air, check the fluid level and suction side fittings. Just the first thing to check, I am sure that there are other possibilities
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
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2014 Grand Cherokee Overland
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Re: Cooling system fan pump

Reply #2
I agree with craneman. Not much to go wrong with a hydraulic pump besides leaking. Air would defiantly be an issue. The pumps self prime so would have to be low oil or maybe leak in suction hose??

Let us know what you find.

see ya
ken
The selected media item is not currently available.ken & dori hathaway & Big Agnes
🍺1992 U300 GrandVilla WTBI #4150 FOT FBP 2011
✨6V-92TA DDEC Parlor Coach 350HP Series 92
🏁2011 Nissan XTerra Pro-4X

Re: Cooling system fan pump

Reply #3
Not familiar with how the pump is driven on the 6V92, but if belt driven like on the other engines, we are assuming that the belt is OK and automatic belt tensioner is keeping the belt running smoothly.

If  the belt is jumping, it can also cause pressure to pulse.
Brett Wolfe
EX: 1993 U240
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