Video of generator fuel primer pump in "action"

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Dune

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Viking 65 CP MY (run at trawler speeds !)
I hope these are supposed to be more powerful than this ! This direct to gallon of diesel. Generator is Onan 4ml. 1993 year 20Kw. So is this dribble flow normal or weak ?

If normal, then I have blockage at pickup tube because *nothing* will come out when the hoses are connected properly and in/out valves open.

Cannot find a manuf name or model on pump to save my life... about 4" dia x 5" long

(Any chance the primer pump has to be primed ??)


 
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I have a MDL3 14kw. The fuel circuit is a lift pump and the injector pump. No primer pump and no idea what it would be used for. Is this a transfer pump?
Pump could be sucking air from a leaking fitting, hole worn in the fuel line, loose filter, etc. It's easier to draw air than fuel.
 
Does it look like this?
 

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Yes ! That's exactly it. They still in business ? (Whoever they is)

But more importantly, what is your opinion of my flow video ..is that normal flow or almost normal or way off ?

Thanks !
 
Not normal. Either pump is pooped, supply blocked, or air leaking in. Try connecting pump to an alternate source of fuel (jug) and see how it works.
 
Look closer at the video... the "in" line is almost totally immersed in a near full gallon jug of diesel..

So, is is *very*. weak flow or just a little weak ?

Also can anyone here identify the pump manuf or say if it might be dissassembled and cleaned inside or if it likely has rubber or pplastic impeller that is shot ?
 
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Not normal. Either pump is pooped, supply blocked, or air leaking in. Try connecting pump to an alternate source of fuel (jug) and see how it works.

What Ski said.

I seem to recall those pumps had an internal screen. But I could be wrong.

It's a Welbro pumps. That model is discontinued but you can find them on eBay.
 
I think Capt Bill is right. It was made by Walbro but it was also sold as Stewart Warner.
 
It looks to me like it's pumping a bunch of air. How much hose was between it and that gallon of fuel? You didn't run it very long. Maybe the lines are full of air.

Ken
 
That stream would worry a urologist. That it "flows" as the vid shows, and not at all when the tubes are connected creating resistance to flow, suggests inadequate pump pressure. I doubt you have much to lose by trying to get inside the pump but make sure a replacement exists before being too aggressive with it.
 
It looks to me like it's pumping a bunch of air. How much hose was between it and that gallon of fuel? You didn't run it very long. Maybe the lines are full of air.

Ken
X2
 
Today I did same experiment with the generator no2 pump and its flow was waaaaaay better, absolute confirmation that pump 1 is kaput
 

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