Bleed fuel with no fuel in fuel water seperator

Cutwater28GG

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Cutwater 28
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I just changed filters and forgot to prefill the fuel water seperator with fuel. Can I prime and bleed the fuel through this filter through the normal method of cracking the bleed nut and pumping manually? Or do I need some fuel in the filter to build pressure to prime?

Volvo d260.
 
I just changed filters and forgot to prefill the fuel water seperator with fuel. Can I prime and bleed the fuel through this filter through the normal method of cracking the bleed nut and pumping manually? Or do I need some fuel in the filter to build pressure to prime?

Volvo d260.
I literally just did this work 3 days ago. I deliberately did not put any diesel in the water separator when replacing because I was told that by VP mechanic whose opinion I totally respect.
Yes, you open the bleed valve until it almost comes completely out and hand pump. And pump. And pump. Very little pumping resistance with the air coming out so it’s easy. Eventually you will get diesel and air bubbles coming out. When you don’t have any air in the fuel coming out you are ready to close the bleed nut.
 
Thank you!!!
 
Are we taking 500 or 5000 pump presses?
 
Are we taking 500 or 5000 pump presses?
As I remember it was 25-40 pumps. About 2 minutes of solid pumping. But make sure the clear plastic cap is off and the bleed nut is fully open. If not you will pump forever without results. A bit of tubing on the end of the bleed nut stuck in some liquid should show air bubbles when you pump.
 
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What plastic cap are you referring to?

IMG_9522.jpeg
 
Right where your finger is pointing I have a clear plastic cap that fits over the barbed hose attachment ( aka image.jpgdraining side) end of the bleed valve. To keep dirt out of the bleed valve I assume.
 
Also FYI - 1/4 inch ID hose with a small plastic bucket is much cleaner than trying to hold a crushed solo-cup under the nipple. I also never prefill, but only upgraded to using a hose this year, it's so much less stressful worry about spilling fuel
 
thank you.
After pumping 1000s of times. I removed the separator and there was no fuel in it. so I prefilled and tried again. Again, no bleeding.

After searching the internet, it's a known problem. The bleed valve gets stuck inside the pump. A few taps on the black button got it loosened. Primed in 5 pumps - yay. You can tell if the valve is stuck, as you can hear the same air move both ways when pressing the pump. once it's unstuck, you only get air on the press and not the retract.
 
Assuming you turned off the fuel line valve to the filters before starting, I put an 18" length of clear tubing (aquarium air hose works fine) on the nipple on the bleed valve after I put the correct box wrench on the bleed valve in a position to allow as much turn as is allowed without having to reposition the wrench. I then tape a clear bottle to the wall or bulkhead or anything stationary close by and put the hose in the bottle. One hand on the wrench and the other pumping. Bottle can't get away or tip. Open valve as far as the wrench will allow and pump to prime. You will be able to see when there is a good flow. Since a small amount of air will leak back in around the bleed valve threads, on the last 3 or 4 strokes I pump, close valve before letting plunger up, open valve with pressure in the primer, close and repeat till no more air is seen.
My manual says to NOT fill filter before installing since this fuel being put in the filter bowl is not filtered. I can fill the primary and secondary filter at the same time this way also, since there is not a bleeder or primer on the primary. Probably 20 strokes to fill both. Using the correct box wrench makes it much less likely you will round off the shoulders on the bleed valve. Some prime pumps are a little different, but the principal is the same.
(Learned the hard way that if you forget to turn on the fuel valve from the tank after changing filters then no method works. LOL!)
I am also a believer in putting a thin film of grease on the gasket before screwing on the filter.
 
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