Head - Intermittent Back Pressure on W/C Skipper II

[pma_foyl]

Hi There,
I'm having an intermittent problem where my Wilcox-Crittenden Skipper II head becomes VERY hard to pump. Sometimes it feels like it's close to immobile. I believe it is experiencing some is some kind of pressure build-up, because I can see bubbles coming back into the bowl water in the tank (when I stop pumping). Then, at some point, the pressure will relieve and it will pump perfectly.

Of course, it will happen again in the not too distant future. I also sometime see minor backflow into the bowl. I can't figure it out and I'm concerned it will ultimately fail while I'm far from home (of course).

Could it be a weird vapor-lock somewhere? Occluded output hoses? I'm pretty sure I don't have anything in my intake (because the problem is felt both with the intake pedal pressed and with it NOT engaged).

I'm sure this is not the first time this has occurred... just the first time for me and I'm baffled.

Any assistance would be greatly appreciated.
Thanks,

Paul
Talisman

[HopCar]

Are you pumping into a holding tank?
If so, check the vent on the tank. A blocked vent could cause what you're describing.

[Cowboy Sailer]

I had a Y valve that was not moving all the way and it would create a blockage that would later melt and it would seem ok. Replacing the Y valve fixed it.

[pma_foyl]

Hi HopCar - I'm having the problem going to sea (not to holding tank).

Jerry, I will check the Y-valve.

Thank you both.

Any other thoughts.