Intermittent fuel issue and Ventilation

[FingerLaker]

Hi all, my 89' Maxum with a 3.0 Mercruiser, that I use not nearly enough (the source of most problems, likely) has run fine for me in my third year with it (previous owner was the town mechanic!), but occasionally, with no consistency, except possibly after a long run time before incidence, just bogs and dies like its out of fuel. 15-30 mins of floating and fishing and it restarts normally. Then its fine, but mostly, of course I tend to head in after that or move to the troller. But its always ran long enough again to get me back to ramp. NOW, this year I was fuelling up for the first time with only about 3-4 gals left in since October; gas spilled back out port after only a couple gallons, and also stuff started spilling out from the tank ventilator thing, with some sort of residue; I figured it pushed most out, but I still had it later when trying to add just a few more gallons. The boat was stored in an open field.

SO: Could this be related to my intermittent fuel supply problem that resolves itself..?! i.e., does ventilation also effect fuel supply to the lines- and how does one thoroughly clean the ventilator thingy to make sure it breathes well and doesn't clog? I am away from the boat again, so I duck taped the ventilator in the meanwhile to keep critters out.

Thanks for any insights any might have.
FingerLaker
'87 Bayliner Capri/85 H.P. Force on the Big Muddy Potomac
'89 Maxum 1900SR/Mercruiser 3.0 on Cayuga's Shining Waters (NY)

 

[alldodge]

Sounds like your drawing a vacuum on the tank. The tank vent line is clogged or the vent it self. Disconnect the vent line from the tank and blow thru it

 

[FingerLaker]

OH, wow, thanks, alldodge..! Didn't know you could do that... I'll have to look up some diagrams to see where that connection even is.. I've never done anything with the tank. Replaced my blower is the furthest down in there I've been..

Thanks for your quick reply.

 

[alldodge]

The vent is either part of the cap or right next to it

 

[FingerLaker]

Hey, this is great, alldodge! Thanks again. Actually, mine has the cowl and is located on the opposite side of the outdrive but on the high side. this is very helpful, but I'll also check to see if the Maxum manual has any tips about where the tank side would be so I can try some compressed air through that end. Thanks again, and Happy Boating!

 

[alldodge]

If you use compressed air do remove the gas cap. Tanks should not have any more then 3 psi. You can you 90 psi so long as the cap has been removed

 

[FingerLaker]

OH! That's good to know. Thanks so much again, Alldodge!!