Anti-syphon valve ?????

[brianct12]

Guys,
Might anyone know - *do these V20's use an anti-syphon valve on the fuel tank ??? *

I just picked up another V20 - *1986 cuddy - *with a 2003 150 Johnson. * I am having a problem with the primer bulb going soft and the engine not getting gas. *Motor will stall out. * If I go back and pump the bulb up tight, *the motor will run fine again. * I have replaced the fuel line from the tank, added a new bulb and new fuel filter assy. *Still the same problem. *I am suspecting a fuel pump problem with the engine. * *Anyhow, after surfing the websites about this problem - *may people talk about an anti-syphon valve on the fuel tank maybe causing a probelm.

This 1986 has an aluminum tank and there is a shut-off ball valve at the tank fitting which the 3/8" fuel line connects to. * My 1988 plastic tank had no shut-off valve on the fitting. * On either tank - *I cant see anything that looks like an anti-syphon valve ?? * * * Thanks for any advice. *Brian

[macojoe]

The anti-syphon valve is in the top of the tank fitting that the hose connects to.

The pick up hose comes out the tank then you have a square like fitting that the hose to the motor goes to. In that square fitting is the ball.

I removed mine long ago!! Might be all gunked up?? But I bet you go back to the fuel pump when you are done.

Things to ck

Vents need to be clear!! or they will stop the flow!!

sock on the pick up in the tank, get cloged and no gas

the anti-syphon valve

filter?? This new gas is cloging all the filters!!

the primer ball its self

the filter on the motor??

little O rings on the gas line connector

and last the fuel pump.


The quickest way to find out if it is fuel pump is to run a 6 gal tank with a different hose.

If it runs good then look at all the stuff above, if still no run then look at the fuel pump!!

[phatdaddy]

Next time it starts to go dead, open the fill cap and see if that helps, if it does, its the vent

[brianct12]

Thanks for the advice. * I will run the motor off a 6 gal tank soon to bypass the main tank - *see what happens. * It wont be tomorrow though. * Yesterday when I was backing the truck (96 F150) down the ramp to retrieve - *the brake pedal went to the floor * *:o * Talk about jump starting your heart !! * A FINE TIME for a brake line leak !

Dang - *I just had the tank cover off - *but re-installed it with silicone caulk. *If I had known where the anti-syphon valve was I would have removed it *!! * *For those who are curious - *here are a few pics of an '86 tank, close-up of the fuel pickup fitting, and tank label.

[macojoe]

The square thing before the shut off is were your CK is!!

[msbhammer]

Its the GAS, I filled up my car yesturday at the WAWA because its the cheapest gas around, $2.99 .
Made it about 50 miles then the car broke down. Ideled fine, but would not go anywhere when excelerating. Would just boog out. Had to replace the fuel filter ! :-/

[turbinedoctor]

I am having a similar problem. My motor starts and runs fine for hours but when I shut it off I have to pump the primer bulb to fill the carbs and get it to start, once running no problem. I was told that it could be vapor locking as the 1984 90hp merc does not have much air flow to cool the surrounds of the engine. Let me know how your repairs go or does anyone have my type of problem.

[axespino]

When I had my saddle tanks I would have a problem after half of the tank was empty. It turned out that the boat sat for a long time with half a tank of gas and the dip tube above the gas line became pitted with holes and when I got below that point it started to suck air. I put a temporary tank and it ran fine so I plugged the dip tube at the top of the tank and had some fittings welded 1" from the bottom for my suction hoses. No problems after that

[brianct12]

Fixed !!!!!! I ran the boat on a 6-gal tank and still had the same problem. So, I bit the bullet and bought a new fuel pump ($220 !). Installed this weekend and test ran her. Problem solved. Idled for 30 min straight and then took right off when I gave her gas. No more stalling or having to pump the bulb. Can you imagine - the motor (a 2003) was put on new last season and had less than 100 hrs. The previous owner mentioned he had this problem from the get-go. He shoulda had it fixed under warranty ! I'd like to repair the old pump. Might anyone know where I can pick up a VRO re-build kit for this motor ??? I heard OMC used to sell kits for rebuild - but that Bombardier might not any longer. Supposedly, its the rubber diaphragm in the pump that goes bad. Its highway robbery to buy a whole new pump when you could just replace the diaphragm.

[shicks007]

BCT,

This guy was alot of help when I had fuel pump issues with my old motor.


http://maxrules.com/fixomcvro.html

Good luck,
Scott