79 Grady Fisherman gas issues

[1fullstringer]

All,
I recently bought a 20' 79 Grady fisherman. I have been working on it and its 150 suzuki. It ran great until i put new gas in it (I know same story as usual!). After replacing all the fuel lines and primer ball, etc. I cant get the proper vacuum in order to allow proper flow of fuel to the primer. This is what I've done to try to troubleshoot the problem:

Disconnect the fuel line from the tank.... primer ball immediately filled up
disconnected the vent line from tank....nothing changed
removed the gas supply tube and inspected for sediment or blockage....nothing noticeable
treated gas with startron

Motor runs but ball will collapse and gas will trickle in. Gas looks clear, filter still looks good.

Any ideas? I have my suspicions about sediment in the gas or the supply tube.
Any easy way to drain the gas and inspect?

You replies are appreciated.

-Aaron

[Grady23]

How "old" iwas the gas in the tank before you added anything? Did the old gas in the tank have the BFTE in it?? If so, the gas has become contaminated with tiny globs of gunk that will look like rice. If the gas is low eneough, down about a 1/4 tank or so, you can remove the sending unit and take a sample of gas from the bottom of the tank. Just use a oiece of tubing cut about 24-26" long and insert it into the tank to the bottom. Once on the bottom, just put your thumb over the open end of the tube and then hold it there while you pull the tube out. Dump the sample in to a clear container where you can inspect it. You may also be able to inspect the pick-up tube and screen in the tank depending on how the tank is constructed.
PS -- Please --- DON"T use an electric/cordless drill when removing the screws for the sending unit --
Sparks from the drill could be a PROBLEM!!.

BTW--- IS the tank aluminum or fiberglass?? If it's fiberglass, you will need to replace it with an aluminum tank because of the ethanol.

[rj]

You didn't mention the anti siphon valve,
did you check it? it could be stuck or clogged

you mentioned "gas supply tube" do you mean the pickup tube in the tank,,many of them have a screen on the end of them,
is the tube clear?

to drain tank, just route fuel hose overboard into a suitable container & use primer to start fuel flow, it will siphon out

[1fullstringer]

The tank is aluminum and I did remove and inspect the pick up tube. I saw no screen but there is a ball bearing type of assembly in it. The tube is aluminum also.

Thanks for your input.
-Aaron

[Fishing-Rod]

Try changing your anti-siphon valve at the tank, it's a $12 part and solved my problems.

I had very similar symptoms on my 225 OX66, it started out with burps then progressed to shutting down the engine. It would start right back up again, so I kept my hatch open and saw that every time it burped, or shut down the engine the bulb would collapse... telling me it couldn't get any fuel. So I replaced the fuel filter, tank vent (in case a spider made a home in it) but the problem just got worse. So finally after doing some searching/research on TidalFish and The Hull Truth I changed the anti-siphon valve and everything ran great. 4 years ago I had E10 fuel problems and had the fuel hoses replaced, fuel tank cleaned, etc. The only thing I didn't do was replace the anti-siphon valve, hindsight now being 20/20

Thanks, Fishing-Rod

[Wingnutt01]

will collapse and gas will trickle in

Yup, I agree with the others, anti-siphon valve or possibly the fuel tank vent itself. Keep us updated.

[1fullstringer]

Thanks guys,
I'll try to sample the gas straight from the tank. If it is clear I will swap out the anti siphon valve. I'll let you know when I figure it out.

-Aaron

[Halfshot]

I hooked my fuel line to an external tank that I knew was good and ran the boat...showed me if the tank was the problem, it was, and I had the same symptons as you do...good luck

[1fullstringer]

Half shot..
What did you do to fix/ clean the tank?

-Aaron

[Halfshot]

I still have to cut the floor out, remove the tank and clean or replace, then glass the floor back in....CAN'T WAIT!