Pontoon Boat & Deck Boat Forum

The last couple of times we were out, I had a fuel delivery problem. Original tank is 20 gal and I cleaned it completely out during the re-build. It has two straws into the tank, one long reserve and one shorter main connected to a valve. Main pulls fuel down to 15 gallons and Reserve pulls the remaining 5 gal. After an hour of troubleshooting, I think the straws(pickup tubes in tank) are compromised and sucking 50% air.

So here is the dilema on a 33 year old tank. The fittings are really stuck and it appears to be zinc or galvanized...any wrench pressure on them to unscrew makes the tank top distort. If I reef on it I know its going to crack or shatter. Any ideas or do I just siphon all the old gas out and go for it, then replace the tank?

I got one of the pickup tubes out, the insert did not spin so I know I am lucky. The tube is milky white plastic - intact, and has a small screen at the bottom. Both the tank and the screen are clean/clear so I am stumped. I moved the fuel line pump ball from being between the Racor filter and the engine to being between the Racor and the fuel tank....no change. I still cannot get any fuel into the Racor(which I removed and dumped the fuel out) by pumping the ball. Hell, I can barely get fuel to pump into an open container. I even bypassed the 'Reserve/main' valve and connected right to the pick up tube. I am using two different one year old outboard lines with pump ball and both are in excellent shape. I verified that the tank vent is working & un-obstructed.

Both filters on the Honda 115 EFI 4 stroke look clean but I am going to change them and the Racor anyway. When we were on the lake the other day and it would not start, I had a buddy pump the ball while I hit the ignition. After several tries the engine started and ran fine after the engine fuel pump took over. Even if the fuel pump was weak, it does not explain why I cannot manually pump fuel up from the tank to the Racor. I have no idea of what to try next........

I'm wondering if there is corrosion inside the zinc/galvanized fitting at the top (outside) of the tank.

steve1313 wrote: ↑

Mon Aug 02, 2021 3:13 am

I'm wondering if there is corrosion inside the zinc/galvanized fitting at the top (outside) of the tank.

I' going to replace both pickups with stainless steel ones. Now....down my rabbit hole of R&R I have read that Modern 4 stroke EFI engines should not use an external filter. My Honda does have two filters on the engine, a water trap and a paper one so maybe I should ditch the Racor? My last 'toon had a Yami 90 on it and no external filter....never a fuel problem for 4 years of use. I have also read that a pump ball is not even necessary because the engine fuel pump does all the work. I am really starting to feel like a dinosaur right now........

Is your pump an Atwood? Grey one from Walmart or other box store? If so There where a ton of fake Chinese ones several years ago and people are still finding them, my boat came with on and found info online about them being faulty. The glue separates the pcs, some say it is caused from ethanol, might check it

I had an attwood fuel line bought last year and it drained an entire tank of gas overnight. Went with oem and no more leaks. I'd try changing the fuel hose first. If that doesn't fix it then I'd replace the whole tank. Sounds like you have a nice engine don't want any crud coming from disentagrating fittings or plastic tubes.

I was just reading about the fuel hose/bulb disintegration issue...looking at my hoses now & thanks for the tip.

Did you put the square pick up fitting back in? I think that may be an anti-siphon valve which can go bad and cut fuel flow. See if you can see a little ball and spring in it when you take it out. They're meant to keep a cut hose being able to fill the bilge up with fuel so if that is indeed an anti-siphon valve I wouldn't see a problem removing it if your tank is exposed like on a pontoon and your fuel lines are above the tank.

I bet you’ll find that it's ethanol damage to the inside of your fuel lines.

I’ve never had a fourstroke outboard setup that didn’t include a separate fuel filter/water separator, so I’d definitely be keeping the Racor if it was my boat…

Update:

It's been awhile, but I did replace the pickup tubes on the fuel tank. Old ones were crumbling. I still had issues with stalling out at idle which continued to be an intermittent problem. Finally talked to one of the local mechanics who asked what brand of primer bulb ball was on it.....it's and automotive store purchase and was new with the re-build. He said throw it away and put a Mercury ball on it, they are the ONLY one's the dealership uses, because they have had trouble with all other brands. They are not even a Mercury dealer. What the heck, I bought one and installed it.....humph....no more stalling.

Nice!

Well sports fans, I'm back with the fuel delivery problem. Ran the boat a couple of months ago after new fuel lines, new Merc primer bulb, and filters cleaned....ran flawless all day, which was a tank and a half/30gal.

Last time out, idled fine out of the marina, then coughed and stalled after a short 4100rpm run. After that, the primer ball keep going empty and required a SIL to stand there and pump it. Engine was erratic at idle, but after some time pumping, we could get it going fine at a higher rpm. Local Honda service guy says to go get a remote fuel tank, ball, and hose and hook it direct to the engine and test it. So that's what I did (Idles and revs up fine on the water ears, it needs a lake test), but in the meantime I ordered some new hoses in the engine compartment that are cracking, & all new fuel filters. I will be looking at the check valves on the tank straws too.

But, let me show you Honda's fuel nipple on the engine....it's not a consistent diameter, it's actually shaped like a nipple, and it's a 1/4 inch fitting. Everything else from the tank is 3/8th's which makes attaching a fuel line to the engine a pain in the .....


All other fuel fittings on the engine are standard barbs....



^new grey hoses above are on the way

I had to sleeve it to get a tight fit to engine & it works, but for something more permanent I am going to come off the engine with a 1/4" hose, then to a brass barb adapter from 1/4 to 3/8ths, then to tank.

cracked fuel line:

i hate fuel issues. Sounds like you're on the right path.