HELP! Fuel issues crushing primer bulb under vacuum

[Shrek]

Sorry for the long post, but please bear with me. I could sure use the help of the brain trust.

My boat is new to me. The boat sat up high and dry for an unknown length of time before I bought it. I filled the aluminum tank with 40 gallons of new fuel and promptly had significant fuel issues, including pulling a vacuum on the primer bulb.

The first time I ran the boat, I could not even get onto plane before I crushed the primer bulb under vacuum. I burped the primer bulb and the boat restarted but the same thing kept happening over and over again. Vent line clear and functioning. Opening the fuel fill did not burp the system. There is no check valve in the supply line at the tank. Limped back to the dock at idle with periodic burps to the primer bulb necessary.

When I got home I replaced the fuel filter which was full of varnishy looking flakes and a bit of water. I pulled the sender and siphoned about 7 gallons out of the tank and tried to siphon out all of the particulate matter that I could see. Ran the boat again and while it did not pull a vacuum on the bulb, the motor would not rev out.

Took the boat home again and replaced the filter again, put a spare filter on the boat, put in more fresh gas and tried it again. This time, I ran through 15 gallons with no problems, motor ran great and reved out with no problems. At gallon 16, the boat began surging with the surging getting worse as I ran. I changed out the fuel filter for the spare while on the water (old filter had gas the color of mud and large particulate matter settled out to the bottom) and did great for another 3 miles when the boat began surging badly again and again pulled vacuum on the primer bulb, crushing it.

This time I burped the fuel filter (spin on cartridge) and had to continue to do so to get the boat back to the dock while on plane. Boat would still rev out so long as I kept burping the system. Checked the fuel filter after it was back on the trailer and still dirty as before.

Despite the dirty filter, I cannot for the life of me determine why this thing is pulling a vacuum on the bulb unless there is just too much crud at the fuel pickup for it to be able to flow more than 10 GPH. But that does not make sense to me because when I burped the system, the boat ran at 12.1 GPH the whole way back to the dock. Aren't these Sierra cartridges bypass filters anyhow?

Anyone have any thoughts on what might be the problem here and how I can fix this? :cen:

[jasoncooperpcola]

Where is the vent outlet on the tank? At the front or rear of the tank? It could be air locking. Also do you have an elbow at the tank? Some have back flow preventers and some just get clogged very easily. We pulled bumble bees out of the elbows on my Sportsman when it kept dieing on us.

If you think the tank is very dirty you may have to do what i did to my 250 Sportsman, cut a 6" circle through the tank and clean it manually. I had to pull 50 gallons of fuel out of the tank and then filled it with water before cutting. I pumped all the water out and flushed it with the garden hose and let it dry for a day. I then took a piece of 1/8" aluminum and used gasket paper to seal the hole back up. The only problem i have had since then is water getting into the tank due to a piss poor design. The overflow was getting flooded in rough water.

[phatdaddy]

sounds like the filter is doing its job and you have a lot of crud in the tank. try running on a portable tank and see if the problem goes away.

[spareparts]

replace all your fuel lines. Does it have the grey "quicksilver" fuel line? Cut a section off, slice it length wise, and open it up. You will probably see the inner lining of the fuel line turning brown and coming apart. Replace all the lines from the tank till you get above deck with A1 type line, its a little more, but it holds up better, replace all the above deck line with good quality B1( I use trident hose), replace the primer bulb with a good one made by Mercury, Bomb, or Yamaha. Make sure your water sep filter housing is flushed as well. Check the filters/strainers on the engine as well.

[spareparts]

Oh, and BTW, that thing doesn't have a fiberglass tank does it?

[cterrebonne]

your boat looks sharp man. in addition to what spare said, if you are replacing all the hose. If it were myself I would trash the anti-siphon fitting for a standard brass barb.

[randlemanboater]

I would trash the anti-siphon fitting for a standard brass barb.

Thats what was causing the same problem on mine.

[randlemanboater]

If it were myself I would trash the anti-siphon fitting for a standard brass barb.

I was having the same trouble once (bulb sucked flat), the anti-siphon was stuck.

[bksah2]

I Agree with patdaddy running on a portable tank and see what happens sounds like the reg. tank is filled with crud

[Shrek]

I've already replaced every fuel line in the boat. I also replaced the primer bulb. I pulled the fuel sender and pick-up and hoovered out the tank as best I could see and reach. There is no screen or anti-siphon valve on the tank.

I am taking it apart again on Wednesday and see whats happening then.

[Blue_Runner]

The anti-siphon - is it the fuel pickup y'all are referring to? I've had the flattened bulb sporadically almost as long as I have had the boat. At least 4 or 5 times. Each time I remove the fuel line from the H2O separator that runs to the tank and blow back into the tank to clear it.

I've always suspected trash and gunk in there but there's no sign of anything whatsoever in my fileter(s). So could it be as simple as the fitting getting stuck rather than trash in the lines? As a side note, I need to replace all of my hoses as well. I may get to it this winter, hopefully.

[spareparts]

the anti siphon valve is made into the hose barb fitting on the top of your tank, remove the hose barb and look thru it, you will see a check ball, spring and collar. I can't legally tell you what to do with it, But i've float tested them in the past, if it floats in water, its probably good(:zip:), I've taken a Phillips screw drive and punched the check ball, spring and collar out, just to see they were there :zip:

[cterrebonne]

you should probably get some one to open it up and clean it out.
I know these guys are out of houma but they do good work and a fair price.

H & P Sheet Metal Works
1138 Barrow St, Houma, LA 70360
52.0MI from New Orleans
(985) 868-2761

for someone closer try calling Metro Boating to see who they deal with for their aluminum fab work. They probably know someone in the area. If I remember correctly they would bring a lot of their repair work to Jefferson Fiberglass. I don't remember if they did aluminum work in addition to glass work or not.

Metro boating
3028 4th Street
Harvey, LA 70058-2828
(504) 341-4852

If you take the tank out your self I don't see anyone charging over 2 hours to do the job including pressure testing it.

[Blue_Runner]

Sounds like I may need to do a float test on mine. :zip:

[RidgeRunner]

Sounds like good info to me on the check valve float test.

Not to derail too badly. Cterrebonne, what is the name of the 30 to 40 foot aluminum center consoles that I have seen in your neck of the woods? They remind me of big Fiberglass boats like the Contenders, the workmanship is awesome.

[cterrebonne]

Sounds like good info to me on the check valve float test.

Not to derail too badly. Cterrebonne, what is the name of the 30 to 40 foot aluminum center consoles that I have seen in your neck of the woods? They remind me of big Fiberglass boats like the Contenders, the workmanship is awesome.

you must be talking about the Gravois Hulls.They are very nice and built solid. I know a local guy that sold a contender to buy the Gravois.

http://www.facebook.com/group.php?gid=230652745784&v=wall

then there is another smaller co with really good lines "Gaubert Boat Co." i believe.

[RidgeRunner]

That is the one. Gravois, I read their Info section they are only building patrol boats and such. Not much info on them. First glance at one and you would swear it was a fiberglass boat. Awesome, and thank you.

[Shrek]

The verdict is in.

My tank is 40 gallons. I emptied 17 gallons of fluid from the tank. 3 gallons of which was salt water. That would explain the surging. My tank vent is at the extreme stbd quarter of the boat at the transom, just below the rub rail and in front of the bilge pump outlet. I think that between the bilge and the spray from running on plane, I shoved a bunch of bayou water down the vent pipe and voila, problem. There was also a bunch of varnishy goodness in the bottom of the tank that I was able to hoover out. I blew the pickup tube out with compressed air; it was clean. I've already replaced all fuel lines with the good stuff prior to this problem and there is no pickup screen on the pickup tube, nor do I have an anti siphon valve.

My plan is to move the vent line on Friday and run it again on Saturday with a clean tank and see what happens.

[reelapeelin]

Shrek, I think you got your basic issue w/the location of the vent fitting...that's absolutely the last place to put an air intake...no wonder it had water in the tank...our V20s vents on some models are poorly located...I repositioned mine ABOVE the rub rail and never had another problem...

[cterrebonne]

glad to hear that that tank is ok and you just need to reroute the vent. let us know how it works.

[RidgeRunner]

Absolutely, the a-ha moment. Hope you do not have to look into cleaning the carbs. I love the looks of that Offshore. Best of luck to you.

[Shrek]

Thanks for the kind words. I'm going to run the snot out of it in the morning. Report to follow.

[RidgeRunner]

Rut Row.. No posts for a few days, how did it go?

[Shrek]

Rut Row.. No posts for a few days, how did it go?

It didn't. On the way down to the ramp, I had another blow-out. Spent the afternoon at the tire store instead. Sunday was a washout between a first birthday party and football. I have a sailing regatta this weekend, so the next available time is next weekend. Hopefully the warm weather holds so I can put a few more redfish on the boat while I'm at it.

Here are a couple of action pics from a couple of weeks ago.
http://i177.photobucket.com/albums/w207/rickelsky/Offshore22onplane.jpg
http://i177.photobucket.com/albums/w207/rickelsky/Offshore22atrest.jpg

[RidgeRunner]

Love it. The top and console (as someone already mentioned) really appeals to me. That is the exact look I was trying to achieve on mine. Looks sturdy too. Good luck on the reds, I got word from my mom that the bite has turned on.

[bradford]

Looks good Shrek.

[cterrebonne]

boat looks awesome!

[Shrek]

boat looks awesome!

Thanks Case, how you getting along with my old girl?

UPDATE: After draining the tank completely (again) and removing about 3 gallons of water from the bottom, I took the boat out for the first time last Saturday. It was not as bad as before, but still more of the same. The primer bulb never collapsed this time, but the more fuel I burned, the more performance degraded. By the end of our day, I'd burned 15 gallons and while the boat never stalled and was not burping and farting as it was before, it did not have enough power to get on plane. I changed the fuel filter again and there was more particulate material and some water in it, but not as bad as before. I'm at a loss. This week I am going to buy an electric fuel pump, a second fuel filter and separate water separator, intake from the pickup and return into the vent. See what we get.

[cterrebonne]

Thanks Case, how you getting along with my old girl?

UPDATE: After draining the tank completely (again) and removing about 3 gallons of water from the bottom, I took the boat out for the first time last Saturday. It was not as bad as before, but still more of the same. The primer bulb never collapsed this time, but the more fuel I burned, the more performance degraded. By the end of our day, I'd burned 15 gallons and while the boat never stalled and was not burping and farting as it was before, it did not have enough power to get on plane. I changed the fuel filter again and there was more particulate material and some water in it, but not as bad as before. I'm at a loss. This week I am going to buy an electric fuel pump, a second fuel filter and separate water separator, intake from the pickup and return into the vent. See what we get.

I have her in stored right now waiting to do some work to her. hope fully will be able to remove the cap this December.

Are you running 5/16 fuel line? Maybe trying some 3/8" so that the hose is bigger and can flow more junk into the water sep filter it might be clogging the the line itself. If you are already running 3/8 then my idea definitely wont work.

[Shrek]

Yep, everything is 3/8. I'm setting up a filtering rig this afternoon. I figure that I will jack up the front of the boat about 47 feet in the air and loop the fuel through an electric pump through a couple of filters/water separators and back into the tank through the vent. I'm going to run that all week and then we will see what happens.

[bradford]

Be careful Bro! Be sure there is no chance of any sparks etc. I'd be more inclined to siphon out the gas and inspect the tank or have it professionally cleaned.

[Shrek]

I think that I'll be fine. The battery leads are about 15 feet from the pump assembly so I don't think that spark will be an issue, plus everything is above decks except for the connections to the tank which are vapor tight anyhow. Hopefully the fuel pump that I've got has the testicular fortitude to suck a golf ball through a garden hose.

[smokeonthewater]

I've done the same thing before..... also tip the boat to the side so you have a low corner to draw from. remove the sender and put the suction hose in the low corner..... you prolly don't need to run it a week though... a couple hours should be plenty...

I would also definitely test with a portable tank... you may have carb or engine issues now and if so you want to figure that out sooner rather than later.... don't want to keep running the engine lean and burn it up

On that note you should prolly be carrying that tank with you on future tests so at the first sign of trouble you can swap and save your engine

[spareparts]

Shrek, I know this has been asked before, but are you sure that isn't a fiberglass tank(just making sure)

[Shrek]

I can only tell you that the portion that I can see is aluminum so I have assumed that the rest of the tank is too. The tank has been glassed into the stringers with chopper gun so I have no idea what the condition of the tank really is. I am absolutely bringing a separate tank this weekend and I guess that we will see what happens.

[smokeonthewater]

good luck..... I keep looking at your boat and as much as I don't WANT to like the color it is really growing on me..... I gotta resist lest I have a pumpkin colored boat too... LOL It really stands out.... no doubt at all which boat you see coming in the distance... I dig it..... dangit

[RidgeRunner]

I gotta agree with SOTW. Carbs must have crap in them with all the running around and all the water in the tank.

[Curapa]

Yeah, what yingxuy said.

[valiant_200]

Yeah, what yingxuy said.

Old yingxuy had to leave the site permanently, but I think what he was saying that he is a douchebag spammer and not fit for polite company.