Dual fuel pumps

[sk8salomon]

just finished my 3rd ski pass yesterday when my buddy circled around me for a chat. all of a sudden, the engine just died. my buddy tried restarting but nothing. so was pulled back to the dock to tinker. i removed the cap on the fuel rail, turned the key on and could hear the fuel pump prime up. then i took a small screwdriver and pushed in on the schrader valve on the fuel rail, no fuel at all! being a holiday weekend i figured i was pretty fawked so i got out my tools and removed the fuel pump assy. looks like my boat has dual fuel pumps which is a good thing i guess. check out this hose.

[sk8salomon]

this friggen hose reminds me of the bendy/twisty straws you get at six-flags with a lemon-icy. come on guys, what the hell??? so today i went to the parts store and picked up some 3/8" fuel hose & clamps. reinstalled and back in biz. i let idle for about 10 minutes and reved the engine a bit. all a sudden, the engine died again! removed the pump assy AGAIN only to find the 2nd hose now blown. this has to be the dumbest hose i've ever seen in my life. what is going on here???

[sk8salomon]

so after some thought i figured this for a dual pump design.... if one pump would go bad, the other pump would probably have enough pressure to at least idle the boat somewhere safe. in my case, since the sending line was severed, the 1st pump was basically dumping fuel back in the tank. the 2nd pump was pumping up the tube into the manifold but then falling back down the 1st pumps broken tube and back into the tank, hence no fuel to the engine. maybe some kind of check valve would let the fuel at least get to the engine instead of returning to tank. i'd say since i replaced the 1st hose with a better quality fuel line, it overpowered the 2nd good hose and eventually ruptured it? who knows but thought i would post this. on a positive note, MC did do a good job designing an easy remove & reinstall pump assy. pat on the back guys but give me a break!

[88 PS190]

It could be that the ethanol in fuel ate that hose, notice that most things say to use ethanol free fuel, but that's a myth in this area, don't think I've seen fuel w/o 10% ethanol since 2003

[flipper]

Pretty sure one pump is high pressure, that other low. That's how mine is anyway, but different engines.

[sk8salomon]

It could be that the ethanol in fuel ate that hose, notice that most things say to use ethanol free fuel, but that's a myth in this area, don't think I've seen fuel w/o 10% ethanol since 2003

wow, that doesn't sound good for others! i couldn't believe how it looked as if the gas just melted thru the hose.

[sk8salomon]

well, the new rubber fuel line hoses have been in exactly one week. put the boat in today and it took a few seconds to crank up which made me nervous after a perfect mem.day monday. after about 1 minute of rough idling, the engine died again. immediately, i pulled the fuel pump assy noticing one of my new hoses dangling with a hose clamp. i noticed the rubber fuel hose has swollen some, maybe 1/4" overall and i must have not tightened the clamps enough. the hose just shot right off the port on the top side of the fuel pump. even tho the rubber hose was fuel rated, i'm wondering if the entire hose is rated for fuel, not just the inside. being that the entire hose is submerged in gas inside the tank, i'm wondering if i made a mistake here? i put the hose back on and tightened all the clamps up. what i now notice is that because the fuel line is much softer now, the hose clamps really dig into the rubber, almost cutting it. put everything back together, started right up. i let idle for about 10 minutes, giving throttle up and down to 3000 rpm or so, and notice a hesitation and backfiring sound. maybe one of those hose clamps punctured the line and can't get enough pressure? i'm tired of fooling with it, took it in to the dealership this afternoon.

[sk8salomon]

guys, the more and more i read up on ethanol and boats the more concerned i get. is this not a serious issue? especially lately with the added % of ethanol in gasoline. http://www.statesmanjournal.com/apps...805240354/1001

[JerryS]

Did you snap any pics of the pump assembly as you opened the tank up? Just to put into perspective where these lines are.

I have the 07 TT boat as well. Our boats have the 2008 Millenium pumps in them, which are different from the 07' production pumps. We have the equivalent to 2008 and above's pump assemblies. Supposed to be better.....

[sk8salomon]

sorry, no pics but i'll photochop one up for ya so you get the idea. is the millenium a "mueller" brand? if so, i have the same setup then.

[sk8salomon]

let's see what this looks like...

[bigmac]

Indmar and MasterCraft both state that fuel with 10% ethanol or less is acceptable for use in these boats....current models, anyway. Dunno about boat from the 80's, but I do know that ethanol is here to stay. Gettin' darn tough to find non-oxygenated fuel.

Just sayin'...

[sk8salomon]

Indmar and MasterCraft both state that fuel with 10% ethanol or less is acceptable for use in these boats....current models, anyway. Dunno about boat from the 80's, but I do know that ethanol is here to stay. Gettin' darn tough to find non-oxygenated fuel.

Just sayin'...

yeah, just reading some more articles that say it really doesn't affect you unless you have a fiberglass tank. i've read some horror stories about large yachts catching on fire because the fuel ate thru the tank and eventually filled the hull with gas!

[sk8salomon]

just thought i'd give an update on my boat.

MC says the had to replace the entire fuel pump assy but will only warranty the part if i have the broken hoses. I cannot for the life of me remember where I put them or if I tossed in the trash. I'm hoping pictures will be enough? Anyways, after some deep thoughts by jack handy, I'm wondering what would cause both lines to explode like this? What regulates fuel pressure? If this device was malfunctioning, it is possible that the fuel pumps are giving too much pressure. The replaced rubber hoses I installed blew off the pump fitting as well so I'm now wondering if a new pump assy is a waste of time? Any ideas?

[sk8salomon]

well, i called the dealership yesterday to check on the boat. apparently, due to the zero off installation, the boat has a 2009 ECM and the dealer has no idea how to hook up the diagnostics to this one. i guess all new zero off boats will have this ECM. according to the dealer, they were able to hook up to the computer and the check engine code i was getting was "fuel pressure" related. this only confirms my above post that something in the ECM told the fuel pumps to increase fuel pressure which eventually blew both hoses. since this is an ECM issue, the MC dealer said it all is covered under warranty and i don't need the blown hoses for proof. they only problem now is that nobody is sure why the ECM did this and what needs to be done to either clear the code or make an adjustment in the ECM so it doesn't happen again.