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sk8salomon
05-26-2008, 07:27 PM
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
05-26-2008, 07:31 PM
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
05-26-2008, 07:36 PM
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!:mad:

88 PS190
05-26-2008, 07:45 PM
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
05-26-2008, 07:47 PM
Pretty sure one pump is high pressure, that other low. That's how mine is anyway, but different engines.

sk8salomon
05-26-2008, 07:48 PM
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
05-31-2008, 10:53 PM
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.:confused:

sk8salomon
06-03-2008, 11:01 AM
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/pbcs.dll/article?AID=/20080524/NEWS/805240354/1001

JerryS
06-03-2008, 11:01 AM
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
06-03-2008, 11:04 AM
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
06-03-2008, 11:21 AM
let's see what this looks like...

bigmac
06-03-2008, 11:24 AM
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
06-03-2008, 11:30 AM
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
06-19-2008, 05:04 PM
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
06-21-2008, 08:04 AM
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.

WTRSK1R
06-21-2008, 08:19 AM
I will start this post by saying I do not have a clue how this is actually wired, but it would be very strange to have the ECM even involved. I always thought the fuel pump is set up to run to get a certain pressue in the line and when it hits that pressure it shuts off. If there are only 2 wires (as shown in your graphic) then that would mean the ECM is either monitoring fuel flow, fuel pressure, or just the engine operation. I recognize that it DOES monitor the engine, but it would seem odd to me that it would know that fuel pressue is low when monitoring the various engine sensors. Course as I said, I do not have a clue what is all being tracked in the newer engines with Cat Convertors.

In any case, congrats that this is all warranty, and hopefully it does not happen again, or to anyone else.

bigmac
06-21-2008, 09:05 AM
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.

What boat are we talking about here? You have an 89 listed in your profile.

Putting in ZeroOff requires a whole new ECM? That sounds like a recipe for trouble.

JimN
06-21-2008, 09:06 AM
The fuel pump delivers the pressure it's designed for and the regulator determines what gets to the injectors. If what goes to the regulator is more than the motor needs, the return line sends it back to the tank. As long as the ECM gets RPM data, the pump is running. Sending fuel pressure info to the ECM is easy enough, with a pressure sensor.

The dual pump setup is factory installed?

sk8salomon
06-21-2008, 10:23 AM
What boat are we talking about here? You have an 89 listed in your profile.

Putting in ZeroOff requires a whole new ECM? That sounds like a recipe for trouble.

'07 MCPS197 TT

its not that the zero off requires a new ECM, the boat did not come factory with ZO, only PP. ZO had to install an upgraded ECM due to the aftermarket install. all new '08 boats with ZO will have this ECM that my '07 has.

The fuel pump delivers the pressure it's designed for and the regulator determines what gets to the injectors. If what goes to the regulator is more than the motor needs, the return line sends it back to the tank. As long as the ECM gets RPM data, the pump is running. Sending fuel pressure info to the ECM is easy enough, with a pressure sensor.

The dual pump setup is factory installed? yes, all the TT's come with the Mueller twin pump setup.

bigmac
06-21-2008, 10:34 AM
'07 MCPS197 TT

its not that the zero off requires a new ECM, the boat did not come factory with ZO, only PP. ZO had to install an upgraded ECM due to the aftermarket install. all new '08 boats with ZO will have this ECM that my '07 has.

yes, all the TT's come with the Mueller twin pump setup.
Interesting.

So, does the ECM control fuel pressure in this dual pump setup? Or is the problem with your fuel pressure regulator?

Does this dual pump setup signal a MasterCraft departure from the apparently problematic in-tank fuel pump setup they have been using on all their boats?

flipper
06-21-2008, 10:59 AM
Interesting.

So, does the ECM control fuel pressure in this dual pump setup? Or is the problem with your fuel pressure regulator?

Does this dual pump setup signal a MasterCraft departure from the apparently problematic in-tank fuel pump setup they have been using on all their boats?

It sounds like the ZO won't "talk" to the old ECM, so either the ECM was flashed to recognize the ZO, or a new one was put in. It doesn't sound like the ECM has any problem, just that he wanted ZO in his boat.

bigmac
06-21-2008, 11:40 AM
It sounds like the ZO won't "talk" to the old ECM, so either the ECM was flashed to recognize the ZO, or a new one was put in. It doesn't sound like the ECM has any problem, just that he wanted ZO in his boat.
He's blown a couple of hose in his fuel system. It's not due to ethanol, so presumably it's due to excessive pressure in his fuel system. This factory Mueller dual pump setup is a departure from MC's usual in-tank setup. I'm curious about that. Likewise, I'm curious whether the excessive pressure is from an erroneous signal from the ECM, or erroneous performance of the fuel pressure regulator.

sk8salomon
06-21-2008, 12:43 PM
Interesting.

So, does the ECM control fuel pressure in this dual pump setup? Or is the problem with your fuel pressure regulator?


I'd say more of a regulator problem than pump. I'm not sure how the regulator adjusts pressure signal to the pumps, like DC voltage or something?

This factory Mueller dual pump setup is a departure from MC's usual in-tank setup. I'm curious about that. Likewise, I'm curious whether the excessive pressure is from an erroneous signal from the ECM, or erroneous performance of the fuel pressure regulator.

This dual pump setup is still an "in-tank" assembly. There is a manifold "Y" piece that both pumps feed to, then outside the tank a single larger hose to the engine.

JimN
06-21-2008, 01:25 PM
The regulator uses vacuum from the engine to vary the flow.

Engine Nut
06-21-2008, 01:27 PM
He's blown a couple of hose in his fuel system. It's not due to ethanol, so presumably it's due to excessive pressure in his fuel system. This factory Mueller dual pump setup is a departure from MC's usual in-tank setup. I'm curious about that. Likewise, I'm curious whether the excessive pressure is from an erroneous signal from the ECM, or erroneous performance of the fuel pressure regulator.

All the ECM does is turn on the fuel pump. There is no device in the system to measure fuel pressure or regulate fuel pressure with the ECM. The fuel pressure is regulated at the pump with a mechanical regulator. I dont know much about the MC pumps but it looks to me like the regulator may be faulty allowing excessive pressure in the system that blew the fuel lines in the pump.

Engine Nut
06-21-2008, 01:30 PM
The regulator uses vacuum from the engine to vary the flow.

The pump in tank systems do not use a vacuum biased regulator.They use a mechanical regulator and the fuel pressure stays constant al all RPM.

sk8salomon
06-21-2008, 02:44 PM
The pump in tank systems do not use a vacuum biased regulator.They use a mechanical regulator and the fuel pressure stays constant al all RPM.

where is this mechanical regulator you speak of?

JimN
06-21-2008, 04:26 PM
I guess I was thinking the regulator was the same as TBI and LT-1.

It's on the pump, right?

Engine Nut
06-21-2008, 04:29 PM
I guess I was thinking the regulator was the same as TBI and LT-1.

It's on the pump, right?

Yes, it regulates at the pump. That is how we can get by with a single line from the pump to the engine. No more need for return lines from the engine to the tank.

sk8salomon
06-23-2008, 11:45 PM
That is how we can get by with a single line from the pump to the engine.

we? hhmmmmm....engine nut must be an inside guy!:worthy:

sk8salomon
06-29-2008, 08:53 PM
picked up the boat this saturday morning. everything was covered under warranty thankfully! just thought i'd post the final bill that MC will be taking care of. OUCH!!!:eek3:

bigmac
06-29-2008, 10:10 PM
Yikes! $400 in parts and $3000 for labor! They must have had to pull the engine?

sk8salomon
06-29-2008, 10:45 PM
Yikes! $400 in parts and $3000 for labor! They must have had to pull the engine?

no, just new fuel pump @ $500 + 30 hours labor with ECM diagnostics @ $95/hr.

JerryS
06-30-2008, 12:01 AM
30 HOURS??? That is 4 straight days practically working on nothing but that fuel pump issue from 8am-330pm....with no breaks for lunch etc.

Hate to see how many hours an oil/filter change would take.

sk8salomon
06-30-2008, 06:03 AM
30 HOURS??? That is 4 straight days practically working on nothing but that fuel pump issue from 8am-330pm....with no breaks for lunch etc.

Hate to see how many hours an oil/filter change would take.

yeah, that's kinda what i thought too but apparently the different ECM was unlike anything they had seen yet. so they had problems even hooking up a communication cable to it and figuring out the software changes to the diagnostics program. who knows

JimN
06-30-2008, 08:57 AM
"but apparently the different ECM was unlike anything they had seen yet. so they had problems even hooking up a communication cable to it and figuring out the software changes to the diagnostics program."

That's why MC has mandatory service training- so the dealers DON'T take 30 hours to diagnose ANY kind of problem and try to be reimbursed for all of it. They pay what they figure to be a normal amount of time and if the dealer actually did need 30 hours, they'll need to look at their idea that "sending our tech(s) to training costs us too much money". Granted, the fall session falls in winterization season for cold weather dealers and March isn't the best time to send people, either but it's better to send them then than not at all.

The dealer will not be paid for all of the time they supposedly spent in doagnosing this. It's their responsibility to have the correct connectors and be familiar with LAST YEAR'S models.