Fuel Issue - 2000 Formula 31PC 454 MPI

[390Express]

Boat has a bad fuel issue. Fuel was drained completely, re-filled with fresh fuel, new fuel pump, couple new fuel lines, and still won’t take gas from either of the two tanks.

Seems to run well off of a Jack tank. Could the tanks themselves be bad, or is it likely limited to the fuel lines? I believe the fuel tanks are aluminum, they’re definitely metal and not plastic/poly, etc.

There is a bit of a gasoline odor in the aft cabin, which sits right in front of the stbd tank.

Both engines seem to have the same issue, despite running off of separate tanks. Wondering if E10 gasoline (I never put E10 in the boat, but no telling what a prior owner did) has had a separation issue, and if so, if it only affected the lines, or if it also affected the injectors and tanks.

Boat idles fine, but won’t run under a load, and sometimes stalls at idle. Any ideas?

 

[bondo]

Boat has a bad fuel issue. Fuel was drained completely, re-filled with fresh fuel, new fuel pump, couple new fuel lines, and still won’t take gas from either of the two tanks.

Seems to run well off of a Jack tank. Could the tanks themselves be bad, or is it likely limited to the fuel lines? I believe the fuel tanks are aluminum, they’re definitely metal and not plastic/poly, etc.

There is a bit of a gasoline odor in the aft cabin, which sits right in front of the stbd tank.

Both engines seem to have the same issue, despite running off of separate tanks. Wondering if E10 gasoline (I never put E10 in the boat, but no telling what a prior owner did) has had a separation issue, and if so, if it only affected the lines, or if it also affected the injectors and tanks.

Boat idles fine, but won’t run under a load, and sometimes stalls at idle. Any ideas?

Ayuh,...... The outlet fitting is the anti-siphon valve, which could be plugged,.....

 

[390Express]

Ayuh,...... The outlet fitting is the anti-siphon valve, which could be plugged,.....

On both tanks, simultaneously, getting plugged at the same time?

Boat owner reports that the port tank fuel pump went bad due to contaminated fuel, and a plugged fuel pump inlet… claimed that it has seaweed and even a couple small zebra muscles stuck in the inlet.

Could that be a sign that the fuel cooler went bad?

 

[makomark]

if both tanks got a bad batch of fuel from the same pump, then (nearly) simultaneous failures are very possible...especially if the boat isn't used regularly.

that kinda of material in the fuel system suggests something has failed for sure...and the cooler is a likely subject.

 

[AllDodge]

What is fuel pressure? It should be 42 psi at idle thru WOT

If any of the crud in the tanks made it past the filter then the injectors need to be cleaned and flow tested.

 

[390Express]

if both tanks got a bad batch of fuel from the same pump, then (nearly) simultaneous failures are very possible...especially if the boat isn't used regularly.

that kinda of material in the fuel system suggests something has failed for sure...and the cooler is a likely subject.

Thanks, I do not suspect bad gas, but stranger things have happened. The current fuel filters look good. Fuel pressure is good, but both engines run like garbage. It will occasionally stall at idle, and won't run under a load at all (it'll run up to around 1500 rpm, and fall on its face). Runs good off of a jack tank with the entire fuel system bypassed, but that doesn't help much. There is no easy way to incorporate the jack tank in a systematic manner to rule out trouble spots.

Injectors seem to be ok, but I can't run under a load with the jack tank setup. I'm just trying to figure out if my entire issue is limited to the fuel cooler/fuel pumps, or if the tanks and lines are bad. The boat is a year 2000, I wasn't sure if the lines are rated for E10 or not, and also unsure if ethanol separation would or could have a detrimental effect on an aluminum gas tank. I know it was hell on the old galvanized tanks.

I have never put E10 in the boat, but have no idea what previous owners have done.

 

[AllDodge]

@000 has no issue with E10
E10 will last maybe 1 year before it starts to phase separate if something like Stabil is not added before it starts. Even with Stabil it still doesn't last a lot longer

 

[390Express]

@000 has no issue with E10
E10 will last maybe 1 year before it starts to phase separate if something like Stabil is not added before it starts. Even with Stabil it still doesn't last a lot longer

Yea, I'm aware of all of that. I just wasn't sure if the fuel system in a 2000 (gas tank and lines) could hold up to phase separated fuel. Any E10 fuel that gets more than approximately 2% water in it, will instantly phase separate, with Stabil or not. I didn't know if I'm looking at all new tanks, lines, and fuel pumps... I can handle new fuel coolers, pumps and lines, I have no stomach for replacing gas tanks. I'd have to pull the engines, (which results in also pulling the drives), pull the genny, etc. That's a huge job, that I have no interest in undertaking.

From what I've read, aluminum tanks and alcohol are no good. And once phase separation occurs, you'll have pure alcohol at the bottom of your tank:

The corrosion behavior of aluminum alloys in the presence of alcohol: (PDF)​

https://www.nmma.org/lib/docs/nmma/gr/environmental/E20_Position_Paper.doc#:~:text=fiberglass%20fuel%20tanks.-,Aluminum%20Fuel%20Tanks,a%20good%20measure%20of%20protection.

 

[o2batsea]

Let's be clear. Phase separation occurs in the presence of water. No excess water, no phase separation. If the tanks are heat cycled enough to produce condensation, that's a source of water. If there's water contamination in the supply, that's a source of water.
Just sitting in a tank for extended periods will not cause phase separation. If it did there'd be a lot more trouble with the gasoline (e10-85) supply in the world.
Phase separation occurs when the amount of dissolved water exceeds the oxygenated fuel's ability to suspend it. It takes a LOT of excess water.
It's more likely that water contamination has happened, leading to accumulation in the bottom of the tank, than actual phase separation.
Not saying this is the OP's issue, just that there's a lot of misunderstanding surrounding ethanol fuels.

 

[jimn]

@000 has no issue with E10
E10 will last maybe 1 year before it starts to phase separate if something like Stabil is not added before it starts. Even with Stabil it still doesn't last a lot longer

In a sealed tank, maybe but in a vented tank, no. Only stabilizer made for fuel with Ethanol will work- red StaBil isn't.

Phase separation is the extreme case of moisture absorption, but problems can arise before it reaches that level.

 

[jimn]

Thanks, I do not suspect bad gas, but stranger things have happened. The current fuel filters look good. Fuel pressure is good, but both engines run like garbage. It will occasionally stall at idle, and won't run under a load at all (it'll run up to around 1500 rpm, and fall on its face). Runs good off of a jack tank with the entire fuel system bypassed, but that doesn't help much. There is no easy way to incorporate the jack tank in a systematic manner to rule out trouble spots.

Injectors seem to be ok, but I can't run under a load with the jack tank setup. I'm just trying to figure out if my entire issue is limited to the fuel cooler/fuel pumps, or if the tanks and lines are bad. The boat is a year 2000, I wasn't sure if the lines are rated for E10 or not, and also unsure if ethanol separation would or could have a detrimental effect on an aluminum gas tank. I know it was hell on the old galvanized tanks.

I have never put E10 in the boat, but have no idea what previous owners have done.

Any boat built after 1998 has fuel lines that can handle some kind of Alcohol. First, it was MTBE and they ended that not long after finding it in ground water near lakes. Then, the idiots in charge rolled out Ethanol, against the recommendations of every engine manufacturer but, hey, THEY must know- they're from the government.

I know someone who has a 1989 Carver and near the fuel filler is a plastic tag with "Using fuel with alcohol is dangerous". I assume this is in reference to peoples' recommendation to add alcohol to fuel that has water in it, called 'dry gas'. Some people believed that "if a little is good, a lot must be great", so they add more than necessary.

I'd like to see your thought process on this. Searching for the cause of a 'no fuel at the engines' problem needs to start at the tank's fuel pickup tube, IN the tank. At some point, the fuel line needs to be disconnected at both ends and low pressure air provided, to make sure the line is clear. If you can't measure fuel pressure at the Shrader valve, you have a blockage. If the pickup tube has a screen and it's clogged, don't assume that everything was stopped by it.

I agree that the anti-siphon valve should be checked, but you may also have a fuel shutoff valve- make sure the lever is aligned with the fuel line.

 

[o2batsea]

@000 has no issue with E10
E10 will last maybe 1 year before it starts to phase separate if something like Stabil is not added before it starts. Even with Stabil it still doesn't last a lot longer

This is not the case at all and shows a common misunderstanding of oxygenated fuels.

 

[390Express]

This is not the case at all and shows a common misunderstanding of oxygenated fuels.

I agree.

Not saying this is the OP's issue, just that there's a lot of misunderstanding surrounding ethanol fuels.

I agree, but chose to ignore a discussion with AllDodge as to whether he was right or wrong regarding time, vs water causing the issue of phase separation, that juice wasn't worth the squeeze.

Any boat built after 1998 has fuel lines that can handle some kind of Alcohol. First, it was MTBE and they ended that not long after finding it in ground water near lakes. Then, the idiots in charge rolled out Ethanol, against the recommendations of every engine manufacturer but, hey, THEY must know- they're from the government.

I know someone who has a 1989 Carver and near the fuel filler is a plastic tag with "Using fuel with alcohol is dangerous". I assume this is in reference to peoples' recommendation to add alcohol to fuel that has water in it, called 'dry gas'. Some people believed that "if a little is good, a lot must be great", so they add more than necessary.

I'd like to see your thought process on this. Searching for the cause of a 'no fuel at the engines' problem needs to start at the tank's fuel pickup tube, IN the tank. At some point, the fuel line needs to be disconnected at both ends and low pressure air provided, to make sure the line is clear. If you can't measure fuel pressure at the Shrader valve, you have a blockage. If the pickup tube has a screen and it's clogged, don't assume that everything was stopped by it.

I agree that the anti-siphon valve should be checked, but you may also have a fuel shutoff valve- make sure the lever is aligned with the fuel line.

Thanks for the information. I knew there was a period of time (after 1996) that fuel lines, et. al were better engineered to handle E10, but wasn't sure when that was. I didn't know if it started in 1998 or after 2000. I knew that alcohol is dangerous to use in plastic or poly tanks, (also know that it's complete **** for galvanized tanks), but not sure what the effects are with alcohol sitting in aluminum tanks.

To clarify, the boat gets gas to the engine, just not enough. I can see where my OP caused confusion, when I said that the engines "won't take fuel." I clarified that a bit later, at least implicitly, when I said that they'll idle. They'll run most of the time, idle fine most of the time (they'll occasionally cause fits), but they generally won't go above 1500 rpm under a load, unless they're being supplied from a jack tank (small, separate tank). I really just need to know, with some sort of degree of certainty, if I'm going to have to replace the tanks or not.

I appreciate the discussion regarding anti-siphon valves and shut off valves, but those are not at issue here.

 

[jimn]

Thanks for the information. I knew there was a period of time (after 1996) that fuel lines, et. al were better engineered to handle E10, but wasn't sure when that was. I didn't know if it started in 1998 or after 2000. I knew that alcohol is dangerous to use in plastic or poly tanks, (also know that it's complete **** for galvanized tanks), but not sure what the effects are with alcohol sitting in aluminum tanks.

To clarify, the boat gets gas to the engine, just not enough. I can see where my OP caused confusion, when I said that the engines "won't take fuel." I clarified that a bit later, at least implicitly, when I said that they'll idle. They'll run most of the time, idle fine most of the time (they'll occasionally cause fits), but they generally won't go above 1500 rpm under a load, unless they're being supplied from a jack tank (small, separate tank). I really just need to know, with some sort of degree of certainty, if I'm going to have to replace the tanks or not.

I appreciate the discussion regarding anti-siphon valves and shut off valves, but those are not at issue here.

Ethanol isn't dangerous with plastic tanks, AFAIK and have never seen a galvanized tank in a boat- that doesn't seem like a good idea because paints with VOC are a no go on galvanized metal.

If "not enough" fuel reaches the injectors, you're looking at a blocked line, bad pump, bad regulator- the indicator of this would be seeing constant pressure at all speeds.

TEST, don't just replace. If you use a temporary tank and it runs, it wouldn't be the tank causing the problem, it would be the pickup tube/anti-siphon/shut off- all the tank does is hold fuel.

 

[Fun Times]

To clarify, the boat gets gas to the engine, just not enough.

Being a bigger Formula boat model, how does the generator seem to run underload? < Though not a strong indicator, it sometimes may help give an indication of an underlining tank hardware to equipment type issue on paper.

Are the fuel lines from the tank to engine (and generator) running direct or is there a fuel selector valve of any kind incorporated into the boat flow system for different operational purposes?…< Any inline fuel filter/s on the fuel hoses or Y type fittings that split the Gen and engines say at the tank or elsewhere?

From an Formula owners manual,​

FUEL SYSTEM​

Check your fuel system before each
operation. Have your fuel system
thoroughly checked at least once a year by a certified Formula service technician.
Gasoline is highly flammable. Use extreme
caution at all times.
The line between the fuel tank and the fuel inlet of the engine is made of a synthetic material. Alcohol
can deteriorate it, especially during periods of storage. Have your Formula dealer inspect this
fuel line at least annually and replace, if necessary.
The generator uses fuel from either the port or starboard fuel tank, depending on the model. The
fuel tank that shares its fuel between an engine and the generator holds additional fuel. Refer to Specifications, in Section 3, for the fuel tanks capacities.
Refer to your propulsion unit operator's manual for additional fuel system information.

Section 5-System Operation And Equipment; Powertrain; Fuel System; Helm System - Formula Cruiser Owner's Manual [Page 53]

Formula Cruiser Manual Online: section 5-system operation and equipment, Powertrain, Fuel System, Helm System. The Helm (Steering) System Is Not Self-Centering. Be Sure To Keep A Sure Grip On The Steering Wheel At All Times. Your Formula Boat Has One Of The Following Steering Systems:...

www.manualslib.com

Just some additional thoughts to consider looking at next time you’re in the boat diagnosing things out.

 

[390Express]

Ethanol isn't dangerous with plastic tanks, AFAIK and have never seen a galvanized tank in a boat- that doesn't seem like a good idea because paints with VOC are a no go on galvanized metal.

If "not enough" fuel reaches the injectors, you're looking at a blocked line, bad pump, bad regulator- the indicator of this would be seeing constant pressure at all speeds.

TEST, don't just replace. If you use a temporary tank and it runs, it wouldn't be the tank causing the problem, it would be the pickup tube/anti-siphon/shut off- all the tank does is hold fuel.

Trying to do some diagnosis before I break the engine engine down. The boat owner reports that there was "sea weed, and even a zebra muscle" in the fuel system. The only potential cause of the same seems to be from a failure of the fuel cooler. I don't see any other way for water/seaweed/a small zebra muscle to make its way into the fuel system.

Galvanized tank use was stopped around 1982.

Limited research suggests that alcohol can cause plastic/poly tanks to get brittle and crack.

A bit more research indicates that while E10 is not supposed to be harmful to aluminum gas tanks, phase separation, caused by the intrusion of water into the tank would cause near pure alcohol in the bottom of the tank, and that would cause rapid corrosion:

"In the case of aluminum tanks, aluminum is a highly conductive metal that relies on an oxide layer for its corrosion protection properties. Low levels of ethanol, such as E10 (10%), are usually not a problem in aluminum tanks because the oxide layer provides a good measure of protection."

The problem is, once corrosion starts, when does it stop? Does it continue to corrode, even after the E10, alcohol, water is removed, or does it continue, even after the tank is full of rec fuel? If the tank is going to continue to corrode, and the injectors are bad, are new injectors going to keep going bad, with further corrosion of the tank?

 

[jimn]

Trying to do some diagnosis before I break the engine engine down. The boat owner reports that there was "sea weed, and even a zebra muscle" in the fuel system. The only potential cause of the same seems to be from a failure of the fuel cooler. I don't see any other way for water/seaweed/a small zebra muscle to make its way into the fuel system.

Galvanized tank use was stopped around 1982.

Limited research suggests that alcohol can cause plastic/poly tanks to get brittle and crack.

A bit more research indicates that while E10 is not supposed to be harmful to aluminum gas tanks, phase separation, caused by the intrusion of water into the tank would cause near pure alcohol in the bottom of the tank, and that would cause rapid corrosion:

"In the case of aluminum tanks, aluminum is a highly conductive metal that relies on an oxide layer for its corrosion protection properties. Low levels of ethanol, such as E10 (10%), are usually not a problem in aluminum tanks because the oxide layer provides a good measure of protection."

The problem is, once corrosion starts, when does it stop? Does it continue to corrode, even after the E10, alcohol, water is removed, or does it continue, even after the tank is full of rec fuel? If the tank is going to continue to corrode, and the injectors are bad, are new injectors going to keep going bad, with further corrosion of the tank?

"In the fuel system isn't the same as "in the tank"- where is the fuel cooler? At the engine, right? Why are you looking at the tank.

Alcohol mixes well with gasoline and also water- how could pure alcohol be at the bottom of the tank without mixing with the water? Phase separation isn't defined as 'when the alcohol and gasoline separate", it happens when the alcohol & water reach a point of over-saturation and can no longer remain mixed with the gasoline. The bottom layer is gas & alcohol, heavier than gasoline (water is more dense) and it's usually cloudy.

WRT aluminum tanks and ethanol- the goof who owned the boat I bought is one of those who should just rely on others when he wants to go boating. Someone removed/possibly replaced the fuel tank sender and used random screws, with the sender rotated, so its holes didn't match the ones in the tank. One of the first things I did once I found that the engine needed major work was to search for the source of the gasoline odor and it was clear when I removed the floor panel. I removed the sender, siphoned the old/bad gas out and when it was empty, looked inside- the Aluminum looked fine and this is a boat made in 1984. I saw no oxide layer.

Aluminum is reactive- that's a chemical thing, 'conductive' is electrical- not sure if you believe this is associated with problems in the fuel but metal tanks are grounded to eliminate/ground static electricity that's caused by leaks/rich fuel mix or leaks. When people are working on the boat in dry air, the static is discharged when they touch metal in the presence of combustible fumes, like when the sender is out and the hole is open. Static is also discharged when metal touches metal that's grounded, so be careful.

What is 'rec fuel'? If your gas is polluted, you need to remove it, clean the tank, clear the fuel system up to the injectors, clean the injectors separately, then make sure the fuel lines are unaffected by the Ethanol or MTBE, if that was used.

Once you have a clean fuel system, the corrosion should stop, but only if water is removed on a constant basis. The fact that a fuel/water separator is just before the engine should tell you that water doesn't affect modern tanks,

Show your sources of the quoted information.

ETHANOL FUEL IN BOATS: Myths, Facts and Solutions | Thunder Marine

ETHANOL FUEL IN BOATS: Myths, Facts and Solutions - Boating News and Tips at Thunder Marine in St Petersburg FL

www.thundermarine.com

 

[390Express]

"In the fuel system isn't the same as "in the tank"- where is the fuel cooler? At the engine, right? Why are you looking at the tank.

Alcohol mixes well with gasoline and also water- how could pure alcohol be at the bottom of the tank without mixing with the water? Phase separation isn't defined as 'when the alcohol and gasoline separate", it happens when the alcohol & water reach a point of over-saturation and can no longer remain mixed with the gasoline. The bottom layer is gas & alcohol, heavier than gasoline (water is more dense) and it's usually cloudy.

WRT aluminum tanks and ethanol- the goof who owned the boat I bought is one of those who should just rely on others when he wants to go boating. Someone removed/possibly replaced the fuel tank sender and used random screws, with the sender rotated, so its holes didn't match the ones in the tank. One of the first things I did once I found that the engine needed major work was to search for the source of the gasoline odor and it was clear when I removed the floor panel. I removed the sender, siphoned the old/bad gas out and when it was empty, looked inside- the Aluminum looked fine and this is a boat made in 1984. I saw no oxide layer.

Aluminum is reactive- that's a chemical thing, 'conductive' is electrical- not sure if you believe this is associated with problems in the fuel but metal tanks are grounded to eliminate/ground static electricity that's caused by leaks/rich fuel mix or leaks. When people are working on the boat in dry air, the static is discharged when they touch metal in the presence of combustible fumes, like when the sender is out and the hole is open. Static is also discharged when metal touches metal that's grounded, so be careful.

What is 'rec fuel'? If your gas is polluted, you need to remove it, clean the tank, clear the fuel system up to the injectors, clean the injectors separately, then make sure the fuel lines are unaffected by the Ethanol or MTBE, if that was used.

Once you have a clean fuel system, the corrosion should stop, but only if water is removed on a constant basis. The fact that a fuel/water separator is just before the engine should tell you that water doesn't affect modern tanks,

Show your sources of the quoted information.

ETHANOL FUEL IN BOATS: Myths, Facts and Solutions | Thunder Marine

ETHANOL FUEL IN BOATS: Myths, Facts and Solutions - Boating News and Tips at Thunder Marine in St Petersburg FL

www.thundermarine.com

FFS, the entire fuel system is tied together, with a return line to the gas tank. If there was water, seaweed, zebra muscles at the fuel pump, there was definitely water in the gas tank. The later may have been caught by the fuel filter/water separator, but the water separator would not have stopped a significant inflow of water from the fuel cooler, nor is it designed to. The fuel pump pumps gas at 140 gph back to the tank, with the water in it. If the fuel cooler is bad, you're going to get water in your gas tank, and a lot of it.

If you want the source of the quote, google it, it takes 10 seconds.

 

[jimn]

FFS, the entire fuel system is tied together, with a return line to the gas tank. If there was water, seaweed, zebra muscles at the fuel pump, there was definitely water in the gas tank. The later may have been caught by the fuel filter/water separator, but the water separator would not have stopped a significant inflow of water from the fuel cooler, nor is it designed to. The fuel pump pumps gas at 140 gph back to the tank, with the water in it. If the fuel cooler is bad, you're going to get water in your gas tank, and a lot of it.

If you want the source of the quote, google it, it takes 10 seconds.

And where, exactly, was the entire fuel system's layout shown before this post? Are all fuel systems the same? No, they aren't.

How would a Zebra Mussel be identifiable in this system, small shards of the shell? Surely not a whole mussel.

 

[390Express]

And where, exactly, was the entire fuel system's layout shown before this post? Are all fuel systems the same? No, they aren't.

How would a Zebra Mussel be identifiable in this system, small shards of the shell? Surely not a whole mussel.

The fuel system is common, for all 454 MPI models. Perhaps the issue here is that you're commenting on a system, that you know nothing about?

Zebra mussels are easily identifiable, whole zebra mussels can be far smaller than fingernail, generally around 1/4, or less. It was not shards of shells in the system, it was small, whole mussels. Again, the only apparent way for them to get into the fuel system would be through the fuel cooler.

You apparently have nothing to offer this conversation, and instead want to argue semantics and about issues unrelated to the problem with the fuel system.