Jump to content

Welcome to TheMalibuCrew!

As a guest, you are welcome to poke around and view the majority of the content that we have to offer, but in order to post, search, contact members, and get full use out of the website you will need to Register for an Account. It's free and it's easy, so don't hesitate to join the TheMalibuCrew Family today!

Fuel issues again


Recommended Posts

I had half a tank of fuel and was running good. 01 vlx with injected monsoon. Stopped for a bit to swim and got back in and cranked it up. It ran at idle but quickly fizzelled out. Then each time i cranked, it would idle, sputter and die. I had to spend about 5 min nursing it and bumping the throttle pretty hard. Then it smoothed out and let me run just as normal. I thought it might be vapor lock. Then later it did it just off a 15 min run. I had to jog the throttle back and forth to keep it going just to get back to the dock. I was pretty close anyway. I dont think its vapor lock now. Acts like water in the fuel. Any ideas?

Link to comment

Sounds like vapor lock to me.  Mine does it pretty much all the time if I don't run the blower the whole time.  I also found that if I let it idle for a few minutes after towing before shutting down it seems to keep it from happening.  Next time poor some cold water on your fuel pump...lake water works fine ....see if it clears up your problem.  That's definitely the issue for me.

Gotta love ethanol....

  • Like 2
Link to comment

I agree with Duke...wouldn't rule out vapor lock quite yet.  Try to replicate it.  If it does it again, pour cold lake water (or ice water from the cooler) onto the fuel pump to cool it down.  If that solves it, you are a member of the club. 

Oh, and that allows membership into the Carter club too :biggrin:

Link to comment

Our '02 would do this all the time. We started running the blower all the time and it helped dramatically. When really hot 100*+ we would open the hatch and prop it up with a soda can to let the heat escape. Never had an issue after. 

Link to comment

I just read a thread where these are possible symptoms of vapor lock. Sucks too. I just replaced the fuel pump not two weeks ago with a unit from skidim and i use non ethonol gas. Never had a issue like this until now. Fuel pump did not feel hot nor very warm even and no whine. Fires right up each time and just seems to sputter and die unless i keep goosing the throttle. 

Can i put a water seperating fuel filter on it like you might use on a carb engine? 

 

Link to comment
1 hour ago, williemon said:

Can i put a water seperating fuel filter on it like you might use on a carb engine? 

Well, you'll see those who say you can't, but I did.  The advice against it is meant for the in-tank pumps, IIRC.  What most have done is add a 4-8psi Carter fuel pump upstream of the main fuel pump.  That small bit of head pressure is all that is needed to keep the vapor lock at bay.  My understanding is it is a small bubble at the main pump that causes the issue.  Other have had luck insulating the pump, running the blower or a combination of that. 

Link to comment

So if it were vapor lock, i would be able to keep the engine running as long as i kept goosing it in neutral or drive? This keeps rpms up to 1000 to 2000 until the bubbles pass? Im not sure i understand that. I assumed vapor lock was just that. No running in any kind of way till the vapor bubbles are gone and its liquid again. Its also never done this during the 2 years ive had it even on hotter days. Im thinking water in the fuel myself but then again, i e never delt with a vapor lock issue either. 

Link to comment

If you can replicate it again....try cool/cold water on the fuel pump.  If that takes care of it, there's your answer.  

Link to comment

Best way to be sure is locate schraeder valve on top of engine fuel system.  When boat wont start get a rag and depress valve.  If air comes out you have vapor lock.  Incidentally, this is what I had to do to purge the system to get it going but makes a gasy mess and when getting blown into the rocks by violent storm it is a bit stressful.

Link to comment

Well it does start. No problem there. Juts wont idle and run without my assistance goosing the throttle.  How hot does the pump have to be for vapor lock?

Edited by williemon
Link to comment

It won't even feel hot to the touch, just very warm.  You are describing exactly the symptoms of what I was having.  Also, what year and model do you have?

Link to comment
On 6/23/2016 at 9:33 PM, williemon said:

Fuel pump did not feel hot nor very warm even and no whine. 

Can i put a water seperating fuel filter on it

 

Does a whining fuel pump mean it's about to go bad? Mine whines sometimes, especially if the engine is cold. I run my blower at all times under 15mph or so if the engine is running, and about 3 or 4 minutes before starting the boat. 

My boat is the same as yours, and I have a water separator installed in the engine compartment. It was there when I bought the boat, so I always thought it was factory.

Don't some people also insulate the fuel lines to stop vapor lock?

Link to comment

I have a 2001 with monsoon. The old fuel pump did whine and this year it would not run good above 2800 rpm or so. I replaced fuel hose, filter and pump with a new skidim unit. Sucks now that a new pump is plagued with vapor issues if thats what it is. I had the exact symptoms on an older boat with a carb. It did get water in the tank so i installed the seperating filter.

 

i che ked the plugs today and they seem whiter than they should be but not blistered. Just very clean.

Link to comment
5 hours ago, Chatty21VLX said:

Does a whining fuel pump mean it's about to go bad? Mine whines sometimes, especially if the engine is cold. I run my blower at all times under 15mph or so if the engine is running, and about 3 or 4 minutes before starting the boat. 

My boat is the same as yours, and I have a water separator installed in the engine compartment. It was there when I bought the boat, so I always thought it was factory.

Don't some people also insulate the fuel lines to stop vapor lock?

Typically when the fuel pump whines it is due to a lack of flow to the pump. Replace the fuel filter, replace or clean the fuel/water separator. 

Link to comment

Another club member here, though not much in the past few years.  Propping the dog house up when parked helps a lot, basically anything to let some of the heat out.  Idling for a minute or two does the same thing by allowing the motor to cool.  Mine would idle and run but barely and smelled horrible until it was cleared.  You can also try switching gas stations to see if that helps, some places get a little bit "heavy" with the ethanol. 

  • Like 1
Link to comment

Vapor lock is when the fuel turns to vapor before it enters the fuel pump.  This is caused by heat/altitude/low vapor pressure fuel (winter gas). When this happens, the fuel pump isn't able to pump vapor very well so it isn't able to purge the vapor from the system.  If the fuel pump is at or in the fuel tank, vapor lock is prevented.

Auto manufactures have been doing this for years, the first car I was familiar with the fuel pump in the tank was the Chevy Vega in the '70's.  Marine engine suppliers have been slow making this change.

  • Like 2
Link to comment

Found this odd. I pulled the fuel pickup tube from the tank and all looked good. I pulled the fuel sending unit from the tank and there were a lot of metal particles on the magnetic float. There were none on there a month ago when i pulled it to test its function. Only thing in the path is a new fuel pump installed afterwards because the old one did not perform well above 2800 ish rpm. Everything was cleaned prior to installing the new pump.  Could this new pump be spitting out metal into the fuel return line to the tank or could i have gotten this from the gas stations i get my fuel from?

 

im also goint to get and install a water seperating filter just for my poece of mind. I will also try and insulate this fuel pump to prevent any heat buildup. 

Edited by williemon
Link to comment

Well its not vapor lock. I drained the tank, used a magnet to pull a little metal out of the tank, put it together and refueled with non ethanol. I turned the key and heard the fuel pump prime, then it got quiet, then i cranked it. It fired right up and idled for a moment and then started stumbling. I quickly put my hand on the fuel pump and it felt cool. Then as the engine stumbeled a bit more, the fuel pump started whineing. Then, The engine died and the fuel pump kept running but squeled louder and got warm. It did this twice while on the hose. I was worried i may damage the pump so i just put it away since it was getting late. I wonder now if the fuel filter is plugged. I will need to get another one tomorrow and take that section apart again. Yall have any ideas? 

Link to comment

How many times did you "key up" or prime before your first run after cleaning the tank?  There may have been a good air bubble in those lines...

Link to comment

Hmm.. I only keyed up once. I guess i should have hit it a few times to be sure i had a good full flow in the line. Maybe i will try that tomorrow. 

Link to comment

Yeah, might sound like abuse, but I would serious key up at least a dozen times as it will pressurize the lines, and then you'll hear it slowly purge into the return line if you don't crank.  Or you can also crack open the line downstream of the pump on the fuel rail and catch the fuel there to ensure at that at least the pump has a solid prime.  Just be careful with all that fuel!!

Link to comment

I got a clear plastic filter (for testing only) and put it in place of the metal filter. I primed the system about 10 times and could see the fuel fill up the filter and move within it. The. I started the engine and it idled good. I then Noticed some fuel residue on the top of the fuel rail where the pressure reliefe selenoid is. I discovered a small leak there. I shut the engine off and proceeded to remove the pressure relief. Once it was off i discovered metal particals in the fuel rail. I fished them out with a magnet. I cleaned the hole and the selenoid, removed the rubber o ring and cleaned. Used vasoline to lube the o ring and re installed everything. Unfortunately, it still leaks there on e the fuel rail get pressured. Anyone think i can get an o ring to fit from the auto store?

Link to comment

Wow, a lot going on here, but my gut instinct (which could be very wrong) is that the metal particles are collateral debris and that you may have fixed your problem and now all you need is a good o-ring to stop the leaking...fingers crossed that is the case.  I would take the o-ring to the local parts store and see what you can find.  Fingers crossed!

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...