Engine won`t run, when hot??????

[Mommy and The Boys]

I have a 2005 Response LXI (340 Monsoon EFI). Just bought it this year. Low hours, Mint!! It runs great all the time? Last week we had heat index`s in the 100`s. We were on the Lake all week, so not so bad.. When we ran the boat for a couple hours, then had lunch or hit the sand bar for R&R. Then she would only turn over and put-out. (engine temp 160-170). Seemed like a Vapor lock?? Opened engine compartment, ran blower for 20-30 mins. Then she would run like nothing ever happened?? This happened 4-5 times last week?? Mechanic`s I talked to said an EFI shouldn`t vapor lock???? Has anyone heard of this before with 2005 340 Monsoon?? Any help will be greatly appreciated. Be Safe. THX Scott 815-651-7423 Also I`m looking for recommendations for a Tower also? One that is very user friendly, to stow everyday under my Shore Station?

[edwin]

vapor lock

[REW]

vapor lock

The issue is at the fuel pump. I usually prop open my motor box with a boat bumper or similar when stopping for a long break, lets in enough air to keep it from happening.

[srintx]

I have a 2005 Response LXI (340 Monsoon EFI). Just bought it this year. Low hours, Mint!! It runs great all the time? Last week we had heat index`s in the 100`s. We were on the Lake all week, so not so bad.. When we ran the boat for a couple hours, then had lunch or hit the sand bar for R&R. Then she would only turn over and put-out. (engine temp 160-170). Seemed like a Vapor lock?? Opened engine compartment, ran blower for 20-30 mins. Then she would run like nothing ever happened?? This happened 4-5 times last week?? Mechanic`s I talked to said an EFI shouldn`t vapor lock???? Has anyone heard of this before with 2005 340 Monsoon?? Any help will be greatly appreciated. Be Safe. THX Scott 815-651-7423 Also I`m looking for recommendations for a Tower also? One that is very user friendly, to stow everyday under my Shore Station?

vapor lock

Sound like Vapor Lock and yes it can happen with EFI

As far as towers are concerned I would do a search as it will show you many different topics. I would narrow your search down to Titan or Monster...the Titan line in now sold by Star One Wake.

to the CREW

[martinarcher]

A Star One tower looks fantastic on your boat. One of the guys at the recent WOW has a Star One tower on a Resonse LXI and it looks awesome!

I can tell you it is a rock solid tower! I've had two of them, and they are great. My second boat came with a Monster tower - if you like a tower the moved, squeaks, and rattles, a Monster is for you. . I promptly replaced it with a Start One tower and am a happy camper.

Here's the Response for our WOW! They had a black powder coated finish. It is also available in polished stainless steel.

Edited July 24, 2011 by martinarcher

[BuFootin]

I have a 2005 Response LXI (340 Monsoon EFI). Just bought it this year. Low hours, Mint!! It runs great all the time? Last week we had heat index`s in the 100`s. We were on the Lake all week, so not so bad.. When we ran the boat for a couple hours, then had lunch or hit the sand bar for R&R. Then she would only turn over and put-out. (engine temp 160-170). Seemed like a Vapor lock?? Opened engine compartment, ran blower for 20-30 mins. Then she would run like nothing ever happened?? This happened 4-5 times last week?? Mechanic`s I talked to said an EFI shouldn`t vapor lock???? Has anyone heard of this before with 2005 340 Monsoon?? Any help will be greatly appreciated. Be Safe. THX Scott 815-651-7423 Also I`m looking for recommendations for a Tower also? One that is very user friendly, to stow everyday under my Shore Station?

vapor lock for sure....cold damp towel wraped around the fuel pump for a few minutes will do the trick. Also, run the blower when you stop for R & R to cool the engine conpartment.

[db66]

We had the same experience at the lake over the Holiday weekend (4th) and again last week on vacation. Temps were 100+ every day, and the problem only surfaced after a 10 – 20 min rest following medium to hard running (wakeboarding, slalom, etc). After talking to several local marine mechanics who specialize in inboards (local Malibu and Mastercraft dealer), measuring and testing fuel pressure at the manifold test point, fuel pump outlet, and fuel pump inlet, I have determined the problem is a form of vapor lock but not typical.

A typical vapor lock is associated with carbureted engines and occurs when the intake manifold/carburetor heats to the point where the fuel in the carburetor bowls start to vaporize/boil. In most pressurized systems, like the EFI systems in most modern cars, this condition is not very common because the fuel remains under pressure from the time it leaves the tank until the time it reaches the cylinders. The pressurization significantly increases the vapor point of the fuel (decreases the boiling point), which eliminates or reduces the vapor lock condition.

Unfortunately, the EFI systems installed in our boats is a little different in the fact that the entire fuel line is not pressurized, only from the engine mounted pump to the EFI manifold and delivery injectors. In the auto application the fuel pumps are commonly mounted in or in close proximity to the fuel tank.

In most circumstances this is not a problem because the difference in height between the fuel outlet of the tank and the inlet to the fuel pump allows gravity and the weight of the fuel to pressurize the line but when certain environmental conditions occur (extreme heat, high altitude, etc) the pressure is not enough to keep the fuel from vaporizing. The result is the fuel pump will start to cavitate, which further exacerbates the problem by lowering the line pressure.

There are several factors that contribute to the problem; the increased levels of Ethanol in the fuel, insufficient air exchange to the engine compartment, and the lack of a primer pump installed in the fuel circuit (typically tank mounted).

Although Ethanol increases the octane level of gasoline it significantly reduces the vapor pressure, the point at which liquids turn to vapor (boil). In most cases if you are buying fuel from a marina the fuel will not contain Ethanol due to the negative water attracting characteristics but if you are purchasing fuel from the auto station you should be aware of the Ethanol level. I have been told that 91 octane is Ethanol free and 93 is 91 with Ethanol.

With regards to the engine compartment, when operating in extreme conditions I would recommend running your blower continuously while skiing, wakeboarding, or running hard for long periods of time. Propping the motor box is also a good idea as mentioned above. Anything you can do to lower the temperature of the engine compartment and especially the stainless steel line to the pump.

A couple of other suggestions that have helped our situation; I used exhaust manifold tape (header tape) on the SS fuel line to insulate it from the engine heat, and we also open the fuel cap briefly once the engine has been turned off to relieve any vacuum that may have developed. There is a vent line that should prevent pressure build up but I believe there is a check valve installed to prevent moisture ingress, which will not release under vacuum conditions.

I hope this helps and I apologize for the long winded novel version but I have spent the last three weeks trouble shooting this problem and if my experience saves someone else a little frustration then great.

As for the tower recommendation, we came across a real good deal on a Titan T3 and I could not be happier. The construction and design is flawless with all pressure points located on top of the gunnels as apposed to side mounts, which can cause stress fracturing and cracks. The assembly splits via two coupling joints that allow the forward loop to lay back against the windshield and the back loop to lay into the rear seat. The entire assembly is built from 2 ¼ stainless tubing that can be found in either polished or several powder coated colors. The tower works great with no obstruction to driver or creaks and groaning, which appear to be a common complaint with aluminum and side mount towers.

[MalibuNation]

Another good idea is if you are running hard let it idle for a couple of minutes b4 you shut it off ... watch the temp gauge to see if the temps do indeed cool down - if not ignore. I never had this probem until we went to corn gas ... grrrrrrrrrrr. Certainly open the engine cover.

Living on a lake we pretty go hard for long periods at a time and I never shut the boat off ... but sometimes someone forgets and shuts it off.

I have the LS1 and I also cool the fuel rails with a damp rag or shirt.

Also you might want to search this here or even Google it, "Mailbu vapor lock" if you want more info

[Jco]

Sounds like this could also be my problem. Does it make sense that topping off the fuel tank could also alleviate the problem? That is how I have gotten the issue resolved in the past, which has occurred 3 times this summer.

[Bill_AirJunky]

Assuming you ran the blower during/after fueling up, or possibly the elapsed time, or propped open the engine cover..... any of those may have helped get past the vapor lock.

I have a 340 Monsoon in my 05 Vride. Never had the problem till one particularly hot day in the mid 90s about a month ago. I usually run the blower a lot, probably almost 1/2 the time I'm out there. But this time the blower was off. We'd been cruisin around at idle speed for about 30 min. I shut the boat down to swim & hang out a bit. Started it up 10 or 15 min later & the boat would start, go 20', then shut down. Start, sputter, then shut down. I knew almost right away what it was from reading about all these guy's problems. So I pulled a rag out of the toolbox, got it wet in the cooler water, put it right on top of the fuel pump. I swear it wasn't 10 seconds later & the boat started & had never had a problem again.

Now I run the blower even more than ever.

[Steve B.]

Vapor lock. I think just about all fuel injected bu's are susceptible. I think ethanol in our fuels adds to it, so I make sure I put some de-ethanol stuff in the gas, and seems to help a little. Autozone 5 bucks or so.

But as said above, when you are going to sit for a few, prop up the engine cover a bit, start the blower 10 minutes or so before you are going to get going again.

I think it's partially becuase these engine covers are so inulated. Just like a car, after you shut them off, the heat goes up for awhile, and evidently mess's with the fuel rails.

Steve B.

Quick edit: I also found that reducing the thermostat from a 180 to 160 has helped just a little too.

Edited August 17, 2011 by Steve B.

[gige]

I have the same problem. 2006 VLX with a Monsoon 340. Boat runs great until you turn it off, does not need to be a very hot day either. But go to restart and it turns over, but does not fire. Let it sit for 10-15 minutes and it starts. Dirves me crazy. Thnking about taking it to the not so local Malibu dealer (who is a very good dealership) two hours away, but here in Pittsburgh the season is coming to a close soon enough, so will wait until we cant ski and wakeboard anymore. DO want to add that even when the boat is cold, the first start seems to turn over longer than it should before starting. Will do some more searches online and post any additional info I find.

Thanks to everyone who posted so far. Makes me feel a little better that others are having the same issues. Hopefully there is a good fix, love the boat, but this is a pain in the buttox. I dont have much time to play games with this boat and will trade it in for something else if it cant be fixed. Would hate to have to join the Nautique, Moomba, or MasterCraft forum next season. :-)

[Steve B.]

gige, just prop the cover up a few inches when you are going to sit, then run the blower for awhile before you are ready to go again. Ya, it's a quirk, but seems to end the issue.

Steve B.

[shawndoggy]

I have the same problem. 2006 VLX with a Monsoon 340. Boat runs great until you turn it off, does not need to be a very hot day either. But go to restart and it turns over, but does not fire. Let it sit for 10-15 minutes and it starts. Dirves me crazy. Thnking about taking it to the not so local Malibu dealer (who is a very good dealership) two hours away, but here in Pittsburgh the season is coming to a close soon enough, so will wait until we cant ski and wakeboard anymore. DO want to add that even when the boat is cold, the first start seems to turn over longer than it should before starting. Will do some more searches online and post any additional info I find.

Thanks to everyone who posted so far. Makes me feel a little better that others are having the same issues. Hopefully there is a good fix, love the boat, but this is a pain in the buttox. I dont have much time to play games with this boat and will trade it in for something else if it cant be fixed. Would hate to have to join the Nautique, Moomba, or MasterCraft forum next season. :-)

Gige, on a 2006 boat (and 2006 ONLY) you may also want to see what gauge wiring Malibu ran from the starter to the batteries. This is a somewhat rare issue, and I think limited to 2006 boats, but I had it and it acts nearly like vapor lock but it isn't -- it's a low voltage condition that's causing the ecm to tell the boat not to start. My experience with this issue is chronicled in this thread: http://www.themalibu...-an-hour-today/

there is a cheater temporary fix that makes it very easy to see whether it's voltage -- you stick a battery in the rear locker next to the starter and wire it straight to the block (ground) and starter (positive). As soon as I did this all starting issues on my boat completely and forever vanished.

Again -- just 2006 boats with starting issues.

Edited August 19, 2011 by shawndoggy

[Jco]

Ok, my problem is def. not vapor lock. I talked to the guys at my shop, and did what they prescribed to alleviate vapor lock, to no avail. They are gonna look at it when I take it in for winterization, but they now think I have a crack in the fuel pickup. When the fuel gets 20 gal. low, then it starts sucking air. I don't know anything about the fuel pickup in my tank, so I cannot speak to the likelihood of that being the problem.

[LS6Vdrive]

Ok, my problem is def. not vapor lock. I talked to the guys at my shop, and did what they prescribed to alleviate vapor lock, to no avail. They are gonna look at it when I take it in for winterization, but they now think I have a crack in the fuel pickup. When the fuel gets 20 gal. low, then it starts sucking air. I don't know anything about the fuel pickup in my tank, so I cannot speak to the likelihood of that being the problem.

I wonder why they cant design some louvers/vents/ram air cooling into the cover, maybe its a coast guard rule....seems to me i seen a photo of a M/C with a ram air scoop on top of the motor cover once.

James

[BlastRlxi]

I wonder why they cant design some louvers/vents/ram air cooling into the cover, maybe its a coast guard rule....seems to me i seen a photo of a M/C with a ram air scoop on top of the motor cover once.

James

You may have seen a MC with a scoop built into the engine cover. It was for a supercharged Prostar that they used for skiflying events if I remember right.

[Mommy and The Boys]

Thanks to everyone who replied. Defintely helpful. B safe Scott!!

[Joeprunc]

Reviving an old post. 

Something very similar happened over this past weekend to me, I was at Lake Shasta over the weekend, and it even back down when I was on the Delta yesterday.

I've been running the blower all the time now, but after someone skied and I cut the motor off, it took several cranks to get going again.  Some times I even cranked it for a good 5-8 seconds.  Thinking it was vapor lock I sometimes I tried giving it extra gas while in neutral, which sometimes helped and sometimes didn't.  It wasn't that hot and would happen sparatically.  It always started the first turn over of the day, or after sitting for a while.  After opening up the engine bay and starting it, it started everytime.  

While on the delta yesterday it happened again, and my skier noticed the rich smell of fuel once it finally started...I don't think its a vapor lock issue.  Its either an electrical malfunction (no spark), lack of air, or bad fuel.  I've ruled out fuel as I've had three fresh tanks from marinas, and gas stations and all have had the same results.  there is not a fuel water separator in this fuel system, so I cannot change that.  But I did pull my air filter (K&N style) last night and noticed how much crap was on it....I cleaned it and will give this a try this weekend.  Hope it cures the issue.

Also finally read Shawndoggy's post about a second wire to the starter....just funny how everything worked perfect up until this weekend.  Maybe I'll pull the cables and re tighten everything.

Edited August 30, 2016 by Joeprunc