Engine dies on hot days fuel design issue possible

"Well Suzuki has decided to in

"Well Suzuki has decided to install an inline pump on my boat as well. The only thing they can tell me is that it will be "several months" until they can get around to doing it. I asked them to just give a date any date as to when they will be here and their response was that they can not do that cause it is not their "priority" to have a service tech tide up for a full day on one boat, so they "will get to it when they get to it." Suzuki's customer service is junk and I'll will never buy another Suzuki. Also I asked about them installing another motor and his response was it wouldn't do me any good as all the new motors have the problem also and that for most of the motor "it's not a mater of if but when it will occur with them also".

Jason were did they mount this inline pump cause I only have two places that they could mount one. The 1st being on the rear deck (will not happen) the second being inside a non vented bilge area. If they want to mount it there according to USGC regs they would have to put in a vent system which means they would have to cut more holes in my boat. My boats brand new and I'm not sure that cutting random holes wouldn't void my warranty."

Jon I sent you and email.

Jon I sent you and email.

"Wow! I am sure glad that I fo

"Wow! I am sure glad that I found this discussion board. I am having all the same problems with a carb. 115 Mercury. It starts and runs great as long as it is nice and cool out. Starts and stalls when it is hot out. The local dealer tells me we are importing cheaper gas now (15% ethanol) I believe, and this makes the fuel in the lines evaporate in high temps.. He says that Obama is trying to get fuel with 30% ethanol imported and if this happens our motors will really have trouble.......But anyways, can you guys tell me if an inline fuel pump would help my Mercury as much as it seems to be helping the Suzukis? Has anybody had any luck insulating the exposed fuel lines? Thanks"

"Guys. I am having the same p

"Guys. I am having the same problem! I have a 2003 Suzuki 115 4-stroke. I run out to the ocean which takes about 45 minutes, turn off the boat to fish, and when I go to start it 10 minutes late it won't turn over. After waiting about 20 more minutes it will finally start. Due to the excessive "trying to start" the motor I ended up needing my ignition replaced. I have tried using Startron, and changed the fuel/water separator and nothing. The engine runs great, and long as I don't have to start it when it is hot.

Has anyone had any luck with Suzuki on a fix?"

Well About a month ago my deal

Well About a month ago my dealer called and said Suzuki was finally coming to install an inline fuel pump on the 10th of September. A few days before the 10th of September I called to make sure everything was good to go. Well as luck would have it Suzuki canceled and would not give another date for the repair.

So skip ahead to this past Tuesday and my dealer called and told me that Suzuki would be in next Wed or Thur to fix my boat. So I go to drop my boat off today since I'll be out of town for part of next week only for them to tell me that it is being rescheduled again! This time it's not because they don't have the fix but something about me complaining to much! Suzuki's customer service is the worst! Oh well back to the waiting game.

"Jon,

Man I really feel you

"Jon,

Man I really feel your pain if it's any consolation the inline pump seems to be working on my boat. I really hope this thread helps anyone thinking about buying a suzuki product make up thier mind about how "wonderful" they are to work with."

"Jason,

I hear you. I pers

"Jason,

I hear you. I personally like the motor when it's running but I would never go this route again. The lack of customer service is not worth the $900 saving I got over the other motor I could have bought."

"If all you guys would run the

"If all you guys would run the motor at idle after a run to let it cool down it might help. The next is to check the low pressure pump to make sure it is working properly since ethonal does attack the check valves & diaghpram. If the check valve is leaking all the vapor is pushed back through the filters & back to the tank. The inlet fuel line on DF90/115/140 comes in through the cover & runs behind the intake manifold and has a cover on it. Make shure it is routed correctly. Take hose off fuel rail cooler & blow compressed air to check if not cloged. Run engine with hoses off & muffs on water pick up check that there is water flow. If motors are not flushed properly these small hose wiil clog. I am a dealer in south Florida & I have not had any of these problems.There are cooler hose for front of engine to cool oil & block which should also be checked with same procedure. The suzuki manual has all the routing for all hoses in manual. [email protected]"

Ps Marthon gas stations sells

Ps Marthon gas stations sells gas with no ethonal here in south florida on land & all marinas sell gas with no ethanol

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Suzuki Tech came to the local dealer and worked on my boat and 3 others last week. They relocated the low pressure fuel filter, put a larger low pressure filter and "

I wonder how much money Suzuki

I wonder how much money Suzuki is going to waste and how many people they are willing to anger before they suck it up and just start putting on external fuel pumps like they did for Jason?

Qman were are you located? They were suppose to come and do some work on my boat but they put me off and instead they told me they were headed somewhere else.

"New Orleans.

Appears that

"New Orleans.

Appears that it is like Rollie Rose stated a while back, a source of heat is coming from the LP fuel pump. With a clear fuel line you can see vapor start to form at the pump. The pump is driven by a steel rod that rides on the cam. The heat appears to transfer through that rod into the pump and vaporizes the fuel.

Seems like a larger Vapor chamber that would hold more fuel for the HP pump would allow for the LP pump to work through the vapor that is created at the LP pump could solve the issue. Reason I say this is that I never have an issue if I just idel after a restart. Must give the LP pump time to catch up. The engine will run on the fuel that is in the vapor chamber for the HP pump. Just when getting on plane and running 4k rpms, it must use all available fuel in the vapor chamber and hit the pocket of vapor created by the LP pump.

It was also explained to me that there is a needle valve in the vapor chamber and it closes when the engine is not running. Guess this is what prevents us from being able to use the primer bulb to push out the vapor.

Was thinking about creating a cooler for the LP pump like Rollie Rose did, but the Suzuki has a plastic casing for the LP pump. Concerned that the heat is inside around the pump actuator and not sure how well the heat would transfer from the plastic to a cooler. Also there is only about 1 inch between the LP pump and the motor cover on a DF140.

Just putting some of my thoughts out. Been trying to do as much research on the issue as possible. Many things have had this type of problem, just wish Suzuki was more committed to solving the issue."

"As you can see from my previo

"As you can see from my previous posts, I have been dealing with this problem since my previous 2004 engine, 90 four stroke. The new engine does the same thing even though Suzuki tells me that they don't have the problem with their 90's. What I have done this summer that seems to help are these three things. 1-I found one gas station in Denver that sells non-ethanol gas that I used this summer. 2-I have used the Starbrite product previously mentioned on this site. 3-Once I run across the lake to my destination and shut the engine off, I pump my bulb until I build up enough pressure to make the bulb very firm. My thought with this process is that if fuel is vaporizing off at the pump, I'm building up enough pressure to not allow it to develop a vapor lock at the pump. So far in the temperatures above 80 this summer this has seemed to work, where previously it would predictably fail. You have to pump the bulb immediately after you shut the engine off, not waiting until you want to start the engine again. That doesn't work (I've tried it). I don't think you can get passed the vapor lock then. If someone else tries this procedure and it works for them also, I'd like to know."

Been waiting for the weather t

Been waiting for the weather to warm up to try your trick Eugene. Thanks for the information!

"I just stumbled across this p

"I just stumbled across this post today. I have a 2007 suzuki df115. I had the vapor lock issues on this motor since it was new. I am an auto tech. When a fuel injected car comes into the shop with the complaint of "hard start after hot soak" the first thing I check is fuel pressure. If a cars fuel rail does not maintain pressure with the car shut off the fuel will boil in the rail and cause vapor lock. I mentioned to the boat mechanic that I had symtoms of vapor lock and that maybe the fuel system was not staying pressurized. He said that because of marine applications that the fuel rail was not allowed to remain pressurized. (In the event of an accident, nobody wants fuel gushing about) The fix, as other have mentioned, is to install an inline fuel pump. Whether this is against marine regulations, I don't know. I do know that honda cars that were carbuerated (around 1985)used an inline, on demand, electric fuel pump that was mounted outside of the fuel tank. These pumps only put out 3 to 5 psi and they only run when fuel is being used.They work particularly well inline by the primer bulb because they maintain only 3 to 5 psi fuel pressure without constantly running. But I have to wonder if Suzuki knows this fix but maybe it doesn't meet regulation standards? You can raise the boiling point of antifreeze by keeping it under pressure, and likewise, you can raise the boiling point of fuel by keeping it under pressure. Back in 2007 I contacted Suzuki support and told them of my hard start problem. They acted like I was the only guy with this problem. I knew what was happening was inherent with the design and that others must be having similar problems. This thread proves it. Other possible solutions are to put a cool water line next to the fuel rail, or a fan that blows on the fuel rail when engine is off. I think I will contact Suzuki again and see what's up! (fuel pump fixed mine)"

"I have just finished rigging

"I have just finished rigging a new to me '05 DF 140 on my boat. I have no history with it yet but the engines are highly thought of in this area. The electric fuel pump seems to fix the problem for those in this thread that have tried it.

I wonder if there is any chance that the two in line pumps could over pressure the needle and seat in the vapor recovery chamber. This is identical to a float chamber in a carburator. I belive the vapor is dumped into the crankcase and will go to the throttle body via the blowby hose. Liquid fuel, if it were forced into the crankcase would not be good.

I am surprised that no one has mentioned the importance of a properly functioning antisiphon valve in controling vapor lock problems. Every built in gasoline tank in boats is supposed to have one at the top of the dip tube. For those not familiar with them, it is a spring and ball type check valve. It has two functions, to provide a small amount of resistance to the flow of gas so a leak from a gas line laying in the bilge, will not allow the gas to siphon out of the tank. The other never mentioned function is to act as a check valve to keep gravity, and pressure from vapor in the engine, from pushing the gas back into the tank. The antisiphon valve is often removed by well meaning folks who consider it useless. The valve also can be kept from working properly by junk from inside the tank. If I had a vapor lock problem, the first thing I would do is remove the valve and see if it is functioning properly. You should not be able to blow any air through it back in the direction of the tank. This will keep the fuel line full up to the engine and pressurize the line if any vapor is generated in the low pressure fuel system, which will reduce vapor formation. Once the engine is started the demand for fuel will open the needle and seat and allow the vapor out. The low pressure pump does not need to go clear back to the tank to find the fuel."

"Nelson Burkholde Jr. brings u

"Nelson Burkholde Jr. brings up a good point. I talked to my local boat dealer when I first had vapor lock issues about an antisiphon valve. They said that my boat didn't have or need one. They said that adding one could actually make the problem worse. I would have to disagree with them and agree with Nelson. I can blow easily through my fuel line right to my tank, indicating I don't have an antisiphon valve. Now I am curious if other suzuki owners with hot start issues have antisiphon valves in place?
I called Suzuki support today and asked them if there was a fix for hard starting after hot soak. They said that they are aware of the problem and working on a fix, but don't have one yet. I called my local dealer today also and they recommended removing the engine cover when stopped on hot days to alleviate the problem.(my boat is a 2006 Crestliner Mirage 17 ft with a 2007 DF115)"

I have a new antisiphon valve

I have a new antisiphon valve located at the top of the dip tube. I have tried it with and without an antisiphon valve and it still failed both ways. I have noticed that trying to pump the bulb firm after letting the engine sit for a half hour after shut-down is difficult to get it firm and doesn't make starting easier. I assume that's because I'm pumping against a vapor barrier that has had time to form. That's why I have started pumping the bulb firm immediately after shut-down. My dealer was going to put a one-way valve between the bulb and the engine so no gas could escape back even to the bulb but Suzuki said no to the idea.

""I called Suzuki support

""I called Suzuki support today and asked them if there was a fix for hard starting after hot soak. They said that they are aware of the problem and working on a fix, but don't have one yet."

Im sorry but that is such a bunch of junk. what they told you Brian is the same tap dance I got. They know the fix, but they are trying to make a cheaper fix i.e. make their own pump (info straight from Suzuki rep) that's why they aren't distributing yet. I can't believe they put the fix on hold until they tool up, man that buggers me mad.

As for removing the cowling after you stop, I would offer a word of caution. My son burned his hand because of me doing that, he was up on back deck fighting a fish, lost his balance slightly and caught himself by going palm down on the motor. Ouch!!"

pull the t-stat out

e-z

pull the t-stat out

e-z

i did not tell you this!!!!!!!!!!!!

"My issue still has not been s

"My issue still has not been solved as well. The place that winterized my boat told me it just needs new spark plugs, but I am not confident it is that easy.

I am starting to think my issue is not vapor locking. I had no problems in early July. The problem started mid July and continued into November.

Any ideas?"

Just-in-time. T-stat which yo

Just-in-time. T-stat which you did not say to remove. Will this allow motor to run cooler? or will it run hotter? I find my pee stream is never very hot compared to other motors that I have owned.

i was looking over the suzuki

i was looking over the suzuki manual today in search of my own problem and it said that you should not run your engine with fuel blended with ethanol or methanol that is blended more than 5%. i live in australia but i guess that there engines would be made to a world standard. there should be a one way valve in your fuel bulb

This fuel starvation problem in the Suzuki could also be related to vapor locking, caused by sun heating up the gas in the bulb.

Well, I had my first vapor lock problem with the '05 DF 140 I bought this winter. After a bit of drift fishing I started up and went to run on plane for home. The engine began to bog down so I slowed back to idle and the engine continued to idle. We pumped up the bulb until it was firm, and ran home with no problem. The bulb was very soft at first. I have a new antisiphon valve, so the problem seems to be an inability of the low pressure pump to clear the vapor. I did not idle after I started the engine. I will try that in the future.

Thanks to this thread I knew just what was happening and could quickly help the engine get rid of the vapor. If the problem is not corrected by idleing for a couple minutes after start up, I will replace the low pressure pump and if that fails, will install an inline electric pump. If one of you that had an electric fuel pump installed by Suzuki, could read the make and model # off the pump and post it on this site, it would be helpful.

Been watchin this thread for a while now. I have always had a "hard start" issue often after a hot soak with my DF 115. Never has been a problem--only a concern because the motor has to spin what seems, to me, an abnormally long time (more than five seconds) before it fires and runs. It always starts--it just takes longer sometimes.

Over the course of two years, I have had the motor bog-down twice and completely shut off once. In all these cases the motor had set for a while after being run, it was hot out, and the motor either bogged out or in the one case died (shut down completely) just as the boat was getting up on plane. In all three cases, pumping the bulb got me back up and running again.

I've not heard any more about a "fix" from Suzuki. Some guys have had the inline pump put in, but has Suzuki stopped doing this or have they developed a new "fix"?

We have had the same problem with the 2008 DF115 on our pontoon. Suzuki finally agreed to give us a new motor 2010 DF 115...guess what....SAME PROBLEM!!! After finding this website and reading all of your complaints, I printed out some of these and gave it to our dealer who contacted Suzuki about installing an inline fuel pump. Suzuki said they would do it but out dealer says it is a noisy pump. So my question is to all of you who have had this done...How noisy is it? Our motor is very quiet when it is running, now I am worried about the noise if I get this "fix" done.

Picked up your problem today. Have similar problem with my Suzuki so when you say you fitted an in-line fuel pump. Did you take the old one out and replace with new or have you kept the old one and added another one i.e. do you now have 2. If so where did you put it? Thanks

Well, at the end of last year I fabricated a low pressure fuel pump cooler. Due to the mess with BP in the Gulf I hadn't taken the boat out until this past weekend. The air temp was in the mid 90's and water temp was even hitting 89.
These conditions normally drive me crazy with the vapor lock issue, but ran the boat for 3 days (about 24 “hot soaks”) and only had one problem after a hot soak. The one time it occurred was after I had ran the boat for about 10 minutes at WOT then a about 5 minutes idling up to a fishing spot before shutting down.
This cooler was only a test and intend on refining it, but this is what I have so far. I fabricated the cooler from a computer heat sink that was designed for water cooling. The head sink is notched at the top for tubing. Pulled the original short piping off and ran some ¼ inch tubing across the top, made a loop and ran it back across the top. Put thermal grease in the slot for the tubing then flattened the tubing a bit to get extra surface contact. The tubing is fastened place with some JB weld. The water from the pee stream isn’t the coolest, but spliced into that line to provide water for the cooler.
Put additional thermal grease between the top of the fuel pump and the base of cooler and attached it with some 230# single strand stainless wire. The heat sink had mounting holes in each corner which I s***** the line through and around the back of the fuel pump only having to tie it once.
Will try to attach a picture of it.
If I can make this from some left over computer parts, Suzuki should be able to do much better!

The typical electric fuel pump is a selenoid operated diaphram or piston pump. There is a continuous thump-thump-thump as the selenoid takes each gulp of fuel. The pumping is actually done by a spring and a couple check valves. The strength of the spring determines the pressure the pump puts out. I don't know which pump Suzuki uses, but I believe it is installed in series with the diaphram pump on the engine, so I would guess a low pressure variety would be best to assure that the combined pressure does not over-pressure the needle & float in the vapor elimination chamber on the engine. I have a similar pump on another boat in a fuel polishing system. The noise is tolerable if it is mounted below decks, but the Suzuki is so quiet at idle that you would likely hear the pump at idle, but not likely with the boat on the move. The pump would surely be activated only when the key is on.

I would love for someone who has had the Suzuki installed pump to tell us what pump was used and how it was installed. It seems like once the pump is installed, the folks stop reading this thread. I guess that says it is a satisfactory fix.