Suzuki DF115 Starving for fuel @ high rpms

[emo]

I have twins ....one is starving. I have replace everything from the pickup tube to the low & high pressure pumps, Bulb, filters, Fuel regulator, lines, clamps, It runs fine at low RPMS. Same tank one pickup tube. When I put a t in the other engine and by- passed the high pressure system and hooked direct to the fuel rail injectors the engine runs fine @ high rpms. Injectors seem to be working fine. Anyone have any ideas???? Please Help!!! Thank You!!!!

 

[reeldutch]

Re: Suzuki DF115 Starving for fuel @ high rpms

did you Check the fuel pressure ?

high and low

 

[emo]

Re: Suzuki DF115 Starving for fuel @ high rpms

Installed new low and high pumps. I did not know how to check the pressure.

 

[silentbob]

Re: Suzuki DF115 Starving for fuel @ high rpms

I am having same problem. I have replaced injectors and VST. I am now thinking it is a electrical prob.

 

[smallconsolation]

Re: Suzuki DF115 Starving for fuel @ high rpms

I am having same problem. I have replaced injectors and VST. I am now thinking it is a electrical prob.

I am having the same issue
with my 2005 df115.450 hours 2.5years on the boat. It is in the shop right now,and the dealer techs want to change all the filters at $500.00 +. they could not replicate the problem after a 15 minute joyride,and the computer is showing no problems. I took it out for a ride this am and within a half hour of wot the engine rpm was all over the place .I gave them permission to run the boat till the problem is replicated. Has anyone figured this out yet? This is my 2nd suzuki in 7 years. the first was a 2003 with the exhaust problem.
This will be my last suzuki.

 

[smallconsolation]

Re: Suzuki DF115 Starving for fuel @ high rpms

same problem 2005 df115 450 hours . any cures?

 

[99yam40]

Re: Suzuki DF115 Starving for fuel @ high rpms

http://forums.iboats.com/showthread.php?t=250876

 

[clanton]

Re: Suzuki DF115 Starving for fuel @ high rpms

Why don`t you connect a fuel pressure gage and run the boat until problem show up. Looks like no one checked the fuel pressure regulator. Battery termials clean and tight. I don`t understand how you bypassed the high pressure system and made it run, but if it ran, then the problem is in the high pressure. Sear has fuel pressure gage, with fittings ACE hardware, fuel hose from NAPA. you will have a gage to check pressure. Long fuel hose will put he gage in captain seat. 36 pounds fuel pressure.

 

[smallconsolation]

Re: Suzuki DF115 Starving for fuel @ high rpms

Well,the marina called back.yes ,they replicated the problem. They still think it is the vst filter. I suggested that the could change it. If it doesn't cure the fuel starving issue, they owe me.... We will see.

 

[stylesabu]

Re: Suzuki DF115 Starving for fuel @ high rpms

its either heat or a filter. did this problem occur overnight? one day next day a problem? or did it start up at the begining of a new season/ If its a filter it will get worse, meaning now its about 1/2 hour before it acts up, soon 25 minutes then 20 minutes and so on. if it always seems to 30 minutes then something doesn't like the heat, but you have to try to run it under same conditions. are each engines fuel being filtered by same filters? also if its only 1 motor thats acting up, and they are identical. yo can switch parts until you find which one make the other act up.

 

[clanton]

Re: Suzuki DF115 Starving for fuel @ high rpms

Smallconsolation

You don`t have to guess at these problems, if you move the fuel pressure guage to different spots in the fuel system it will show the low pressure point. The VST has 4 parts inside , fuel pump, pump filter, fuel regulator, and float assy, all can be bench tested. fuel system will not show on computer or red lights, no sensors on fuel system. Fuel system should have a Raycor primary filter. High pressure fifter has steel case, if have water in system case will rust inside at the inlet and outlet. Rust will flake off then goes to the injector. Water also causes the injector rail to corrode. Mechanical fuel pump must have correct pressure to pull full from tank and push to VST.

 

[smallconsolation]

Re: Suzuki DF115 Starving for fuel @ high rpms

Dealer did all of the above. Replaced fuel reg, rebuilt injectors replaced all filters,i installed raycor filter. New fuel.dealer suggested phase separation ,which caused debri ,which clogged injectors cost$1k. Relaunched,1st hour out no problem. Suddenly red lights ,code 43[fuel injectors} made it back to port,back to dealer.they found one fuel injector harness connector had worked loose. I must have done it!!!! Supposedly ok now .will test tonite and let you know.

 

[clanton]

Re: Suzuki DF115 Starving for fuel @ high rpms

Thanks for the heads up. I here some reports of more then 10% alcohol in the fuel, seen some test kits online. Here in Panama City you can buy fuel without alcohol. One other thing you should check is the propshaft bearing housing for corrosion between the housing and the gearcase. The corrosion will split and ruin the gearcase. This is a service item in service manual.

 

[Relyt]

Re: Suzuki DF115 Starving for fuel @ high rpms

Can I ask what the solution was to this problem? I am experiencing similar problems.

Thanks

 

[clanton]

Re: Suzuki DF115 Starving for fuel @ high rpms

Relyt,

After you replace the defective parts, new filters, Rayco primary filter, clean fuel tank, clean fresh fuel, do not let for 2 months. Keep tank clean, you should not have a problem. If you have the VST off try to enlarge the drain, and drain the VST now and then.

 

[Relyt]

Re: Suzuki DF115 Starving for fuel @ high rpms

Thanks for your help, problem solved. I got lucky in that it was the fuel filter part number 15440-93J00. This is the filter before the VST. I do not think that this part is a recommended PM part, that being said took 5 minutes to replace. Felt good running at full strength again tonight.

 

[Relyt]

Re: Suzuki DF115 Starving for fuel @ high rpms

I thought the problem was solved by the above, turns out I was wrong. The screen inside the VST was full of junk. I replaced this pencil eraser sized screen and the motor has run great since.

I think a lot of dealerships will replace the entire VST when this is going on. The part I replaced cost 7 bucks!