New Suzuki DF115 losing Revs/power at higher speed

[dogfish69]

Hi,

I have a new DF115. The motor only has about 20hrs on it. I imported the motor into Australia from the USA with a new boat. For warranty work they say I must send the motor back to the USA - so for now that's not an option I'm going to consider.

At revs up to 4000rpm it runs perfect. at revs over 4000rpm after about 5 - 10min it starts to lose revs. The revs drop to about 2000rpm then back to about 4500rpm in a second and it keeps doing that until I pull back on the throttle. So far I've tested the petrol tank breather, changed the water separator filter and the local dealer change the internal motor fuel piping with a better quality stuff.

Has any one had a similar problem and what do you suggest I try next.

Thanks
DF

 

[JRJ]

Re: New Suzuki DF115 losing Revs/power at higher speed

Sure sounds like fuel or air. Bulb doesn't collapse? Changed the small light blue engine fuel filter? Fuel is good? Checked fuel for water? Added any injector cleaner? I'm not a wrench, I used to own a DF115 and loved it. Buy a Suzuki Service Manual for your engine if you don't have one. I bought mine from http://www.brownspoint.com Good luck getting it sorted out, great motor.

 

[stylesabu]

Re: New Suzuki DF115 losing Revs/power at higher speed

try enriching fuel mixture when this happens. use a can of spray carb clean near fresh air in let or you can use propage attached to a hose.It sounds like your starving for fuel. let us know what happens when you do this, and i can point you in the right direction

 

[sean whiteman]

Re: New Suzuki DF115 losing Revs/power at higher speed

yep i will be a fuel issue.

 

[reeldutch]

Re: New Suzuki DF115 losing Revs/power at higher speed

when was the last time the high presure fuel filter was replaced?

the fuel pressure should always be around 35 psi.
when you go wide open the resistence of the clogged high presure fuel filter will drop the presure .
when you bring the engine down presure builds up quickly because there is less demand and engine runs fine.

change high presure fuel filter, drain and flush vst.

i would start right there.

if you have a fuel pressure gauge you could verify the problem by T ing it in after the high presure fuel filter.

it also could be the regulator but they never go bad.

 

[k4ubr]

Re: New Suzuki DF115 losing Revs/power at higher speed

fuel pressure should always be around 35 psi IT NEEDS TO BE CHECK AT THE RPM THAT IS HAPPENS AT... IF FUEL PRESSURE IS GOOD IT WILL BE YOUR INJECTORS.......