KAD 300 tick over slight surge/ rev increase

mattlidster

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Hi guys new to the forum so hello! I have a 2004 Fairline with twin KAD300's, the port engine has a strange surging which is worse when cold, it gets better when engine is warm and supercharger cuts out however it is still there, it sounds/ looks like it gets an extra shot of fuel and blips slightly then settles down, out on the water under load it all seems settled and both engines are spot on the number at WOT it just seems it happens on start up. I have had the injectors refurbed and also had an issue with corrosion in the old fuel pump that has also been replaced!! There was some sludge in fuel tanks and these have now been polished and the issue is less noticeable but if I listen I can still hear the slight increase compared to the starboard one that purrs like a kitten! Any ideas as there isnt a lot left to check?? Would the fuel pumps orientation make it do this, i.e is it a timing/ fuel delivery as I believe the pump is very slightly adjustable, is this like timing in a car? is there a special tool to make sure it is set up correctly?

Could it be anything else? I have swapped ecu from one side to the other and no difference the only thing left I can think of is could a fuel pipe have a issue or is it something more sinister in the cylinder?? The engine starts first turn of the key so I wasn't thinking a piston issue?

Any advice or help much appreciated.
 
Hi guys new to the forum so hello! I have a 2004 Fairline with twin KAD300's, the port engine has a strange surging which is worse when cold, it gets better when engine is warm and supercharger cuts out however it is still there, it sounds/ looks like it gets an extra shot of fuel and blips slightly then settles down, out on the water under load it all seems settled and both engines are spot on the number at WOT it just seems it happens on start up. I have had the injectors refurbed and also had an issue with corrosion in the old fuel pump that has also been replaced!! There was some sludge in fuel tanks and these have now been polished and the issue is less noticeable but if I listen I can still hear the slight increase compared to the starboard one that purrs like a kitten! Any ideas as there isnt a lot left to check?? Would the fuel pumps orientation make it do this, i.e is it a timing/ fuel delivery as I believe the pump is very slightly adjustable, is this like timing in a car? is there a special tool to make sure it is set up correctly?

Could it be anything else? I have swapped ecu from one side to the other and no difference the only thing left I can think of is could a fuel pipe have a issue or is it something more sinister in the cylinder?? The engine starts first turn of the key so I wasn't thinking a piston issue?

Any advice or help much appreciated.
The timing could be out , did the engineer have the specific tools to re time the pump,
Is the no 1 injector sensor connected ?
Carry out a lever calibration .
 
The timing could be out , did the engineer have the specific tools to re time the pump,
Is the no 1 injector sensor connected ?
Carry out a lever calibration .
Hi Paul yes the sensor is connected ok and no I don't think they had the right tool to do the timing.

Just out of interest are you down Poole way anytime soon? And would you be able to have a look at set up correctly at all??
 
Not managed to get down to film it yet as our mechanic is dropping down to calibrate pump now he has the tool, no she wasn't smokey.
 
Could it be the fuel pipe as you have said there was some sludge in the tank may have sludge in the pipe causing a slight blockage.
 
So fuel pump calibrated today and it hasn't made any difference! Testing the first injector resistance tomorrow as well as calibrating the lever.
 
Thanks for the update Matt. When you say you had the old fuel pump replaced, was that the Injector pump or the lift pump? Was it a new (£5,000) pump or a used one?

I'll be interested what today's testing reveals for you. Good luck!
 
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