2014 250 PROXS AIR COMPRESSOR VOLUME TEST

[99intimidator]

I have a 2014 250 proxs serial number #2B017902. I noticed a loss of about 600 rpms or more. I was checking the fuel and air pressure both are just a little low 90 psi on the air and 104 on the fuel. Then I did the air compressor volume and fuel pump test pinched off the air discharge hose no change both gauges stayed at the same reading. When I pinched off the fuel return hose the fuel pressure when up to 150psi. Swapped gauges pressure gauges same reading didn't see any fuel in the air side. Could this be a weak air compressor. I know one time it set a compressor overheat code.

[EuropeanAM]

Make sure you are achieving a good, solid clamp of the air return hose (watch carefully to make sure you don't mistake it for the water supply hose to the compressor... then run nearly side by side there).

If results are the same, I'd pull the cylinder head for the compressor, and inspect the piston & cylinder (no scoring present, check the REEDS for the air compressor). A weak or lazy reed (that doesn't close completely) will cause poor volume and perhaps even slightly low pressure.

Fuel pressure is due to the air pressure (FP= Air Pressure + 14 psi) +/- 1 psi.

[99intimidator]

I pulled the reeds and seen some scoring on the cylinder wall . Doesn't look like a lot of metal went through the system. I pulled the rails and injectors to send in and get them cleaned and tested.

[99intimidator]

Just found out all six air injectors are bad . Took apart fuel rail and found what looks like carbon buildup up where the diagram sits. What would cause carbon to build up there ? Really wasn’t a lot of metal that went through the system. New fuel rail ,compressor and now six injectors. I don’t know if it worth fixing.

[EuropeanAM]

Why are you replacing the rail? Surely not just due to carbon buildup (which is usually a result of direct injectors not closing between pulsewidth events). #1 cause is carbon buildup in the engine (oil, additives, fuel octane, fuel quality, excessive idling, other rich running conditions can all be contributors).

[99intimidator]

Just priced all the parts for the fuel rail and added what it was going to cost to test and clean the injectors. Figured I would be better off this motor was used in saltwater and has some corrosion.

[EuropeanAM]

Gotcha- corrosion isn't something that can be "fixed" here.

Keep in mind- new rails come with new FUEL injectors already mounted in the rails.

[99intimidator]

Replaced all the air injectors , compressor and fuel rails . I did the break in way of priming the oil system. I don’t know how much this limits the power . But what a difference the prop I had on was barely turning 5400 rpm before It was pulling to 6000 now maybe could have got more out of it had to slow down. What I thought was carbon in the rails turned to a rust color and when I blew the air supply line out it looked like rust came out of it too. What would cause that’s probably what went through my air injectors. I’m thinking about keeping it now just don’t want this to happen again.

[JOE54]

don’t want this to happen again.

that refreshing salt air that the compressor breathes produces moisture under normal operation, more salt =more rust ,solution =no opti or 4 strker

[99intimidator]

So the Optimax isn’t good motor to use in saltwater?

[JOE54]

they are fine for salt water just gota remember that the compressor uses the same air we breath salty humid air is just naturaly gonna rust things on any engine , harsh enviroment

[EuropeanAM]

+1

And if you end up with a leaking o-ring in the compressor, you'll end up with water in the compressor (which will also cause rust).