Motor Struggles

[Infishicated]

Engine Serial # 1B736246 2009 250 PROXS approx 282 hours.
2009 Triton 20X3, 10" bobs jack plate, dual power poles, and 4 agm batteries (3 bluetops troll, x2 group 31 for starting/electronics).
Fury 4 24pitch,
Currently pushing 5000 rpm, @ 55mph gps, when running good i get 5800 @ 69-74 depending on load. and really strong hole shot.
idle i am getting 2-5, WOT is between 20-25 psi
I have analog and vesselview mobile.

I been dealing with a this issue for almost a year now. it started last August, took off at blastoff and it was slow getting on plane. but otherwise fine. Then went to make a move and was unable to get on plane and was unable to get above 2000 rpms. Took it to the shop, had no trouble codes. we noticed an excess of sludge in the lower unit and oil was very burnt. So i the lower unit striped down and gone through and due to seals on backorder didn't get it back until this January. We thought I was over pitched as I was running a 26 fury 3 blade. In January the mech also replaced the oil pump as it had a leak ever since I have owned it. The tech river tested it and said it ran great and topped out at 74+ at 5800. I took it out and it ran fine initially, but after fishing for several hours it again wouldn't go above 2000 rpms. Had my battery checked, turned out it had a bad cell picked up on the load tester. warranty covered a new battery. then it ran fine for 3 months didn't see the results the mech did but also never had good conditions, then in may during a tournament i made a long run, quick hole shot and loaded down with my partner we were cruising at 68-70. Fished and then when going to make a move, got on plane like normal but then felt a hesitation or jolt. thought I hit something, shut it down and lifted the motor to check prop. it was fine and when i restarted it would not get on plane, limited to 2000 rpms. While on the long idle back to takeoff it briefly jumped back onto plane.

This time I took the battery back to be load tested, it was acting funny on the load tester, one iteration it was fine the second time it was not. They gave me another battery. I also went to but in a new fuel filter and had debris in the bottom. So I cleaned out the VST, purchased a new pump and replaced the fuel lines from the tank all the way to the vst. Including the primer bulb. went for a test run with the new battery. The results was a sluggish slow to plane, and could not not get above 5000 rpms.

Where do I look next, I checked the belt tensioner, when running at the console shows 14V. I am at a loss as what to do. Should I be looking at my coils? I replaced spark plugs and wires last year and have very few trips out with them. ALso what is killing these batteries, is this an alternator issue? fuel rail issue?

[EuropeanAM]

Suggest starting with the BASICS: Compression Test, SPARK TEST, Fuel Quality/Delivery/Air-Fuel Pressure tests. Maintenance History/Review and catch-up of all overdue maintenance (note that Spark Plugs ARE an annual item).

Timing light, connected to each plug wire one at a time while observing the flashing pattern can be a very useful tool if the problem is ignition related (suspect that it may be a coil, wire or spark plug breaking down when hot). May have to do this on the WATER, after the engine is acting up.

[Infishicated]

Thanks Don, I was in the process of checking the spark plugs and saw oil leaking down from the compressor under the pulley. Could this have an impact on my performance. Is this an early sign of failure. The pulley did have play in it. been a little busy to do too much else. Had a good amount of buildup or debris and oil on the underside of the pulley.
opti compressor (2).jpg

[EuropeanAM]

If you can feel and see play in the pulley (and can attest that the pulley retaining bolts are tight), the air compressor IS FAILING. It (and the return oil line filters) should be replaced, and it would be wise to have your fuel rails, hoses, injectors and Direct Injectors cleaned, validated, and serviced. Small metal fragments from a failing compressor can end up all through the air side of the system.

[Infishicated]

Update to my woes, took it to a local Mercury dealer. I had a bad coil #4 and low compression in #1 cylinder. This explains my loss of power this past year. looks like water got into it #1 somehow, we noticed a little water in the intake plenum also. We stuck a borescope down there and not sure how it has not exploded as of yet. The quotes for a rebuild/remanufactured motor is crazy for a 14 year old motor.

[Infishicated]

I am leaning towards repowering with a new 4stroke, but the 60+ week lead time is tough to bear. What is y'alls opinion on my current motor value for parts as everything minus the block and one coil is in excellent condition and no corrosion.

[EuropeanAM]

Sold as a whole, it's worth a lot less than the sum of it's major components (parted out). I'm hesitant to even suggest a value, since the repair cost/parts prices are climbing rapidly (and many are on backorder).