Not sure if anyone here knows, but hopefully someone has an idea.

My motor has been running fine, but today if felt like I had a boat full of water. The motor struggled to get on plane and when it finally did, it was about 12mph short of regular wot speed. I pulled the fuel filter and it looked clean, where should I go next?

Compression test?

Plugs and wires? Having a hard time finding the part number for wires, if anyone here sells them, I’d like to order some.

Could it be a bad coil?

Just looking for some guidance, other than go to the shop, I know the wait will be crazy long right now.

Might need pressure test on Fuel rails, and also might need injectors clean ,

Instead of overthinking it why not check the simple things first? Motors have 3 factors that make them run. Spark, compression and fuel. Any one of these things can give you the issues that you are experiencing. Do you have spark on all cyl. do you have good compression. If these things are within specs. then that leaves only fuel. Lose of spark on a cylinder can be several things. Bad coil, bad spark plug, bad computer. Bad compression is the worst. Requires motor rebuild or replacement. Fuel issues can be a multiple of things but are repairable.
Do the progression, 1. check for spark, 2. Check compression, (if this is bad you can stop and go have your self a good cry, your days of fishing are done for awhile) . If these things are good then you can concentrate on then fuel management.
KISS is the best idea.

Check fuel lines and bulb, this [censored] gas can cause them to collapse internally. Did you check/drain water from separator? Might need to pull filter/pump housing and clean inside. Any alarms?

Check spark plugs. Mine did this and had a bad spark plug. Fouled up beyond belief. replaced all of mine, motor was back to new. 15 minute job and been good ever since.

Starting with plugs, wires, fuel filter, new bulb & new belt on top (I know the belt has nothing to do with my problem), these simple parts come in at over $400, insane how expensive everything has become. I’ll check compression next time and then search YouTube on how to test fuel rails.

Also check all the hoses under the cowling, on my Optimax I found a cracked line going into a fitting on the fuel rail and a hole rubbed into an air line that got too close the the flywheel....

I’ll look around.


I read something earlier that some gas stations are now using 15% ethanol in the fuel, don’t think it’s my problem, but I do need to check the stations pump.

Check fuel lines going to filter. I have an 04 optimax that starting running sluggish and fuel line was coming apart inside and stopping fuel flow to filter and pump. Had very little evidence in filter. Put new fuel line from tank to bulb to motor and all was well. Hopefully this is problem. Easy check. Just pull fuel line from bulb to motor and you can tell if thats the problem.

This is actually what it feels like, starving for fuel. I might as well replace the line and be done with it too.

I had the exact same thing happen to me a while back. Forgot to put the plug in the boat...transom well filled with water. Trying to get on a plane to drain the water, motor ran about 500 RPMs short of top end. Once water drained, motor still struggled with top end RPMs and speed. Problem was a bad fuel injector. Replaced fuel injector, replaced fuel lines and all is well again. Not sue how dogging the motor with 500 lbs of water in the transom well would cause a fuel injector to die. Regardless, that was the problem.

I suspect the ethanol in the fuel over 10 years of use ate up the inside of the fuel line. When enough of that material landed in the #1 fuel injector, I had an issue. Recommend pulling all fuel injectors and send them away for cleaning. Then...replace all the fuel lines in the motor. Then, never use ethanol fuel again.

Fuel pump, fuel lines, coil packs, spark plugs, id start with the fuel pump and lines.

If you can even find them! A lot of the stuff that’s only available on the OE market is on back order. Finding parts for anything is a scavenger hunt every time these days. With the plugs and fuel filter I do know you can find them online aftermarket for cheaper. The plugs for that are an ngk plug that you shop be able to get at an auto parts store. Coils for those boats are outrageous though!

Be careful if you buy plugs online. Lots of counterfeit stuff out there in the iridium plugs.

oriellys has a marine parts division, I buy plugs at rock auto now and save a bunch on them