2014 225 ProXS stumble / stall when cold

[NJfishinGuy]

I have a 2014 225 proXS serial number 2B011330

Engine has 120 hours. sat for a some years in storage till i went over the whole thing. injectors were serviced by brucato, everything cleaned out and filters changed. tank drained and fresh fuel and lines. engine runs excellent except for one small hiccup i don’t quite know where it’s coming from. when you first fire it up, it sometimes has a very slight stumble for about 30 seconds. a little longer then it takes for my smartcraft gauge to run its check. if it’s put into gear it sometimes stalls. after maybe 30 seconds it smooths out and idles fine and runs perfect otherwise for the remaining time it’s running. if i shut it off and start it, it’s fine but if i’m fishing for a while and then go to move it will do it again.

i just checked the tracker valve & air diaphragms all of which look like new. idle is 580 +/-20rpm

Any pointers what to check?

[lpugh]

Spark plug and properly gapped?
air/fuel pressures at 1000 rpm and for 15 sec after shutting down?
fresh 87 octane fuel?

[NJfishinGuy]

I will double check the spark plug gap today. The fuel is fresh and I also need to check the fuel pressure pressures. Do you happen to know what they are supposed to be?

[lpugh]

air 94, fuel 109

[Savage]

I would check the throttle plate air gap also.

[lpugh]

^^^^^^Yep

[EuropeanAM]

+3

MUST be .093" (Precisely) at the highest point of the throttle blade (90 degrees from the throttle plate shaft, and closest to the flywheel).

What FUEL and ADDITIVES are you running (be very specific)?

[NJfishinGuy]

i have been doing the 150:1 oil mix in the fuel. i’ve religiously run seafoam for many years in all my boats. recently picked up star brite ring clean+ . i’ve only had about 30 gals total run through since i got the boat and went through everything. i plan on getting the quick clean to use. i did realize i never changed the plugs and they are a bit fouled and gapped at .40. to get oil moving after sitting years i put the engine into break in mode not having a scan tool to prime the pump and planned to change them after the double oiling was finished. over the winter it slipped my mind. new plugs are on their way and i will gap to .042-.043.

on a side question. for the tracker and air/fuel diaphragms . how is the center suppose to be oriented. it’s got a flat side and a round ball side. the lower on the port rail was flat side toward he rail and the top one with the heavier spring air regulator was round side toward the rail. i did slip and drop this one when removing to inspect and i’m not sure if that’s the proper orientation or it spun when i dropped it. i’ve seen pictures both ways so i want to confirm orientation. i attached a generic picture to show what im referring to.

[EuropeanAM]

Flat side toward the rail. If one was turned to the round side, REPLACE it.

See the FAQ Section, "Fuel, Oil, Batteries, Spark Plugs, Fuel Additives...." post. Strongly recommend sticking with the suggestions there for best results.

[NJfishinGuy]

stupid question but is the air gap to be checked with the engine off or running? i really can’t imagine it would be while running but i’m just surprised how far out the adjustment actually is on a engine with only 123 hours. i just checked it with it and im well below .093, around .073 which is why im questioning myself. if this is correct though what is the proper way to adjust it? appreciate the help. in a pinch here to get it right as i’m leaving for a week fishing trip vacation this saturday.

i’m assuming it’s just a matter of loosening the cam roller then adjusting the throttle blade screw with the locknut then just readjust the cam roller. missing anything?

i attached a picture of taking the measurement. just want to confirm i did it correctly.

[lpugh]

not the roller, adjust with the stop screw for closed position, then check the roller clearance, roller should have about .010 clearance at closed throttle this allows for a little tps increase before the throttle blade moves

[JOE54]

^^^^^^ yep

[NJfishinGuy]

perfect thanks.

[EuropeanAM]

In many cases, you have to dig about 1/4" of blue epoxy out of the screw and off the nut. Since it's an allen-screw, I strongly recommend removing the throttle plate and applying some heat to the bottom of the screw so as to break the threads loose without stripping the allen.

Sometimes they were improperly set, sometimes the screw banging against the aluminum stop ear wears a divot that affects the gap.

Good catch!

[NJfishinGuy]

i used a pick and was able to remove the epoxy fairly easily. Made my adjustment. adjusted the roller with .010 clearance and took it out for a run. almost complete improvement in the constant stumble at idle in gear. only thing that still remains is a intermittent stall when it’s put in gear for the first time after initial startup or if the boat is shut off and sits for a few. sometimes a stall sometimes a stumble and recovery. then it’s fine again. runs fantastic otherwise all around.

i seen an older thread about an almost identical issue and the guy also had the air gap to tight and afterwards he ended changing coils and wires and it resolved the rest of the issue. i’m gonna check fuel pressure and how long it maintains that pressure as soon as my gauge comes in.

[lpugh]

dual glycerin filled gauges required, must have air and fuel pressure at the exact same time, a link a video would be very useful
using 87 octane fuel?
and the cocktail?
if not double does the quickleen for one tank, 4 oz for 10 gallons
I have seen some that start using it clear this type of problem
having set with bad fuel in the system, might consider having don clean and validate all the injectors

[EuropeanAM]

I would try the above suggestions for the cocktail (double up for a tank) and follow up with a fresh, properly gapped set of spark plugs. I've seen plugs fouled from a narrow air-gap in less than 12 hours.

[NJfishinGuy]

the injectors were done by rich at brucato last summer. they have about 5-6 hours run time on them currently. the fuel system was gone through completely at that time before i ever started this engine. (it sat in storage since 2017). i just put new plugs in. have about 30 mins run time on them. gapped .042 i will get some merc cleaner and try running that also though

what’s the best place to get a set of the proper gauges? i’ve read a set of automotive ac gauges could work with the right adapters. any truth to that?

[lpugh]

i put together my own gauge set with top line parts, steel braid hoses, glycerin 4in, 1% accurate gauges, correct fittings and hose adaptors were the hardest parts to find, tool dealers can get the Ford adaptors for you,
20250425_064917_resized.jpg

[JOE54]

those are nice LEON