2018 18 TRX 200 Pro XS Loss of 5mph Top End Speed

[barmour]

losing a few mph top end

[EuropeanAM]

-removed both thermostats and they both open on stove pot just as water starts to boil.


-I removed lower cowling and found a bleed cover screw and a long 4 inch long slightly angled boomerang metal piece and its 2 allen screws and a cracked off metal cable holder from it that I could find where they came from, looked like they hold some wire stuff in place but not sure where from.

I've now read through most of this story (as well as a conversation about it) 3 times. While some of the information is useful- what happened with other boats having a completely different engine has very little bearing on this problem. Respectfully: It simply makes it less likely that someone will read through ALL of the information. Please take the time to edit and remove those items so that information not pertinent to THIS boat doesn't have to be reviewed over and over.

The BOLD RED in the above quote is a problem. Water boils at 212 degrees F. Your thermostats should open at 130 degrees F. They should be completely closed by 110 Degrees F (with no discernible leakage past the valve).

Please provide a picture of the "bleed cover screw and a long 4 inch long slightly angled boomerang metal piece and it's 2 allen screws and cracked off metal cable holder from it".

As we discussed previously- those Warning Horn occurrences are an indication that there is a problem with your engine that needs to be addressed. Once the horn has sounded- it ceases and ENGINE GUARDIAN takes over (limiting your available power). You will need to determine what fault is occurring either by having a DEALER get the engine on the Computer Diagnostic System, by obtaining your own scan tool (such as the Diacom System we discussed), or by observing the faults on your Vessel View Mobile setup, once it is installed.

I would not do anything else (or even run the engine) until ALL of the above are addressed.

Don't forget the pictures... that long statement about loose pieces and hardware is very concerning.

[barmour]

got it, tks

[EuropeanAM]

Ok... the "Boomerang" piece (and the two small bolts with 8mm heads) are supposed to be installed in the PORT/FRONT of the lower cowling, to retain the rigging flange in place.

The clamp (which incidentally is broken) may have been at the bottom of the intake, on the oil supply line just AFT of the oil pump, or in the back retaining part of the Coil Harness (I suspect this last one).

Connect the Brown w/White Stripe wire to the Brown w/white stripe wire (they are intended to be plugged into each other- that is the TRIM SENDER.

[barmour]

Copy that. Tks D

[barmour]

NA

[EuropeanAM]

That is the throttle position sensor. It is isolated on rubber mounts and should not be contacting any hoses/wiring/etc (nor should anything be contacting it, as that can skew it's function significantly).

The PCM uses it as a primary input to advise what the commanded throttle position is.

[John Jackson]

IT is hard to read. Did you check your oil level on the inside cowl oil tank? Even slightly low will reduce RPMs and power.
Have you checked for WOT with someone pressing the hotfoot all the way. Sometimes the screw stop on the hotfoot moves.

[barmour]

oil leve good

[Bob G.]

For peace of mind, I'd replace all fuel hose from the tank to the pulse pump and put the primer bulb just in front of the transom with enough slack so that you can point the arrow up to prime.

3/8" Mercury fuel hose from tank to primer bulb and 5/16" from primer bulb to pulse pump is normal. Grey with blue print.

[barmour]

ok tks

[EuropeanAM]

Yes under cowling oil is at top cap. I wedged a pole between hot foot and pillow and checked the 2 square metal throttle rectangular pieces(forget the names)in on motor were .025 and backed out hot foot screw 2 turns and made no diff. I forgot to mention lately like 1 put of 5-10 times, with motor warmed up and a long no wake zone idle, as you floor out of hole just before front starts to break over the engine spots and sputters, loss of all power then throttle back and start over and normal? As if lost all spark or gas but only once in while. Don, does a new 2018 Triton fuel hose from tank to motor black hose normal. Does Triton choose fuel hose or dealership rigging? Whomever installed my fuel ball put it way back under rear decklid and have to scratch heck out of arms to the elbow to pump ball. I've actually never had to pump the ball but once in 2 years until last years once last fall when motor quit after few runs motor stalled and wouldn't start until found fuel ball and pumped it. Is black hose before bulb still being used on new boats? Should I be concerned of black hose pre ball pump?

The hose from the tank to the bulb "should" be ok in a 2018 Triton- but you can only determine that for yourself. Physical inspection and verification by you is the only option, other than complete replacement.

No special tools required to install bulb or line, fuel filter tool would be a wise investment, though. Pulse pump requires normal hand tools.

Best to keep bulb inside back deck if possible- it protects it from sunlight.

While your "500 hrs" motor was also rigged with a fuel line splice outside the cowling, it makes sense to eliminate the splice- which eliminates a potential restriction AND leak point in the process.

Your engine had that black hose for "ease of rigging purposes".

BTW... primer bulb really should be pumped firm before each engine start. The warmer the weather gets- the more critical this becomes.

[barmour]

got it

[EuropeanAM]

Brown w/white stripe wire would NOT result in a fault (it's analog, and not monitored by the PCM).

[barmour]

tks

[SilverFox579]

Don's recommendation is pump bulb firm prior to EVERY engine start as today's fuels will vaporize in the line. Another possibility is your pulse pump may be weak, if you have any doubt, kit the pulse pump.

[barmour]

ok tks

[SilverFox579]

I'm out, you can wait for Don.

[barmour]

ball pumping several time a day?

[Savage]

Gas is NOT being supplied to the VST sufficiently.

Causes could be any ONE, TWO, THREE, or ALL of these things listed below:
Fuel Demand valve.
Pulse Pump.
Vacuum leaks (worm drive hose clamps)
Collapsed liner inside the fuel lines.
Primer bulb.
Fuel tank.
Cheap parts installed incorrectly.

BTW SilverFox579 is SPOT ON in his comments.