Mo-Powah SX190 Flame Arrestor removal

[blacksapphirez]

so I got brave and tore up my engine... na it wasn't that bad. just removal of the air filter and throttle body. I saw the AR190 write up and thought i have to remove the entire intake manifold but na our's is bit easier. 13mm and a hex bit

that flame arrestor is in there very tight...had to fight a good bit to get it out without damaging the aluminum intake manifold... but gained 2mph and 200~250rpm. Very quick BUT...cavitates out of the hole. may need higher pitched impellers ...

 

[DBamaC]

You are a brave man. I'm not sure I'm there yet. Glad to know you are nearby in case I get my nerve.

 

[SamCF]

Very nice! I didn't realize it was so easy to do on the 190's. What GPS app are you using?

 

[swatski]

Did the same couple weeks ago - the ribbon delete on my 2012 SX190, following a write up on the other site.

Huge difference - worked out great!

I'm pretty much at sea level. The boat was doing about 7600RPM and 43-44mph before. With the ribbon deleted (stock filter in) - I'm hitting the rev limiter at 7800-7850RPM and the boat runs 47mph for as long as I want (phone GPS; boat speedo maxes out).

The ECU seemed to have automatically adjusted for the added air, and the boat feels MUCH happier, it is snappier and sounds better.

I was actually surprised how well this mod (unmod) worked.

Speedo maxed out (47mph on GPS), 7800RPM on digital tach. Please ignore the depth gauge... I did NOT do it in 1.7 ft of water

 

[blacksapphirez]

question... how did you @swatski get the gas gauge to come up on top? I haven't really messed with the gauge except to scroll through all the stuff...
I can only get it up to 7600rpm and I think i briefly hit 7700...

@DBamaC lets do it! only takes 30minutes or so

@SamCF it says GPS Speedometer Free... i think there are quite a few with that name though lol

BELOW are videos...click to view

 

[swatski]

@blacksapphirez don't know about the fuel gauge...... will have to look it up on the boat later in the week... hope I can backtrack...

After my ribbon delete I could see 7850RPM, but it would toggle back and forth to 7800. The boat felt like it wanted to keep going... Not sure what I did, bimini up or down didn't matter.
That was BEFORE my impeller/wear ring upgrade.

 

[Big Shasta]

Seems like you would surely want a fume detector with that gone.

https://jetboaters.net/threads/how-to-install-a-fume-detector-with-blower-control.20/

 

[blacksapphirez]

@swatski do you think your boat was over revving because the wear ring was worn? looks like same mph at 150~rpm more.

@Big Shasta I don't think its necessary... blower will take out any fumes and stock filter will be another barrier...not that it will stop it. but after the engine is on, its sucking in air ... so i would turn on the blower only when i am starting just like i would on any boat

 

[swatski]

@swatski do you think your boat was over revving because the wear ring was worn? looks like same mph at 150~rpm more.

@Big Shasta I don't think its necessary... blower will take out any fumes and stock filter will be another barrier...not that it will stop it. but after the engine is on, its sucking in air ... so i would turn on the blower only when i am starting just like i would on any boat

@blacksapphirez Don't think it was the case, both OEM impeller and wear ring looked new upon removal. But the boat had only 30 hrs in fresh water - so no surprise there. I could barely move the impeller inside the wear ring. I do have cavitation that I'm trying to solve with the new impeller, custom pitched Solas from Impros.
Could it be the limiter settings?

@Big Shasta Like @blacksapphirez said (x2 here). Many users have done that mod, especially in the jet ski realm, RIVA RACING has a "kit" for ribbon delete, just a plastic ring to smooth the air flow, no mention of problems. I have read an opinion that the CG flame arrestor regulations are somewhat outdated and it may be a bigger issue with carburated systems. That said, thank you for the link to fume detector thread - that seems like a great safety feature!

 

[blacksapphirez]

@swatski you are my hero. I'm going to follow your mod

https://jetboaters.net/threads/who-...roup-buy-on-impellers.5568/page-2#post-130834

 

[njmr2fan]

so I got brave and tore up my engine... na it wasn't that bad. just removal of the air filter and throttle body. I saw the AR190 write up and thought i have to remove the entire intake manifold but na our's is bit easier. 13mm and a hex bit

that flame arrestor is in there very tight...had to fight a good bit to get it out without damaging the aluminum intake manifold... but gained 2mph and 200~250rpm. Very quick BUT...cavitates out of the hole. may need higher pitched impellers ...

So what is the easiest, safest way to remove the ribbon? Any special tool?

 

[swatski]

By far one of the most useful tips. Once you get the throttle body off, take a screwdriver and long screw and screw it into the center of the ribbon. Then use a claw hammer to gently extract the ribbon in one piece. Works the same in all 1.8l N/A:

Only thing I don't love about the idea of putting a screw into it, kind of ruins it and will definitely show that it was tampered. If you worry about that, it will come out relatively easy with just a flat head screwdriver to wedge it out:

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[robert843]

@swatski do you think your boat was over revving because the wear ring was worn? looks like same mph at 150~rpm more.

@Big Shasta I don't think its necessary... blower will take out any fumes and stock filter will be another barrier...not that it will stop it. but after the engine is on, its sucking in air ... so i would turn on the blower only when i am starting just like i would on any boat

This is interesting I have seen this several times now. Most of the 240 guys tell me there boat spins at about 7500 rpms but for some reason mine spins at 7850 rpm as well not sure what the difference is that would cause this.

 

[ar240owner]

I'm wondering how a 240 would do !!! Thinking about trying !!

 

[swatski]

@robert843 Assuming you have no major cavitation, and are not under-propped, when hitting your max RPM, you should be very happy!!! - seems you are hitting the hard limiter. Which indicates your engine is generating all the power.

Here is the rev limiter table for 1.8l N/A:



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[robert843]

I'm wondering how a 240 would do !!! Thinking about trying !!

What are your max rpm's now

 

[robert843]

@robert843 Assuming you have no major cavitation, and are not under-propped, when hitting your max RPM, you should be very happy!!! - seems you are hitting the hard limiter. Which indicates your engine is generating all the power.

Here is the rev limiter table for 1.8l N/A:

View attachment 33939

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I'm now wondering if someone didn't already do a ribbon delete on my boat since I'm already turning that fast. No cavitation but no real mph gain it looks like compared to the other 240's as its still a low 50's top speed

 

[ar240owner]

7660

 

[swatski]

@robert843 It's time to scrape all those nasty barnacles off of your hull good sir! LOL. (I'm joking, of course!)
Low 50s is great, there are many 240s that will not do it.

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[swatski]

I'm now wondering if someone didn't already do a ribbon delete on my boat since I'm already turning that fast. No cavitation but no real mph gain it looks like compared to the other 240's as its still a low 50's top speed

It could be. If you are running OEM impellers in pristine shape. Any significant damage and all bets are off, but I don't think you would be running over 50 with significantly damaged impellers.
I think these boats hit a real speed wall, bestowed by the hull design.

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