Fuel selector valve - pros and cons of bypassing valve, race PWC venting

[K447]

... fuel ON/OFF switch ... It restricts the fuel from the tank to the carbs...

If the engine is not running lean at WOT, does the restriction matter?

In other words, if the selector On/Off valve is not causing a problem, what improvement does removing it provide?

[785 lugs]

If the engine is not running lean at WOT, does the restriction matter?

In other words, if the selector On/Off valve is not causing a problem, what improvement does removing it provide?

because they have a tendecy to go bad and it's not worth burning up a good motor over it ,on race ski's or just hi perf rec ski's they are not worth the trouble they can cause i don't run them on any of my ski's and also the tank vents go away also more problems then there worth also

[bowsniper]

Well theres an o-ring that can fail along with air seeping into the gas flow from bad sealing on the clamps. 1 less thing to go wrong. I dont think it would really restrict the flow so much..

---------- Post added at 04:32 PM ---------- Previous post was at 04:29 PM ----------

[QUOTE=skigolfnut;1689323] NICE carbs! I have the same ones.. Have you had trouble tuning them as the temperature changes? I heard they are hard to tune..Mine seem easy enough to tune.. I have good wash patterns.

1 More thing....Check your cam wheel for being tru and straight, my cable got hung up there because the cam wheel was bumped or dinged and the cam whweel was opened up a litttle and it would make the throttle stick and it wouldnt return correctly until i tapped on it.. that would be BAD if it stuck WOT! You might want to check it out to be sure.

I replaced mine with another one. Thank god for the parts bin!

[K447]

... 1 less thing to go wrong...

Actually removing the selector valve just changes what can go wrong.

Without a fuel valve, an unexpected pressure rise in the tank (from a stuck vent check valve) can force fuel into the non-running engine through the carbs. Liquid fuel in the engine can cause hydrolock damage, and excess fuel fumes from the flooded engine can fill the hull with explosive air+fuel mixture.

A well maintained or new fuel valve is easy enough to have. Not risking flooding the engine or blowing the ski up seems worthwhile.

[785 lugs]

Actually removing the selector valve just changes what can go wrong.

Without a fuel valve, an unexpected pressure rise in the tank (from a stuck vent check valve) can force fuel into the non-running engine through the carbs. Liquid fuel in the engine can cause hydrolock damage, and excess fuel fumes from the flooded engine can fill the hull with explosive air+fuel mixture.

A well maintained or new fuel valve is easy enough to have. Not risking flooding the engine or blowing the ski up seems worthwhile.

thats why i and most guys who race set them up with no restictors in the fuel vent line

[Derwood98]

Just curious, how did a thread questioning carb sync get on to fuel line restrictions??

[785 lugs]

Just curious, how did a thread questioning carb sync get on to fuel line restrictions??

because polarisracer seen a potential problem with his fuel switch hooked up and thats why and it is a very serious issue if you care about your motor you have to remember he is racing this ski not putzing around some lake somewhere holding it wide open as long as he does that switch can be a HUGE problem so Jeff was just trying to help and k447 wanted more info on the reason why you should remove it

[Derwood98]

Bob, I understand the reasoning, however, it was more of a general statement than anything. Why do we always get off topic so badly. I realize the relevance of being off topic, but for future explorers, it just makes these discussions very difficult to follow. Not saying what's being said is not important, just do so in another thread as to keep the information data base as on topic as it can.

I share this from my own personal frustration with this site as when searching a topic, I get bounced around from thread to threat to get the answer. (Hangs head.) Sorry, back on topic please.

[Derwood98]

Thank you!!!!

[K447]

Thank you!!!!

I think we all like to keep things organized, but it seems to be human nature to wander off-topic Happens to all of us from time to time.

Sometimes the most interesting info pops up from an off-topic comment or suggestion.