GTS cavitation?

[MAL]

Been doing this for over 30 years so take it for what it is worth.

I have seen countless engines seized from the crap clear fuel line. Yes, when new you can see air leaks. As it ages and gets hard it always develops air leaks or it breaks off from the engine vibrations. But nobody checks for leaks after they install it so when it gets hard in a year and starts pulling air up under the dash on the fuel selector where you can't see it then on a WOT run across the lake your engine seizes.

The black fuel line doesn't get hard and makes a better seal on all the fittings, it just doesn't leak if you install it correctly with good quality zipties. You can also use your pop-off tester to put a few psi into the fuel system and see if the pressure drops to check for leaks so you can verify your fuel selector and fuel strainer are not bad along with your connections.

Bottom line all the clear hose will get brittle, hard and eventually leak. You could use genuine Tygon hose but you are just as good off with standard black automotive line. If you want the best of the best then use Motion Pro Premium Fuel Hose. It is what Yamaha uses on their watercraft and I have some that is 35 years old and still soft and pliable.

I watch my fuel lines on every cold start. It helps me learn about fuel air mixture and its affects on how the engine is running. You can see why an engine stumbles as it warms up. Black lines are not perfect either. Traditional black fuel line does get hard. I have had a black fuel line leak. I left the black supply line between carbs, and the only reason I caught the leak was because I pressure tested two carbs at the same time that were connected together. I I won't argue about the quality of Yamahas fuel line because I can see it is very good, but it doesn't help find a leak in the pickup, selector, damaged barb, O-ring or the hose itself. Those leaks will seize an engine also. You don't have to look under the dash to see if air is getting into the carb...just look at the line to the carb.

The bottom line is that if you have black lines you should have the system pressure tested as a regular maintenance item. If you have clear lines watch the line going to the carb regularly. Pick your poison

 

[burtshaver2021]

I watch my fuel lines on every cold start. It helps me learn about fuel air mixture and its affects on how the engine is running. You can see why an engine stumbles as it warms up. Black lines are not perfect either. Traditional black fuel line does get hard. I have had a black fuel line leak. I left the black supply line between carbs, and the only reason I caught the leak was because I pressure tested two carbs at the same time that were connected together. I I won't argue about the quality of Yamahas fuel line because I can see it is very good, but it doesn't help find a leak in the pickup, selector, damaged barb, O-ring or the hose itself. Those leaks will seize an engine also. You don't have to look under the dash to see if air is getting into the carb...just look at the line to the carb.

The bottom line is that if you have black lines you should have the system pressure tested as a regular maintenance item. If you have clear lines watch the line going to the carb regularly. Pick your poison

I’m not going to argue either however black automotive fuel lines can last damn best forever, 20 years anyways. You don’t have to pressure test fuel system as a maintenance item, just do it when your getting her ready if your worried about it and good to go. If you ever have an issue, bogging or running away then it’s time for o stop driving and figure out what’s wrong. I’ve never had to worry about them after they are done. But I’m definitely not here to argue with you or tell you, you are wrong. I just recommend the black lines when someone is having issues with air leaks or asks because I think it’s the best route. Seen to many threads with issues with the clear and I would hate to have replace them every year due to getting hard and brittle. But again , if it works for anyone, by all means do what works

 

[MAL]

I’m not going to argue either however black automotive fuel lines can last damn best forever, 20 years anyways. You don’t have to pressure test fuel system as a maintenance item, just do it when your getting her ready if your worried about it and good to go. If you ever have an issue, bogging or running away then it’s time for o stop driving and figure out what’s wrong. I’ve never had to worry about them after they are done. But I’m definitely not here to argue with you or tell you, you are wrong. I just recommend the black lines when someone is having issues with air leaks or asks because I think it’s the best route. Seen to many threads with issues with the clear and I would hate to have replace them every year due to getting hard and brittle. But again , if it works for anyone, by all means do what works

With clear lines I don't have to wait until the ski is hungry for fuel to find and fix the problem...I just look at it. I am not sure exactly what you mean by black automotive fuel line. The black automotive fuel line that I am used to is kind of hard when it is new. It typically won't leak but I think I would want worm gear clamps on it. I have never had to replace any of the lines that I put on , but I am about to replace the black automotive line that I first installed because I cant see through it.

 

[burtshaver2021]

With clear lines I don't have to wait until the ski is hungry for fuel to find and fix the problem...I just look at it. I am not sure exactly what you mean by black automotive fuel line. The black automotive fuel line that I am used to is kind of hard when it is new. It typically won't leak but I think I would want worm gear clamps on it. I have never had to replace any of the lines that I put on , but I am about to replace the black automotive line that I first installed because I cant see through it.

Sounds good

 

[Gwstaudy]

I’ve got the black automotive fuel lines on the main line but my return line is the clear because I didn’t buy enough to change it. I noticed that when I pulled my filter/water separator the filter in it was sucked in around the center. I thought it was odd but didn’t think anything of it. Now thinking about it it would make sense why it was running good because the filter was fine. When the filter started squeezing together it can’t suck as much gas through. Does this sound possible?

 

[MAL]

I’ve got the black automotive fuel lines on the main line but my return line is the clear because I didn’t buy enough to change it. I noticed that when I pulled my filter/water separator the filter in it was sucked in around the center. I thought it was odd but didn’t think anything of it. Now thinking about it it would make sense why it was running good because the filter was fine. When the filter started squeezing together it can’t suck as much gas through. Does this sound possible?

If the filter in the water separator is plugged it will cause a lean condition. The filter can get crushed if it is not properly installed. Sometimes it can fall of while trying to screw the bowl on to the housing and then gets crushed as it gets tightened.

 

[Gwstaudy]

If the filter in the water separator is plugged it will cause a lean condition. The filter can get crushed if it is not properly installed. Sometimes it can fall of while trying to screw the bowl on to the housing and then gets crushed as it gets tightened.

I don’t know if it got crushed. I was thinking it was crappy quality and as it had suction on it it got squeezed together and restricted fuel flow. They are cheap but I had a couple on hand so I went ahead and replaced it and the o ring.

 

[mikidymac]

I don’t know if it got crushed. I was thinking it was crappy quality and as it had suction on it it got squeezed together and restricted fuel flow. They are cheap but I had a couple on hand so I went ahead and replaced it and the o ring.

I have seen them get like that as @MAL indicated when they are not pushed up far enough and the bowl compresses them. Also they are no the same quality as OEM and the OEM have pretty much been discontinued.

These carbs really don't have enough suction force to collapse them.