F 115 fuel system issue

[DennisG01]

Gas look clean. I have a picture, but I’m trying to figure out how to make the files smaller so it’ll upload.

Gotcha. No worries. If it looked clear, smelled like gas and there wasn't any separation after an hour, then the gas, itself, shouldn't be the issue.

[captron904]

Gas look clean. I have a picture, but I’m trying to figure out how to make the files smaller so it’ll upload.

[DennisG01]

What did the fuel look like when you drained the VST? Did you let it set for a while like we talked about previously?

Gas with ethanol in it should not cause a problem if it's fresh/clean and, especially, if you're religious about using a good additive like Startron.

BUT... since you didn't have the issue today, I don't think you're having a "supply" problem like I initially thinking.

[captron904]

Put the boat in the water this morning. Had my mechanic check the fuel pressures which are good. The fuel cooler is working as it should. The VST is good. Today the weather was cooler so I didn’t experience the vapor lock that I do when it’s hot outside. part of me is starting to question the integrity of the gas that I’m getting? I use ethanol free, but I’ve had the same problem a couple years ago, which I think was some bad gas. I get the gas at the same location every day. I know if I use regular gas with ethanol this motor really acts up. I replaced the fuel/water separator last week and the gas looked good tho. Next step is to hook up the remote tank and see how that goes.

[DennisG01]

Oh... hopefully this was obvious, but in post #21 I meant to type "I wasn't as clear".

[captron904]

Thanks guy's. Got my Yamaha mechanic scheduled for tomorrow. I'll post the results

[DennisG01]

I realized I was as clear as I should have been with my response in #12. Yes, it's two totally different systems... but both systems "could" be the issue.

The level of fuel inside the VST is a possibility (although, truthfully, I don't "think" that will siphon drain). But it would be good to verify that it is, indeed, remaining full of fuel. And it's also an easy way to check fuel quality.

Then there's the cooling issue which, of course, is the water flow. As noted above, though, follow (backwards) the pee hose and see where it goes and/or where it T's off.

[ausnoelm]

Don't fall into the old "I read" I was told" "I think" you have to KNOW something is good or you're just stabbing in the dark.

[captron904]

Thanks! I'll check the cooler.

[99yam40]

I was told that if the motor is peeing, then the cooler is getting flow. Bulb not going flat, just soft.

I know very little about your motor, but I have read some fuel coolers can show a tell tail but not have poper flow thru the fuel cooler.
just saying it is something to check on.
taking some tubing off to verify should not be that difficult

[captron904]

Got it, Thanks! Unfortunately I use the boat everyday and combined with my mechanics schedule, I'm unable to get it in the shop right away.

[DennisG01]

I was told that if the motor is peeing, then the cooler is getting flow. Bulb not going flat, just soft.

You're referring to two totally different systems. "Peeing" is about water flow. When we're referencing the VST (fuel cooler), we're talking about... well... fuel

Please don't take this the wrong way as there is no malice intended... but if this stuff isn't in your wheelhouse, you might be best served to get a pro to look at it. The last thing you want to do is save $5 only to spend $10 later.

[captron904]

I was told that if the motor is peeing, then the cooler is getting flow. Bulb not going flat, just soft.

[99yam40]

he said if he pumps the primer bulb before restating it does not stall.
also it is very hard to pump a ball that is flat.

apparently, he has not even checked to make sure the fuel cooler is getting flow either.

[ausnoelm]

If the primer bulb is in fact going flat, then your very first test (as mentioned) is another tank, complete with fuel line and primer, the bulb going flat is a restriction between the primer and the tank air vent! That said, can you confirm the bulb is going flat, not just "soft"