Miss when cruising

[315TDSidewinder]

Does it have a fuel return to tank fuel pump basket? Reason I ask is, fp should be lower with engine running compared to engine not running. You're saying fp is higher when engine is running. That's not normal. Either there's a problem with regulator itself, you might have a return line restriction. Way back in like 2018, the plastic return elbow fitting (front left corner of fuel tank) was changed to have larger opening, or some just drilled it bigger. It was restricting return flow. This was especially noticed when installing a larger fuel pump.
Unless there's something we don't know about the tune, the fp should be 43-44 lbs key on engine not running. This should be checked during the 2-3 second fuel pump run when key is first turned on.

It returns to the top of the tank but looking at it and idk if he has it hooked up right. It looks like he has it going to the check valve next to the red 90* fitting. Is that the fuel return and the dude hooked it up wrong

 

[sxr70001]

The red fitting is the fuel return that we drill out. Red is old style.

 

[315TDSidewinder]

The red fitting is the fuel return that we drill out. Red is old style.

Dude has the fuel return hooked to where the vent goes then. Coming off the the regulator he ran that to the check valve and ran the vent for the check valve to the return. Should have notice it yesterday.

 

[KnappAttack]

This is a good place to start. Nearly everyone is doing this to keep the banana surge tank full and keep from running out of fuel as well. I'm using steel elbows into the tank return on top of the fuel pickup with large fuel return line. Be careful drilling into the top of the plastic plate.

Post in thread '3 gallons or less in your tank!!'

Dec 11, 2021

Got mine done today. Ended up not using the SAE J30R7 hose and buying some SAE J30R9 hose. The 30R9 hose has a thermoplastic liner (or something like that) so it won't harden with the ethanol in fuel. That hose was much harder to put on the fuel pressure regulator but I got it on by heating up the end of the hose and spraying a little WD-40 in the end.

• twyztid

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Fuel Elbow 5/16" Line 90 Degree Gas Tank Fitting Metal with Rubber Grommet | eBay

90 Degree Fuel Tank Fitting. 5/16" x 1/4" fuel line connection. Lawn & Garden. Personal Watercraft (PWC).

www.ebay.com

 

[Turboflash]

Dude has the fuel return hooked to where the vent goes then. Coming off the the regulator he ran that to the check valve and ran the vent for the check valve to the return. Should have notice it yesterday.

That's wrong. Glad you figured it out. That's why your fp was messed up!

 

[315TDSidewinder]

That's wrong. Glad you figured it out. That's why your fp was messed up!

I still have a new 3bar coming just going to swap that out as well thanks for the help again guys

 

[fatchance]

I still have a new 3bar coming just going to swap that out as well thanks for the help again guys

Just test it before you throw the new 3bar in.
Won't hurt. Keep the new map sensor on the shelve for when you ultimately need it! Lol

 

[315TDSidewinder]

So I was able to get everything back in its place. Drilled out the red fitting for now and tested the sled. Stumble is gone but feels lazy next check for boost leaks.

 

[Doc Harley]

So I was able to get everything back in its place. Drilled out the red fitting for now and tested the sled. Stumble is gone but feels lazy next check for boost leaks.

Boost leaks; there are a set of clamps behind throttle bodies that have limiter spacers to limit the clamps ability to squeeze tight, basically stoppers. We have found that the clamps limiter spacers needed to be removed and trimmed down to allow the clamp to crush tighter to prevent boost leaks at throttle bodies. A common issue where higher then stock boost levels are desired.
Perhaps someone can chime in to give you some better direction. It's something no one enjoys doing, but a necessary evil.

 

[Turboflash]

So I was able to get everything back in its place. Drilled out the red fitting for now and tested the sled. Stumble is gone but feels lazy next check for boost leaks.

Lazy can have lots of causes. Clutching, gearing, too rich, boost leaks. Did you get a new MAP sensor to replace your old one?