Bad Jet Block Gasket?

[fishslayeryo]

Howdy all!
My bike sat for awhile and fuel line to carb busted and dumped 26years of slug into my petcock, which clogged it up. Prefilters long gone, however I have a moose racing inline filter, so nothing nasty getting into the crab.

I pulled the tank and cleaned it and also the petcock. It was gummed up pretty good but got it all cleaned up with new rubber. After I put it back together bike still ran funny. She ran super rich to where she was bogging and stumbling. I did notice after I would turn off the petcock and some fuel would get consumed, it would run better. I also noticed with the petcock on, no mater what I did to the idle screw it did NOT effect the idle...would be very low and I had to hold the throttle turned a tad to keep it from stalling. Once I closed the petcock and some fuel would get consumed, then the idle screw position would effect the idle.

My initial thoughts were that the carb needed a cleaning and the float bowl was stuck open. So I pulled it apart cleaned it(not dipping) thoroughly and just put it back together. With it warmed up, new plug, clean filter, fresh fuel and cleaned carb it is still doing that same thing.

This is a RB Carb from previous owner. I did see an old jet block gasket had been replaced as I have the old one in with some spare jets. Is the jet block gasket bad again? Would this cause these symptoms? I did check the float bowl height and it was within spec. I have the same jets in that ran fine prior.

Thanks in advance for any insight!

[bufftester]

I would take a good look (and probably replace) the float needle and verify that it's seating and sealing. Reset the carb height to 18mm after thoroughly cleaning it, again. If that doesn't fix it then try a new jet block gasket.

[fishslayeryo]

I would take a good look (and probably replace) the float needle and verify that it's seating and sealing. Reset the carb height to 18mm after thoroughly cleaning it, again. If that doesn't fix it then try a new jet block gasket.

Thanks for the reply! I did confirm it was seating and sealing. Used some spare fuel line and blew thru it till it engaged and it let no air out once it did. The tip was perfect as well. Just ordered the all balls jet block gasket kit. Who knows maybe the prior owner has a cheap ebay gasket kit in there. I bought some fuel line for ebay busted in 1year. Hopefully this fixes it.

FYI part number for PWK carb from all balls is 26-10011

Cheers!
Yo Han

[John_S]

That’s good to know that they make one and it’s on Amazon. I bought one from Jets R Us that only lasted two years. One day it was running fine the next it was running like yours. That was 17.00 plus the 8.00 shipping.

[John_S]

This is a great way to see if it needs to be replaced. I do this after installing a new one so I know it’s right.

[SS109]

There's four things I now do on any PWK carb if it's been sitting too long... full cleaning, replace jet block gasket, polish needle seat, and replace the pilot and main jets.

[fishslayeryo]

Thanks for the response fellas!

SS109, yessir i have no clue how long the current gaskets have been in there also if they were decent quality, so happy about the all balls coming in.

John_S saw the Jets R Us one as well and didn't know if they were decent quality, hopefully all balls last longer than 2 years and thanks for the video! Will do that test to see for sure!

I just got back from harbor freight as this was a great excuse to finally get a vacuum pump. Got a cheapo for 25 bucks which I will love when i need to do brake fluids next! Saw this video for checking proper seal on float needle what drove me to get me a vacuum pump:)