Not running consistently after Carb and Petcock Rebuild

[wwh]

A little background:

I used to ride 454's back in the 80's, loved them and decided recently to get a couple for my son and I to ride.

One I purchased that is giving me fits is a 1989 model and was in pretty good shape with 28K miles on it. It appeared to have been moderately maintained and it seemed to run fine when I test road it.

We trailered it back down to Texas from the up north and when I went to ride it again, it kept starving for fuel and stalling when climbing a hill at all, I was able to run it on choke and get it back home and decided to just pull everything apart figure out where the issue was.

The petcock had a bad seal and appeared to be the culprit as fuel was not flowing properly when the tank was off and I pulled a vacuum on the diaphragm, so I pulled it apart, put a new kit in it and it flowed fuel afterwards fine again.

But while I had the tank off, I went ahead and pulled the carbs, and fully rebuilt them. I am used to rebuilding carbs on my watercraft and had not on a bike in some time, but it went smoothly and everything seemed to go back into place pretty straightforward.

When I had pulled the old pilot screws, they were a bit off from one another, which I Know happens  (one was about 1.5 turns out and the other was almost 3 turns out)

Looking at one of the manuals I had, I set them both at 1.75 and figured I would warm it up and start from there and adjust appropriately.

After several spins of the starter, the bike came to life on choke and then after a bit, I was able to back off the choke and it idled.  The rev sounded okay, it did not bobble or lose power as I started to rev it, and I could not feel or hear anything weird, so after another few minutes of idling and revving it a little, I figured, I would run it to the end of my street in low gear and see how it performed.

I got about 200 yards away, stopped and turned around and sat for a minute listening to it and revved it lightly a few times and then it died and would not restart after several attempts on or off choke.

So, I pushed it back to the house and looked for fuel leaks and there was a very minute amount at the end of the clear drain hose, and the airboxes looked a bit wet like it may have been rich, but the thing that caught my eye was the pilot screw on the side with the petcock had a little fuel on it and was obviously leaking a bit.  I wiped it off and checked the one on the other side and it was dry and clean.  Waited a few minutes and went back and checked with a paper towel and that first one was wet again. 

Not excessive leaking or dripping, but definitely leaking.

Looking for some guidance on the best way to troubleshoot from this point forward as I am not sure if it is getting too much fuel, since it seemed to rev fine, but then just died all of the sudden after appearing to run fine.

I did check the pulse lines and they are pulling a vacuum.   It just bothers me that the pilot screw on that one side is leaking.  The original ones did not have o-rings in them and the new kit did and I am used to having O-rings, so I used the o rings as I would on any of my other carbs for the jets.

Any help you guys can provide would be greatly appreciated.

Thank you!

[knoizy]

I wonder if there's a float sticking or some crud still stuck in the carbs. Not to question your experience with carbs but just to say when I got my 454 there was no way a can of carb cleaner was up to the task of actually cleaning them. Vinegar boil, airline and thinners finally got them clean and there was crud hiding in nearly every hole including the jets. Did you replace the float needles and reset the float height?

As far as troubleshooting, a 200 yard run might be far enough to check the plugs for mixture symptoms if you repeat the process. The pilot circuit is only active at idle so how does she run under load at higher revs? Fuel in the airbox is a classic symptom of a stuck float and just to check you have the air intake fully assembled to factory as leaving any of the intake parts off will affect the mixture. Not sure how the fuel is getting past the o-rings, its a concern but shouldn't affect the running too much. A valve adjustment would be a good idea anyway and maybe perform a check for leaks around the rubber boots. Could be worth pulling the carbs again and checking them over, hook up a temporary fuel line while you investigate further and using a hairdryer to warm the carb boots will make removal/installation much easier! Good luck.