Totally fustrated, dead cylinder plus will not idle.

[Grumpy]

 I am building a replacement bike to replace the Interstate I totaled, I took the complete engine, carbs etc from the is and put it in the standard I am building. Engine ran perfect even after the accident, no miss, smooth as glass. I started it today in the standard, # 3 cylinder will not fire at idle. In fact the bike will not run at all unless the choke in on. Revved up the bike fires on all 6. Checked compression, all cyls 95 to 100 lbs. Good hot spark to all cyls. acts like low speed jets, but opening each one a turn does not make any difference in how it runs. I checked the gas in the bowls, draining each at a time, amount of gas drained is the same for each carb. Really getting fustrated and running out of ideas. Really hate pulling the carbs , but looks like that is next. Any ideas on some thing I may have missed ?

[Pappy!]

Grumpy - time to go into the carbs my friend! Opening the needles a turn will do nothing if the jet itself is gummed up.

[IamGCW]

Sounds like the issue Eddie is having.  Maybe try the trick John suggests, pull a heavy vacuum on the drain and then open it.  It may dislodge the particle(s).  It does look like you will be pulling the carbs though.

Missed you today at the Cove. 

Gil 

[Michvalk]

Did you try closing the jet down to lightly seated, then open it back up? Sometimes that will poke the crud just enough to get things moving. Then you can add carb cleaner

[Grumpy]

Did you try closing the jet down to lightly seated, then open it back up? Sometimes that will poke the crud just enough to get things moving. Then you can add carb cleaner

Yep tried that, no luck.

[Thunderbolt]

Been sitting while you have been mending Bill.  I vote for taking the carbs back out and cleaning the slow jets.  Been too much of that lately.  My Interstate has sat too much lately too.  It didn't run like it should either. 

[3W-lonerider]

you don't need to pull the carbs to replace the low speed jets.
iv'e takin the intakes off already and got the carb bowls off and have replaced the low speed jets that way.
i have big hands so someone with smaller hands would'nt have much of an issue.
i use one of those little rachating bit holders to do mine.
on the one bike i done i replaced all six low speed jets in less than 2 hours.

[Grumpy]

you don't need to pull the carbs to replace the low speed jets.
iv'e takin the intakes off already and got the carb bowls off and have replaced the low speed jets that way.
i have big hands so someone with smaller hands would'nt have much of an issue.
i use one of those little rachating bit holders to do mine.
on the one bike i done i replaced all six low speed jets in less than 2 hours.

I will have to pull them, still have 3 fingers that don't bend on the right hand, and the steel pins in the left restrict movement, I pulled the slow jet needle on the problem carb and blew it out with air, took me an hour to do that. Guess I gotta pull them.  Really has me wondering, before I put the carbs on, I pulled the bowls and the low speed jets, they were clear, could see through them.

[98valk]

bad diaphragm vacuum petcock?
blocked tank vent hose?
tank fuel filter screen clogged?

[Thunderbolt]

Bill the tank or lines could have clogged them up again.  I usually run some fresh gas through the lines with the drains open before I try to fire it up after cleaning everything up.  Otherwise when you first fire it up the jet will suck it up on the first gulp.  As you know 35 or 38 thousandths is barely visible holding it up to the light.

[R J]

Bill, old age memory has just blown me out of the water, so bare with me.

That hot carb cleaner, like SeaFoam.   Get a can, pour it all in the fuel tank.

Regardless as to how bad it is running, take it for a ride, and try to get a good snot full into the carbs.

Let it set overnight, in as upright of a position as possible.    Give the concoction at least 12 hours to work.

Fire the old girl up and go for a 25 mile at least ride, under 2,000 RPM's, at your turn around place and as you head for home, twist that right arm as tight as you can get it in 2nd or 3rd gear.     Give her a full throttle jab shift to the next gear up.   That should empty the gas out of the carbs.   OOps, forgot to tell ya to turn the petcock off when ya turn around.     Want to try and empty the carbs.   As it starts to stumble, turn the gas on and stab her in the butt again.    Hold it for about 5 seconds.    Untwist the right arm and run her back home under 2,000 rpm's.

When ya get home, put another full can of treatment in the gas tank.   Make sure it gets into the carbs before ya shut it off.   Again, stand it up on the stand as straight as possible.   Let her set for another 12 hours minimum.    Start her and let idle for a few seconds.   Drive off keeping under 2,000 rpm's for about 5 or 6 miles.    Bring her up to normal running speed in town or where ever you are.

Ya got any stumble, rough idle and or etc?

Try the 12 hour treatment one more time.   If this doesn't cure the problem, plan on doing a CARB removal and through cleaning.

Good luck brother.

Peace.
RJ.

[Grumpy]

Well made up my mind to pull them, going to dump them in the carb cleaner. I ordered a set of 38 slow jets a few min. ago. Really ticks me off, that it ran great when I pulled it from the IS, not will not run unless choked, and stumbles and sputters bad. Dang, thought I was almost done with it.

[Tropic traveler]

Eerily similar symptoms to the problem I'm having with my '97.
Sat too long due to a tank cleaning & procrastination. Pulled the carbs & gave them a thorough cleaning & added new 38 slows. The carbs were not that dirty. Another round of procrastination after I reinstalled the carbs & filled the bowls to check for leaks. Bike will NOT idle unless choke is fully engaged and has a near constant popping & backfiring at all speeds except WOT. Without the choke it shuts off at anything under 1500 rpm like you hit the kill button.
Tried heavy doses of carb cleaner, riding with the gas cap open & attempted to isolate a bad cylinder that seems to be moving around. No dice.  
Is this alky gas that bad or did I do something wrong?  ???  

[Flint]

I feel for ya grumpy, started cleaning mine today not a fun job.

[Grumpy]

Found some thing strange #3 carb was the one giving me fits, tore it down and found the slow jet needle was missing the metal washer, there is supposed to be a spring, metal washer and o-ring, just the washer was not there ? wondering it that was causing the problem.

[Thunderbolt]

Bill I have found that on the pilot jet that you are describing sometimes the o-ring or a washer will stick in there and I use a small piece of wire with a small hook bent onto the end to dislodge and pull the lost pieces out.  If you happen to drop one of the little suckers it is almost impossible to find.

[pancho]

Well made up my mind to pull them, going to dump them in the carb cleaner. I ordered a set of 38 slow jets a few min. ago. Really ticks me off, that it ran great when I pulled it from the IS, not will not run unless choked, and stumbles and sputters bad. Dang, thought I was almost done with it.

When you get it finished, and the first time you take it down the road running perfectly, you will think,          "it was all worth it!!"

[Ricky-D]

Got so many hijackers on this thread that Grumpy's post's are lost in the shuffle.

***

[Bagger John - #3785]

"Ran perfectly when you took it off the I/S"...

Did you bring the carbs over too, or just the motor?

How about the vacuum lines and caps - got a crack in one, perhaps?

[Grumpy]

"Ran perfectly when you took it off the I/S"...

Did you bring the carbs over too, or just the motor?

How about the vacuum lines and caps - got a crack in one, perhaps?

Carbs off the IS also, replaced all hoses and vacuum caps, even new 0-rings on the intake tubes.