misfiring

[pisten-bully]

I may have found my "AHA!" moment here, thanks to Tom. Yesterday I changed out the modern paper sediment bowl filter back to the old, original style element but I never tested fuel flow beyond that point:



This morning I removed the carburetor again and reconnected the bowl to the fuel line and opened up the petcock.... I stopped counting when I got to 60 seconds and the bowl wasn't even half full!



I don't know the spec for fuel flow, but that seems waaay too long to fill the bowl. Now I've got something to fix! Thanks Tom!

[pisten-bully]

Dang! False alarm....sheesh. I had 40 miles since my last fill, there shoulda been a gallon left but the main tank is empty. Running the reserve through and there’s good flow into the bowl....feel like an idiot. Removing the carb and sediment filter three times and losing all that gas, plus lots of idle time shouldn’t account for a gallon. Back to the list I guess.

[exeric]

This has been a very interesting thread for me, as I'm not a good mechanic, or diagnostician. I feel bad for what you're going through, Harry but I'm learning a lot. I know you'll get there.

[ChiefTwoKicks]

Thanks for the response to my suggestion, Harry. I said that, not to be critical of your knowledge or approach to finding your gremlin. However, as you can see, with this example, there may be more than one gremlin, maybe several. With the check list, you will be able to pick-'em off one at a time, you'll discover how much actual maintenance these old bikes really need.

I sort of like to compare these old bikes,and what you have to do to keep them to keep them performing optimally... like owning an mid-sixties VW Bug... cheap to operate, fun to drive, fairly reliable, air cooled (thats your first clue,here) and most importantly they always need a little tweaking every 1000 miles or so (valve adjustments,or at least checking them),etc. Those old VW's are famous for checking the valve lash at proper intervals, or you can end up with tons of heart ache, for lack of ROUTINE maintenance.... moving on...

Here's where I'm going to beat on you a bit... man, that original gas filter looks REALLY filthy !! I don't know what your gasoline additives are up there in the northeast, we don't have much of an issue out here in California. But it appears that your fuel may be of major concern for contaminants. Cotton often speak about this. While you're at it, you might want to pull your tanks, and rinse them out real good. All that crap that gets past the filter element goes right through the needle and seat, maybe restricting the flow to the bowl. If that junk sticks to the filter element, it likely sticks to everything else on the way to the combustion chamber, and out the exhaust pipe. Obviously, you can't get rid of it all, but you can clean most of the sludge (non-burning fuel additives),before it gets too bad. Even pulling the heads, and scraping off the carbon deposits.

You're certainly making progress, and again, one by one, you eventually will conquer these issues. Just remember, don't lose hope. Soldier on, slow and steady. Stay with the check list, you may be adding even more to it, too !! Patience, is you best ally.

I'm thinking, (that may get me in trouble here...) you guys back east, generally have a much shorter riding season than we do here on the west coast (at least, west of the Mississippi). In many cases your bikes sit, unridden for long periods of time. When the weather breaks, or you have a few hours of free time, you roll out the bike and take it for a spin. (I'm embellishing here to make a point). OK, your bikes really likes to be ridden. And when you ride them often, you naturally pay more attention to the maintenance intervals. When they sit, often times the maintenance intervals get moved back to the end of the list. Not blaming anyone, its a natural thing to just go out to the barn, jump on the bike, go for a spin and tell yourself you'll do the maintenance later. Doesn't always end up that way, things come up and the "I'll do it later" card is now on the table !! I'm guilty too ! Probably way more guilty than many others.
I ride almost everyday, so my spectrum is at the other end of the scale, but I think you get my point. I've been caught in this trap many times,too. I'm getting better... and my bike thanks me for it.

I apologize for my long, essay-like musings here. Its my nature to be quite descriptive in communication skills. I wanted to be a professional story-teller at one point in my life, but thats no excuse. It's a few of my thoughts, meant hopefully to encourage you in your quest for Victory. I know you'll win this battle and get your bike fixed before too long.

C2K

[pisten-bully]

its a natural thing to just go out to the barn, jump on the bike, go for a spin and tell yourself you'll do the maintenance later. Doesn't always end up that way, things come up and the "I'll do it later" card is now on the table !! I'm guilty too ! Probably way more guilty than many others.

Guilty as charged! And there's also times I've intended to go for a ride and then spent time with maintenance instead, so I'm not all bad!

Setting this aside until parts show up. New float to eliminate the possibility that my swollen float is hanging up and stopping fuel flow.... I didn't observe that but once the carburetor is all together you can't see what's happening in there. And new bushings for the distributor, there's some movement there so best to get rid of it.

[T. Cotten]

... New float to eliminate the possibility that my swollen float is hanging up and stopping fuel flow.... I didn't observe that but once the carburetor is all together you can't see what's happening in there...

Just turn the carb upside down, Harry!

And suck on the valve. Even a perfect float can rub or hang up on the bowlstem if its not in the "sweet spot", especially if there is slop on the pivot.

Did you by any chance put a caliper on it? If it came out of the bowl easily, it ain't a "bloat",.. yet...

....Cotten

[tfburke3]

Guilty as charged! And there's also times I've intended to go for a ride and then spent time with maintenance instead, so I'm not all bad!

Setting this aside until parts show up. New float to eliminate the possibility that my swollen float is hanging up and stopping fuel flow.... I didn't observe that but once the carburetor is all together you can't see what's happening in there. And new bushings for the distributor, there's some movement there so best to get rid of it.

If you covered the bowl stem hole and observed the fill rate and level,then uncover to drain and the float drops to the bottom I doubt a hung up float is the problem.When the float hangs up,usually when you first try to get the bowl oriented right,the problem is fuel overflow.If you hung up closed on assembly which would practically be impossible it wouldnt fire at all unless it was moving from closed to slightluy open,back to close,but seems unlikely.
I would also pull the nozzle and blow out the idle passage while you got it apart,especially after seeing your filter.
Lookin forward to your success.
Tom

[T. Cotten]

If you covered the bowl stem hole and observed the fill rate and level,then uncover to drain and the float drops to the bottom I doubt a hung up float is the problem...

You are leaving out the bowlstem variable, Tom!

Just the indexing of the bowl upon the body can make a difference.
(The valve is supposed to be 'under the power needle', but WLA folks pull their hair out because the linkages require the bowl to be ninety degrees to the body.)

The only way I know to be certain the float is in the sweet spot is to put the bowl on the body indexed, flip it over, and suck.
(OHVs can drive you nuts, too.)

....Cotten
PS: I often relieved side-bowl models for a wider arc of indexing clearance.

[pisten-bully]

Thanks Cotten and Tom, seems like a while ago (when it really was only a week or two) when I first had the bowl off, I couldn’t get the float out of the bowl without squeezing it gently to clear the rim, and I don’t recall it ever going in tight like that....that’s why I’ve got a fresh one coming. The other day, and before too, with the bowl off the carb and connected to the fuel supply, it all worked correctly. Float rose with the fuel and shut off the flow, and with the bowl upside down I’ve gently blown into the bowl feed/needle seat and not been able to get any air past.

Carb’s on the bench, and even though I ran a pipe cleaner soaked in acetone up through the nozzle, it’d be a wise move to take out the plugs and clean the idle passage too!

[T. Cotten]

...that’s why I’ve got a fresh one coming...

What will keep that one from swelling, Harry?

(Was it one of my early productions?)

Blowing on the valve doesn't tell you anything; Suction does.

Please completely remove the nozzle and venturi for inspection, as crud can collect in the annular void around it.

....Cotten

[pisten-bully]

What will keep that one from swelling, Harry?

(Was it one of my early productions?)

Blowing on the valve doesn't tell you anything; Suction does.

Please completely remove the nozzle and venturi for inspection, as crud can collect in the annular void around it.

....Cotten

Cotten, This float is 2.475 and it only comes out if it’s squeezed, it’s 10 years old from Greer’s (not Rubber Ducky), I’d expect a new one to be more stable and not swell for a while. And I sucked on the valve and it’s not letting any air past, now I’m soaking the nozzle in Kroil because it won’t push out with my finger!

[T. Cotten]

Cotten, This float is 2.475 and it only comes out if it’s squeezed, it’s 10 years old from Greer’s (not Rubber Ducky), I’d expect a new one to be more stable and not swell for a while...

Sure, Harry!

A while anyway...

....Cotten
PS: The easiest way to pull *most* nozzles is a brake cable with the end turned down less than 3/16"

[pisten-bully]

PS: The easiest way to pull *most* nozzles is a brake cable with the end turned down less than 3/16"

Brilliant! Thanks Cotten,

[T. Cotten]

Brilliant! Thanks Cotten,

It wasn't my original idea, Harry!

Check out back-packer's gun cleaning kits.

....Cotten

[pisten-bully]

Parts are taking a while to get these days, but I received a new float on Saturday, Rubber Ducky from Greer’s, and installed it. I had previously removed all the plugs and the nozzle, passed a pipe cleaner soaked in acetone through them all then blew them out, then all back together with the new float. Sunday I took it on a 15 mile ride, close to home, and it ran well after dialing the carb back in. This morning I ventured a little further and got in a 65 mile ride, again with zero misfires...bike ran very well.

I keep remembering the recent incident where I got 90 miles out and it started misfiring and I couldn’t make it home....so I still don’t trust it fully or trust the idea that the float was the problem all along. But someone said most electrical problems are fuel related, and most fuel related problems are electrical.

More miles after this weather blows through!

Oh, and I also received and installed the Thor Cap capacitor that Jason showed us!