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Moses Ludel

Carburetor Damage Caused by Ethanol and Winterized Gasoline

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   I think we've narrowed down the Harley's "no-start" condition to stale gas. Apparently,today's Ethanol treated gas only has a shelf life of 3 weeks to a Month,and this tank's been full for a little over 2 months. I plugged a good spark plug into the rear cylinder plug wire and cranked it,and it sparks fine,so I doubt there's an ignition problem. It COULD still be a stuck float,but either way,the gas is the problem. I wonder if that "Stabil" gas treatment will refresh gas that's already past its code date.

   Speed

Speed...Yup, ethanol could be the culprit on the H-D, though two months would be short time for any damage...The needle could be stuck in its seat.  Light tapping with a screwdriver handle at the float bowl will usually loosen the float needle.

Quick story:  My vintage Honda XR350R dirt bike set for over a year with no Stabil in the tank and "winter" (likely MTBE additive) fuel in the tank.  The dual carburetors each had clogged, with the primary carb's pilot jet low enough to be submerged in the fuel bowl.  The engine would not idle nor would it respond to mixture adjustments.

I dropped the primary bowl with the carb in place and sprayed carburetor cleaner directly upward through the pilot jet.  The jet would not clear out.  I eventually removed both carburetors (not a simple task) and rebuilt them with $20 (apiece) overhaul gasket kits from Honda, rather pricey for nothing more than O-rings and neoprene gaskets.  The pilot jet on the primary carburetor was so impacted with encrusted ethanol fuel that it was impossible to clean out.  No amount of soaking in caustic carburetor cleaner would help, either...You cannot "drill" through plugged jets, the brass will yield and cause the hole to elongate, which increases fuel flow and modifies the fuel mixture.

A new pilot jet (Keihin) and thorough carburetor rebuild and staging later, I learned not to leave "modern" ethanol or winterized fuel in the carburetor bowls.  I run the engine to stall with the petcocks turned off and the bike upright.  

Stabil does work within reason, though fuel quickly loses its volatility when stored.  In my experience, three months is the maximum age for fuel performance, and that's already a loss in performance.  I like to run the bikes down low on fuel before storing, add Stabil or equivalent, then run out the fuel in the bowls.

Motorcycles and ATVs/UTVs, even Jeep 4x4s, often get stored for lengthy periods.  The additives in contemporary gasoline can raise havoc during long storage...

Moses

Edited by Moses Ludel

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I'll go smack the float bowl with a big screwdriver handle in the morning. Haven't put much effort into the bike;mostly trying to get "The Bermuda Triangle" (BroncWorth) to run right. Might be easier to make the Harley run though. (Would be harder to use in the coming mini-ice age though.)

Speed

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Speed...Tap lightly, don't "smack", carburetor float bowls and bodies are expensive and can ding...You're simple trying to dislodge a stuck needle in its seat.  Typically a Viton tip needle...If everything else is okay, the float should be hanging down in the bowl with a gap between its tang and the needle.  A light "tap, tap, tap" should encourage the needle to unstick.

You should see some very cold weather this week at Elko, so ride with lots of leather if you test the H-D, the chill factor will be overwhelming.  Enjoy a snowy Thanksgiving according to the weather reports.  BroncWorth needs to behave, winter is near!

Moses

Edited by Moses Ludel

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   That's the problem-I'm trying to get the BroncWorth sorted before I have to work on it in the snow. I'm being told it has to be either the float's stuck or the power valve is bad. I'm also being told the power valve can be ruined by this Ethanol gas if it's soaked in it and not used for a long time. NAPA can get me a power valve for ten bucks,so that's next on the BroncWorth,and I'll look VERY closely at the float and needle-n-seat. On the bike though,not sure when I'll work on it. THIS makes me miss my house in Kittridge Canyon;The back door was wide enough to ride my bike into the living room to work on it,and there were no steps to negotiate! THIS house-not so lucky. What do you think of converting to an S&S Super E carb? I'm concerned it'll kill any semblance of gas mileage,but Dutch says he ran one on his 74 inch Shovel and got around 50 mpg on the highway. They cost a pretty good hunka change new,but I have a Bro here that has a used one he'll hook me up with for cheap and a favor down the road. I never liked S&S carbs because they had no accelerator pump and no choke,but the E has an accelerator pump,and I KNOW I've seen a choke assembly that fits between the air filter and the carb,but I can't find anyone that sells one.(Maybe it was a one-off? If that's the case,it'd be worth building one,or a few...)

Speed

   Speed

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Speed...I'm a strong advocate of factory engineering despite the inevitable foibles.  The motorcycle carburetor issues at northern Nevada include altitude compensation, and I'm not clear whether S&S has matter of fact jetting recommendations for these altitudes.  

It's enough to jet and maintain a stock carburetor.  Aftermarket carburetor targets and benchmarks often include expected camshaft changes and exhaust mods.  If your H-D is stock, I'd take a "restorative" approach with the original carburetor, save your money, and not get creative.  It's enough to juggle BroncWorth's carburetor issues!

Moses

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" It's enough to juggle BroncWorth's carburetor issues!"

That's true. The S&S is the Holley carb of the Harley world. They're VERY tuneable and can be made to work well with almost any V-twin engine. One of the benefits of the S&S is the adjustable main jet. Altitude can be easily adjusted for-IIRC it's something like a quarter turn per 1,000 feet. One of the downfalls of the S&S is ALSO the adjustable main jet-I've seen riders lean the carb out going down the road,trying to get good enough mileage to make the next town and melt the engine down. The old timers with those carbs,though,routinely tune as they ride to get the best possible mileage while keeping the engine happy.(especially the knucks and flatties which had a spark advance/retard adjustment in the left grip,mainly for easier starting,but I know a lot of guys would use it to dial up just a couple degrees of advance to get past that truck quicker,then back it off again to go easier on the motor.)

   I got a new power valve for the BroncWorth carb,pulled the carb off,fixed a leak through the carb into the air filter,checked the float,all appears fine,replaced the power valve,the battery was too low to start. It's on the charger,I'll shoot for Thursday around Noon for the test flight. (I'm SO nervous!) If THIS doesn't do the job,I don't know what to do next. I can order a very basic carb for an early Ford 289 or 260 for around $165.00,recon,but it might end up being a Holley. I don't know when they switched from Holley to Motorcraft on the little V-8's. Maybe by starting with a new carb,and changing the jets,metering tubes and power valve,I can get it to work right. IF this doesn't work.

   Speed

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Speed...I like the adjustable main jet on the S&S...Reminds me of my first "moto" at age 14 (Nevada scooter license era), a 1955 Allstate/Cushman with a Husky engine and vintage Tillotson carburetor.  It had an adjustable main jet, lots of fun to dial, made the rider more in step with the engine's mixture process.  This was helpful training for a later career that involved a lot of carburetor adjusting and jetting...

Good luck on the BroncWorth carburetor.  The early small-block Ford engines were Autolite or Holley carburetors.  Can confirm model years for the Autolite if you need that info...Autolite evolved into the Motorcraft era, essentially the same design.

Moses

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The deal on the S&S Shorty E fell through-the guy's son "appropriated" it to run on his Sportster. I shopped around on eBay,but the best deal I could find was JUST a used carb for $100.00,BIN. Not such a great deal since the enrichener lever and plunger were gone,no manifold,no air cleaner,and it looked like it'd been dropped into the oil sump. For what it'd take to make it work,I could do a LOT of work on my stock carb. Once I have the BroncWorth worked out,maybe I'll work up the $40.00 and get the "Fix-it" kit and see what I can do to it,or if I can cover it financially,take a ride up to Boise and look up the CV Harley Guru and get it "worked"....I'm told this guy can make the bike run like it should,get my mileage close to 50,and get better power than it has now. (Which is already plenty for the way I ride.)Probably costs cubic bucks,but if he does what they SAY he does,it'll be worth it. 

   You mentioned the "Restoration" line of thought,and I'm with you on that,mostly. I see a LOT that I want to change on my bike,mostly bolt-on and appearance stuff.

   Crossover dual pipes,short glass pack mufflers,painted high-temp flat black,with stainless steel tips,kick starter,mini-spring post and T bar with a Police solo seat,early style air filter with a K&N element,original style "FL bars" like the 50's Police bikes used (only ONE piece bars,with wiring dimples),a Knuck style luggage rack on the fender,and some old school BIG leather oval saddlebags. My bike,with these improvements,would be everything I want in a bike.

   Speed

 

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Nice, Speed...I like the Road King (without a rear pillion seat) and the Fat Boy...You have that classic look in the FLSTC, too.  Great taste!

Moses

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Actually,I was looking for a Road King Classic when I bought this one,but the one I wanted (lowest price of 3) was still $1,000.00 more than I could pay,and the seller had a specific need to get that price. Dutch spotted this one on Craigslist and suggested I go and look at it. Once there,I was impressed with the seller's honesty and integrity (He pointed out EVERY thing that needed attention.),and the price was in my range;I asked if he'd take $500.00 less for it,and he agreed,AND he filled the gas tank on it for me,at no charge. This bike wasn't what I really wanted,but I like it a lot anyway. One thing I've always liked about Harleys is that you can easily do a lot to 'em to make 'em pleasing and comfortable to YOU. (Well,it USED to be that way-these newer ones are harder to work with-too complicated.)

   I'd thought about spending the money to build a complete aftermarket "V-Twin" Panhead,with an 88" motor and the rest (except for disc brakes and other upgrades-32@ alternator,electric/kick start,LittleJohn "5 speed-in-a-4-speed-case" trans.) would be traditional '48 Pan. But THAT would have taken all of a year to paint and assemble,so I took (what I THOUGHT was) the easy way out. I may STILL do that later on if I should get another chance.

   Speed

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