engine seems to be starving for want of fuel.

Joined
Apr 7, 2007
Messages
624
Location
Tacoma, wa
I just got finished cleaning the pilot jets and once reassembled. tried to start it and nothing.......I used some starter fluid sprayed into the snorkels and it ran fine. today I took the fuel hose off the metal tube that's routed to the fuel pump access plate. turn on the ign. and the fuel pump kicked in for about a second and then stopped. ( just like it had before I dove into the carb removal) a small amount of fuel was delivered, but the fuel filter doesn't fill up when reassembled. I'm sorta perplexed by this. does anyone have an idea what's the problem?----------up date the fuel cut off has been off of the bike for a few years, and I replaced the fuel pump with an OME pump about three years ago
 
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Joined
Aug 11, 2013
Messages
3,507
Location
kankakee
Bike
R1200rt
check to see that the fuel pump has power while running, could be a relay if it does not have power while running. What you described is normal. If the carbs had no fuel the quick on and off of the fuel pump would not be enough to get it all 4 carbs filled to start. Get a simple 12v test light, digital volt meter is always better
 
Joined
Aug 6, 2015
Messages
328
Location
Peoria, Illinois
Bike
1995 ST1100
STOC #
8866
If you cycle the Run/Kill switch while the key is in and on, it should deliver a second of running each time - a few cycles and you can fill the bowls enough to start it in case they're bone dry.
 
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Joined
Apr 7, 2007
Messages
624
Location
Tacoma, wa
Haven't had a chance to check if the pump's powered all the time while the ign. switch is in the run position. a bit unsure at which connection to test for this.. I have two connections that are terminated in a plastic sleeve/cover. one is in gray plastic, the other in a black the third is clearly a ground ( all three have a plastic sleeve that obscures their color coding). which connection point is the correct one?... on a side note this am I went out and got some fresh gas. disconnected the fuel supply hose from the bikes tank and inserted a funnel in the hose and filled it with gas and let it stand as to create a 13" head pressure. sat all am this way . just a few minuets ago I reconnected it back to the tank and the bike started right up, but only ran about 3 minuets before stopping from , what I think was lack of fuel. I'm strongly suspecting that I should of cleaned the fuel float valves while I had the carb set off and opened. my suspicions are that the needles are stuck with the aged fuel that was in the tank for 9months. the same fuel that prompted me to remove and clean the pilot jets. does it seem logical to anyone that all four fuel valves would be stuck ? when I installed the carb set I did blow into the fuel supply hose and it seemed to be blocked- I would of thought a little bit of air would pass, since the carbs were cleaned and devoid of any fuel.
 
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Joined
Aug 11, 2013
Messages
3,507
Location
kankakee
Bike
R1200rt
when the key is turned on it energizes the fuel pump for a second or two, it will not turn on until the engine is running, not key on engine off. Get a test light , ground one side to neg on battery. Hold the other end to any wire on top of the fuel pump. Turn the key on and off till you find the power wire for the fuel pump. You wont damage anything, once you found the power wire start the engine with the aid of whatever and watch the test light to see if the pump has power while running. turn the key on and off multiple times which should fill the carbs. If the carbs are ok it should start and run till the fuel bowls empty out. all the time checking for power at pump. This will help diagnose a fuel supply problem (electrical) or a carb problem
 
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Joined
Apr 7, 2007
Messages
624
Location
Tacoma, wa
just checked for power while the bike is running.....power stays on. ( btw, it's the gray plastic) so I figure that I have to remove the carb set and will probably elect to just change out float valve needles and seats. and since the pilot jets are so reasonable, they along with the bowl gaskets will be replaced too. thanks to all for the help
 
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Joined
Aug 6, 2015
Messages
328
Location
Peoria, Illinois
Bike
1995 ST1100
STOC #
8866
When I redid mine, all four needles were stuck and gunk in the bowls. You need to pull those needles and the seats and the mesh filter above the seats and clean it all. I only had to replace the bowl gasket as 2 were cut, but the rest of the parts cleaned up well enough.
 
Joined
May 27, 2013
Messages
162
Location
Newmarket, Ontario north of Toronto
Bike
1999 ST1100
There have been a number of posts on the vacuum petcock and how that prevents/starves the engine of fuel. Not saying that this is your issue. Generally with this problem, some fuel does get through to the carbs allowing the engine to run, just not enough fuel for hard acceleration or regular acceleration when riding two up. If you haven't removed this petcock, it's worth doing as it will at least eliminate this problematic piece from being in the equation. There have been numerous posts on this problem.
 
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Joined
Apr 7, 2007
Messages
624
Location
Tacoma, wa
Sorry JC, I should of used more precise language. by using "fuel cutoff" in post1, I was in fact talking about the "vacuum petcock"
 
Joined
May 29, 2008
Messages
252
Age
75
Location
Christiana, PA
Bike
2015 Can Am Spyder R
STOC #
7651
Mine acted the same way, and the problem was a tear in the vacuum diaphragm. I am assuming you checked that out. If it is bad, you can bypass it as there are instructions on this site somewhere.
 
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Joined
Apr 7, 2007
Messages
624
Location
Tacoma, wa
there's no vacuum petcock to check. I've decided that the float valves are gummed up to the point of stopping most fuel from passing....started up rough on the 1st of this month- couldn't address it right away, and when I came back from a biz trip it wouldn't start at all!. this seems to of stemmed from ME allowing the bike to sit for much too long without running. currently waiting on carb rebuilt parts (there isn't much more of a pita that this-and, frankly I was hoping to avoid it.) once I get the last few I'll launch into it. right now the bike is all prepped for the carbs to be pulled and worked on. I'll of course, report back for those who are interested. garage is all cleaned up and the lighting has been serviced( two car garage with 1184watts in florescent lighting...almost need sunglasses when I walk in.
 
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Joined
Aug 6, 2015
Messages
328
Location
Peoria, Illinois
Bike
1995 ST1100
STOC #
8866
Good luck with it - that's exactly where I was a month ago. But my fuel flow wouldn't shut off, and had cut bowl gaskets from a PO's hurried "repair". Those gaskets sit in a groove in the bowl, but the groove won't hold 'em in place. Go to your local auto pars store and get a little can of gasket sealer. Brush it on thinly in spots around the bowl and once it sets up, you can then secure the gasket in place while you secure the bowl screws. Be careful not to get carb cleaner soaking on the diaphragms - best to leave 'em alone if you don't need to get into them. Ultrasonic cleaners work great on the jets, fuel inlets, screens, bowls and needles. Harbor Freight sells them and it's a great addition to the garage.
 
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