Do I have a bad pump?

[venture83_98]

Finally got the '86 running well enough to sync. I was using the carbtune do loaned me and got it pretty close when I ran out of time. I came out the next afternoon and the bike would not start. Cranks fine, but won't fire. It will run for a second or two with a shot of starting fluid.

I started thinking a had a fuel delivery problem, so here is what I have checked:

Power to pump is ok.

opened all 4 bowl drains, got no fuel out of any.

put fuel hose into a gas can and turned on key. ran for 2-3 seconds. pumped fuel out fine

 

if hose is connected to carbs, or just blocked by a finger, I get maybe half a click. I also repeated all of the above with a new line going from the pump directly to the carbs. Same results. Am I barking up the wrong tree?

 

Could I try putting a fuel supply above the carbs and seeing if it runs on a gravity feed?

 

****Just pulled my carb slides, and the needles have a whiteish powdery substance on them that was not there when I reassembled the carbs. I am guessing this is related???

Edited September 29, 2013 by venture83_98
added info

[GeorgeS]

did you check the master idle screw setting ?? Turn it " IN " might start.

 

did you make sure you had some play in the " Pull " cable before starting the

sync proceedure ?? (( With master idle screw, just makeing contact, to linkage assembly, you should still have some " Slack " in throttle " Pull " cable. If not, your SYNC, is Way out of adjustment.

 

Check the " Ignition Fuse "

 

Open one of the Carb bowl drain screws, turn key to ON, is the pump, pumping fuel out the carb bowl drain hose ???? IF so, the pump is ok.

If not, fuel filter might be plugged, pump might be bad, or worse yet, you might be

" Out of Gas " !!!!

 

Is it out of gas ??? :whistling:

[venture83_98]

did you check the master idle screw setting ?? Turn it " IN " might start.

 

--- Yes, I did.

 

did you make sure you had some play in the " Pull " cable before starting the

sync proceedure ?? (( With master idle screw, just makeing contact, to linkage assembly, you should still have some " Slack " in throttle " Pull " cable. If not, your SYNC, is Way out of adjustment.

 

--- done before I even started

 

Check the " Ignition Fuse "

 

--- would that keep it from sparking? I have changed the plugs and also checked each wire with a plug on the block to check for spark.

 

Open one of the Carb bowl drain screws, turn key to ON, is the pump, pumping fuel out the carb bowl drain hose ???? IF so, the pump is ok.

If not, fuel filter might be plugged, pump might be bad, or worse yet, you might be

" Out of Gas " !!!!

 

---pump to carbs with temp line, no filter, drain open: getting no pump noise and no fuel coming out drain.

 

Is it out of gas ??? :whistling:

 

----That crossed my mind. wouldnt be the first time ........

 

 

I have also pulled the line from the tank to the pump inlet and it seems unrestricted. Glad I have a detached garage......

[GeorgeS]

Ignition fuse, powers, several items, The TCI, the 4 coils, the Fuel pump, and a couple of other non discript " relays "

 

Basicly, it kills everything, except the starter motor. ( all the lights will still work though , and the radio )

 

Also check the Ignition fuse with a meter, even if fuse not blown, make sure the fuse holder is makeing good

contact, to the fuse. ( if you still have the stock fuse holder ) Those clips, are known to cause trouble !!!

Also, they break OFF , easy.

[venture83_98]

fuse box has been replaced. checked power on fuse, seems ok. battery is at around 12.39v static. had 11.75v at fuse. I really dont think it is power related. I had NO fuel coming out of any float bowl drain with the key on. I actually removed 2 of them completely.

 

I think either the pump wont push any pressure, or something clogged the fitting on the carbs before it seperates to the 4 lines. I also updated my original post to say i noticed a whiteish powdery residue on the needles that was not there when I started adjusting. It is only on the needles and does seem to make the slides stick. I do have brand new JBM diaghaprams.

[Trader]

nevermind....I was thinking fuel filter but you said you have flow...just not very strong.

It might be the pump is weak.

 

but then...what do I know!

[bongobobny]

Hmmm, clogged fuel filter? Try the finger thing on the fuel pump to see if it acts the same. If not, i.e. takes several clicks to make it quit, then you have a pressure drop across the filter...

[venture83_98]

Hmmm, clogged fuel filter? Try the finger thing on the fuel pump to see if it acts the same. If not, i.e. takes several clicks to make it quit, then you have a pressure drop across the filter...

 

I ran a line from the pump to the carbs, no filter. acts the same. Pump won't pump if any thing blocks flow. pumps 3 times if hose is left unconnected.

[Yammer Dan]

Where is filter??

[venture83_98]

Where is filter??

 

on my garage floor. removed for testing. will replace it when i figure out issue

[bongobobny]

OK then yes, your fuel pump may be wimping out. Does the pressure feel like around 7 psi or so??

[venture83_98]

OK then yes, your fuel pump may be wimping out. Does the pressure feel like around 7 psi or so??

 

When I just have the hose going into an open container, yes. It is in 3 pulses, but does have decent force.

[Yammer Dan]

I don't understand the 3 pulses. Should do more than that. You can carefully take them apart for cleaning but I can't see it helping much if it is starting to pump.

[Yammer Dan]

Mess of them on fleaBay but somebody must have told them you might need one.

[venture83_98]

I don't understand the 3 pulses.

 

I dont get a steady stream from the pump. I get a shot of fuel with each click......

[GeorgeS]

Yup, sounds like a bad pump. Check into the low pressure pumps at auto parts, store, I think there are two models that will work. Cost a lot less then an new OEM pump.

 

I'm going to install one of those on my 08 RSTD, when I get to it.

[venture83_98]

Yup, sounds like a bad pump. Check into the low pressure pumps at auto parts, store, I think there are two models that will work. Cost a lot less then an new OEM pump.

 

I'm going to install one of those on my 08 RSTD, when I get to it.

 

 

already have one being held at o'reilly's. The mr. gasket 42s still the best choice for a Gen 1??