OH CRAP!

running the 750 seca this afternoon enjoying the beautiful weather...

on my way towards the house, i felt as if i was bucking a gusting headwind when in all actuality i was loosing power...

i had to slow and downshift to make a 90o turn and she died. i thought, maybe its out of gas (although the fuel gauge shows 1/4 tank) so i flipped over to prime for a second or two, and then to reserve...

i got it to start using the choke but it didnt run too good. it had a serious putt-putt sound going on. kind of reminded me of those smoky scooters they show in the old movies or maybe a golf cart...

got to the next intersection where i had to turn again and even with full throttle it kept losing more power to the point it stalled. i barely got it started to get thru the intersection up to my sub where again it putt-putted down the street...

i popped it on the center stand and the oil level is good. i can see fuel on the gas cap side of the tank and it cranks very easily...

this bike fired with up with a fraction of a second application of starter everytime ive started it (other than just today trying to get home)...

im wondering if there was some crud in the tank that is blocking the newly installed inline fuel filter (havent checked it yet) or (hopefully not) the carbs got some gunk into them from the lower fuel level...

i HATE messing with carbs...

ive got the new fuse block in and it all checks out and it cranks and its got good spark that i can tell so its not electrical...

crap. i dont want to be down with THIS bike too...

 

Sounds very similar to the problem I'm trying to sort out with my wife's bike. I'm about at my wit's end with what it could be. I'm down to swapping parts between her bike and mine trying to find whatever is causing this. As a matter of fact, I was just reading up on what all is involved with swapping pick-ups. I think that's next. After that, I'm swapping carbs.

 

See if it will fire on Starting Fluid.
See if it will fire on Propane Gas into its airbox.

If it does ... something clogged.

Also make sure that the Vacuum Hose to the Pectcock is REAL Vacuum Line.
A hose that collapses under Vacuum will make the Bike act like its out of gas.

 

sorry to hear about your problems Lt, i hope you made it to the mail box.
good luck, wizard.

 

hmm... gradual loss of power... sounds a lot like a fuel delivery issue.
the plastic filter that sits on top of the petcock can get gummed up and not allow enough fuel to flow through once the level drops low enough.

something could've got into the petcock, too.

does it die if you just leave the petcock on PRI?

 

no problem before fitting new in-line filter, perhaps-------?

 

Double check to make sure that you didn't put a kink in the fuel line when you installed the inline filter,as you said that it ran well prior to that.

 

yes it ran good prior to the filter but it didnt start acting up until i had put about 18 miles on it tonight...

me thinks the petcock filter might have some gunk around it...

 

A couple of 'easy' fixes to try first:

a) Put some gas in it. My xj runs horribly on a low tank

b) leave the petcock on 'prime' when its running, see if that eleviates the issue. If it does, replace that vacuum line from the carb to the petcock.

c) if b doesn't work, check that you installed the inline filter right. It may sound stupid, but they can't work backwards.

d) check the filter above the petcock. This can be done by removing the tank, putting it on its right side on a soft towel and taking the 2 screws out that hold the petcock in.

e) I have had a faulty in line filter before. Take it off and try to blow in one end. Make sure you have good flow.

f) Check the vent on the top of the tank. I had this exact problem with my Honda CB 350F and it was a rust fouled vent. You can know for sure by popping the gas cap and leaving it open when riding. If this solves the problem, take the cap apart and clean it. It's actually very easy, just do it somewhere clean as there are many small parts involved.

Let me know how this goes, so we can go further if we need to.

Stephen.

 

At least check the Inline Filter for it being filled.

An "Airbound" Inline filter will act like a Gasa Line runninng close to an exhaust manifold. A cold kind of "Vapor Lock"

The Bubble in the Fuel Filter cannot compress. It just tries to rid itsself of the bubble.
Since there is enough Fuel in the system to keep the lower end filled the Bubble tries to rise into the tank.
When it can't and the pressure inside the Fillter is greater than atmosphere ... Fuel flow is curtailed.

Beenie Screens; too.
If the Float Valve Beenie Screens are clogged or partially clogged the Fuel Supply is greatly curtailed.

Just remember the fateful words uttered to me by a long-time Yamaha Tech with well over 25 Years working on these Bikes:

"It's the Carbs. It's always the Carbs."

(The sooner you get them off and look inside ... the sooner you'll be closer to not having the bike slow-down and quit on you)

 

i dont WANT to go inside. i dont have the patience for that stuff...

i put 62 miles on before the filter and another 12 since the filter. the sputtering and power loss started 10 after the filter...

im thinking its probably the fuel level since its now reading 1/4 or less...

im hoping the petcock filter is all i need to clean because i need this bike to run 100+ miles without issues...

 

Definately look at the petcock. I had a similar kind of problem and found a small bit of something lodged in the petcock. Would allow fuel past so it looked good but not enough to keep her running.

 

pulled the petcock: clean filter inside
disassembled petcock: found nothing out of the ordinary
set tank over acceptable (environmentally acceptable!) catch basin and set petcock to PRIme: fuel flows cleanly and evenly

trimmed a bit of fuel line off to get rid of minor (and i mean very minor) kink...

put it all back together and started it up. it will run (not super smooth) with some 'enrichment' added but then dies without it...

put the petcock on PRIme while the bike is running and NO visible fuel flow into the filter. no visible fuel flow into the filter with it set to REServe or ON either...

i dont want to pull those damned carbs off. but then i think there should be better fuel flow from the petcock as well...

 

Your fuel filter should fill with fuel. Even IF carbs are all stopped up.

You need to get fuel flowing through there.

 

Agreed, if the petcok is working fine, the inline should fill on prime. If it doesn't check it, replace it, or temporarily remove it and put a fuel line joiner in and see if that resolves your issue.

 

I'm thinking you have to pull the Carbs and get the Beenie Screens on the Inside of the Float Bodies cleaned of whatever got through to contaminate them.

It don't take much to have the Beenie Screens get fouled and prevent fuel from getting passed them to fill the Fuel Bowls.

Sooner or later you are going to have to check them.
I know pulling apart the Carbs is no fun ... while you are doing it.

But, think of all the fun you could have after you get your Carbs Cleaned and the Bike tuned-up real nice.