Sputtering and engine cutting off, 2002 S4

Started by Qomomoko, May 17, 2020, 05:46:40 PM

Previous topic - Next topic

Qomomoko

2002, Monster S4.
Had been running fine, engine wise for quite a while as in years.
Did some electrical work, added a new horn and new wiring for improving headlight performance. This was done thru a kit from Easter Beaver. I AM NOT SAYING THE KIT DID THIS. I disconnected battery fully every time I was doing work.

Back to current issue. As shown in the video running first gear at 7k rpm and then start sputtering and finally dies off. I can keep her on by giving some gas and then she comes back.  Same thing with 2nd gear but at times it stays alive.

The main switch (30A) fuse did give up about two years ago. I replaced it and looked at it when I was doing the electrical work recently. one end looked burned but the fuse was still good. Just and FYI.

Thanks.

Video link below, forgot how to embed




Howie

If you stay under 7k are there still issues or is it as bad?  Anyway, I'm thinking either fuel contamination or a clogged fuel filter.  While in there check the hoses.

Qomomoko

at first it was only at 7k rpm but now it was happening at a larger range

I hope and think fuel lines and filter are culprits. My Gas cap/lock mechanism looks horribly corroded.
I have already replaced the cap with a used one but think it is time to do it right. Maybe even try and fix my non working low fuel light.

Speeddog

Open gas cap
Put hand over opening
Turn key on

If your hand gets sprayed with gas, there are problems inside the tank.

If not, look inside and see if the plumbing inside is leaking while the pump runs.
- - - - - Valley Desmo Service - - - - -
Reseda, CA

(951) 640-8908


~~~ "We've rearranged the deck chairs, refilled the champagne glasses, and the band sounds great. This is fine." - Alberto Puig ~~~

Qomomoko

#4
Electrically, looks good, no stuff loose and cleaned the fuse box, replaced fuses, and then re-replaced the old ones LOL

Why?

Because I was paranoid and the new ones looked like there were the same (except for color) ; were rated for different Amps. thus different colors

Looked again today and saw it was mostly my in my head the above.



Back to the tank:

The fuel filter looks corroded/stained from the outside of the filter; it was dangling inside the tank and I positioned it back onto the holder.

A breather hose was broken; I cut it and reattached. Now the engine runs but dies within 5 seconds. I DO NOT UNDERSTAND.



Will keep looking at the tank and see what else might be wrong with the tank, figure next step is draining tank.



The breather hose is one of the two that hooks up to the top of the gas cap. Doubt it was this that was making the sputtering.


ducpainter

When was the last time the filter was replaced?
"Once you accept that a child on the autistic spectrum experiences the world in
 a completely different way than you, you will be open to understand how that
 perspective
    is even more amazing than yours."
    To realize the value of nine  months:
    Ask a mother who gave birth to a stillborn.
"Don't piss off old people The older we get, the less 'Life in Prison' is a deterrent."



Howie

Rusty filter points to two areas:
         Filter is old.
         Filter has seen water.  Bikes do not run on water.

See my first reply, and also Speedog's


Qomomoko

dang,

Filter replaced about 5 years ago.

I have ridden in rain but not recently, not within 1 year and have done 4 tank fills in last month before acting up.
But the water makes sense or at least very hi humidity which also makes sense and then condensing in tank.

Did the hand spray test, no  spray.

Speeddog

Did you look inside while the pump's running to see if there's anything unusual ?
- - - - - Valley Desmo Service - - - - -
Reseda, CA

(951) 640-8908


~~~ "We've rearranged the deck chairs, refilled the champagne glasses, and the band sounds great. This is fine." - Alberto Puig ~~~

GregP

Sorry for the thread jack: I have an intermittent flat spot/bog on my 01' S4 at 6-7k. Mostly under hard acceleration. Considering checking and changing the fuel filter. Did a little searching and can't find basics on this process. I'm guessing I have to take the tank off the bike and remove the innards to get to the filter. Am I correct? 

Don't expect much and you won't be disappointed.

Qomomoko

#10
I will post pics with which line is which (breather hoses ( one is overflow (breather #2) and other is a breather hose that partly seals when the fuel cap is closed(breather #1)))
Also the M(FEED) and the R(RETURN) (M is the furthest back in S4 02, I checked it by blowing on the outlet of fuel filter and seeing which spicket blew air)

my (what I am calling overflow ) is very very clogged.
I see how the tank not breather might not allow for fuel pump to suck as it would then create negative pressure IF the tank were to be sealed.
Also the clogged was probably caused by the corroded/degraded fuel cap and the corrosion going into the OVERFLOW Feed.

I will do pictures with labels but below is some pics to get a gist.

I would love to remove my low fuel sensor and attempt at fix it but seems partly stuck. Also the tank was more dirty inside than I would like..
within imgur I have a description of each spicket/nozzle.

First pic:

8 o-clock (overflow breather 2, 5 o'clock with rubber top overflow breather 1




Qomomoko

So here is pics labeled.

I do not see how that clogged breather is the immediate cause of my sputtering, if is, can you guys help me understand?

Still loosing the grudge in the line but filling line with fuel and little by little stabbing it with a cable tie.






Qomomoko

#12
Quote from: GregP on May 24, 2020, 06:24:59 AM
Sorry for the thread jack: I have an intermittent flat spot/bog on my 01' S4 at 6-7k. Mostly under hard acceleration. Considering checking and changing the fuel filter. Did a little searching and can't find basics on this process. I'm guessing I have to take the tank off the bike and remove the innards to get to the filter. Am I correct?  



Naw, just remove the fuel cap and the cap base, see pic below.
No need to remove the tank nor drain it.


Howie

Clogged breather will cause fuel starvation since a vacuum will result as fuel leaves the tank, but air cannot enter.  Bet that filter is clogged too.

Qomomoko

Quote from: howie on May 24, 2020, 03:54:55 PM
Clogged breather will cause fuel starvation since a vacuum will result as fuel leaves the tank, but air cannot enter.  Bet that filter is clogged too.


makes sense but  I tried starting the bike and running it with the fuel cap open and still died. Unless I also do not understand how the breather #1 works which seems to be semi "closed " when the fuel cap is closed. When the fuel cap is closed there is a black tab, with a little pee hole, that cover the "black tube" on breather #1. Meaning when the cap is open breather #1 does not perform its function properly.

Yeah... lol... that filter had some much in it but I was able to blow thru it both ways/sides.