MNSBR: Zuma No Start - MNSBR

Jump to content

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

Zuma No Start help!

#1 User is offline   Douglife Icon

  • I Should really edit this.
  • PipPipPipPip
  • Group: Member
  • Posts: 521
  • Joined: 20-August 06
  • Gender:Male
  • Location:Plymouth
  • Ride:01 GSX-R 750 - street 01 SV 650 - track

Posted 04 April 2015 - 06:52 PM

2003 zuma, ran last fall didn't start this spring...

What I've done so far:
- Cleaned carbs (had it apart about 4 times now just to make sure)
- Drained fuel, added fresh gas
- New spark plug
- Made sure fuel is traveling to carb
- Checked spark

I can get it to run sometimes by messing with the air/fuel screw and idle adjust screw. Usually it just revs to high and I back off the idle screw and it will run for a couple seconds then just die. There doesn't seem to be a happy medium.

I have a feeling it is probably just a matter of figuring out the setting for the air fuel screw and idle adjust screw, but wanted to see if there were any other obvious things to try.
0

#2 User is offline   fakehatch Icon

  • Beansnappers
  • PipPipPipPipPipPipPipPipPipPipPipPip
  • Group: Member
  • Posts: 5,756
  • Joined: 16-May 05
  • Gender:Male
  • Location:Chaska, MN
  • Ride:2003 Yamaha Zuma, Shizzle4LYFE, 1982 Honda Nighthawk cafe

Posted 04 April 2015 - 09:50 PM

Air filter dirty? Air filter box disconnected from carb?
0

#3 User is offline   Douglife Icon

  • I Should really edit this.
  • PipPipPipPip
  • Group: Member
  • Posts: 521
  • Joined: 20-August 06
  • Gender:Male
  • Location:Plymouth
  • Ride:01 GSX-R 750 - street 01 SV 650 - track

Posted 04 April 2015 - 10:07 PM

Air filter was pretty clean and air box was connected each time I tried to start it.

Going to grab a compression tester on Monday and see if that's my issue.
0

#4 User is offline   roadrulesFZ1 Icon

  • Group: Newb
  • Posts: 18
  • Joined: 29-March 15
  • Gender:Male
  • Location:Zimmerman, MN
  • Ride:2006 Yamaha FZ1

Posted 04 April 2015 - 11:42 PM

Did you put any fuel stabilizer in when you stored it, you could need to pull the carb and check the bowl for some green death, or it could be possible to run some sea foam through it to clean it up. If you did put in the some fuel stabilizer some times people think (if a little is good, a lot is better) WRONG, putting in too much stabilizer is worse than putting nothing at all, it turns into a red jelly in the bowl of the carb, (speaking from experience) :bitchslap: and it plugs up ALL the ports in the carb to where it wont run, just like green death. If you do get it to run, it runs like shit and dies. Sound kind of like what you are dealing with. Hope I helped you.
0

#5 User is offline   miweber929 Icon

  • Runnin' with the devil
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Member
  • Posts: 3,373
  • Joined: 28-September 06
  • Gender:Male
  • Location:Woodbury
  • Ride:'17 Supersport, '13 Kymco Super 8 150, '11 Sprint GT, '10 WR250R

Posted 05 April 2015 - 06:39 AM

It sounds like a classic fuel starvation symptom. How do you know fuel is flowing? Should be a vacuum petcock and those go bad quite often with from a lack of vacuum (the line going to the intake manifold) or the simply fail internally. It should only flow when suction is happening on that manifold line.

Couple tests:

- Pull the fuel line going to the carb, aim it towards a drain pan and see if it flows gas, it shouldn't. If it does your valve is bad, about $20.

- Apply a small vacuum to the air line; if you don't have a vacuum pump, literally suck on the line and see if fuel flows at that point, it should. Be careful, a torn membrane could give you a mouth full of fuel. If nothing flows look at your line, manifold and other items associated with the petcock. Again, replace if it's bad.

If that checks out REALLY clean the carb and/or internal passages in it. I'm not doubting your carb cleaning ability but it's far different than a big bike cleaning of normally just the float bowl and jets most people do. There are a ton of tiny orifaces that take nothing to get clogged, replacements are $25 for a new one online, might be easier than re-cleaning.

See where you get with the petcock tests, but make sure you erg the air/fuel screw back to stock. If it's that finicky to get and keep running I think it's a fuel delivery issue.
0

#6 User is offline   Douglife Icon

  • I Should really edit this.
  • PipPipPipPip
  • Group: Member
  • Posts: 521
  • Joined: 20-August 06
  • Gender:Male
  • Location:Plymouth
  • Ride:01 GSX-R 750 - street 01 SV 650 - track

Posted 05 April 2015 - 07:38 AM

Petcock is working, that's how I drained the fuel is by applying vacuum to the line. When I stopped applying vacuum the fuel stopped draining.

I have the jets soaking in carb clean, but I was able to see daylight through both jets and carb clean / compressed air was flowing throug all orifaces.

I'm going to give the carb one more good cleaning and then check compression.

Also just as a sanity check, the air fuel screw should be about 1.25-1.5 turns out from fully closed?
0

#7 User is offline   miweber929 Icon

  • Runnin' with the devil
  • PipPipPipPipPipPipPipPipPipPip
  • Group: Member
  • Posts: 3,373
  • Joined: 28-September 06
  • Gender:Male
  • Location:Woodbury
  • Ride:'17 Supersport, '13 Kymco Super 8 150, '11 Sprint GT, '10 WR250R

Posted 05 April 2015 - 08:00 AM

Douglife said:

1428241089[/url]' post='1078920']
Petcock is working, that's how I drained the fuel is by applying vacuum to the line. When I stopped applying vacuum the fuel stopped draining.

I have the jets soaking in carb clean, but I was able to see daylight through both jets and carb clean / compressed air was flowing throug all orifaces.

I'm going to give the carb one more good cleaning and then check compression.

Also just as a sanity check, the air fuel screw should be about 1.25-1.5 turns out from fully closed?


That sounds about right with the air screw but someone can verify in their manual. You can squirt just a tick of oil into the cylinder to get compression back if you think it might be a ring issue.

Are you sure the bike itself is creating enough vacuum? Meaning attempt to start it and apply it manually to see if it runs better. Might be a crack in the manifold or bad connection tube. Had this happen with a scoot a buddy had I sold on the forum and had it with the Aprilia SR50 I rebuilt which is why I am leaning this way, both acted about the same and both had petcock and dirty carb issues. Hate to keep harping on those areas but again, feels like déjà vu with my experience.
0

#8 User is offline   Douglife Icon

  • I Should really edit this.
  • PipPipPipPip
  • Group: Member
  • Posts: 521
  • Joined: 20-August 06
  • Gender:Male
  • Location:Plymouth
  • Ride:01 GSX-R 750 - street 01 SV 650 - track

Posted 05 April 2015 - 08:16 AM

So to test that just pull the fuel line off and try and start it and see how much fuel flows through?

I applied vacuum from the piece of hose that attaches to the carb and it didn't seem like there was any sort of leakage, but willing to check things over again.

Also, where are you seeing Zuma carbs for that cheap? maybe I didn't search hard enough but ebay seems to be around $60-$70?
0

#9 User is offline   Douglife Icon

  • I Should really edit this.
  • PipPipPipPip
  • Group: Member
  • Posts: 521
  • Joined: 20-August 06
  • Gender:Male
  • Location:Plymouth
  • Ride:01 GSX-R 750 - street 01 SV 650 - track

Posted 06 April 2015 - 12:53 PM

Alright, Cleaned the carb again, could see daylight through all jets, all ports are flowing, etc.

Ran a compression test and got about 80psi, though I think that the (rental) gauge may be junk. Need to set it all up again and try spraying some soapy water on it to see if its leaking from the gauge or if it really is the engine leaking down that fast.

Worst case scenario would I be looking at just buying a top end kit? or is there more to this than that?
0

#10 User is offline   Gunnar971 Icon

  • Former Novice Unlimited Lap Record Holder
  • PipPipPipPipPipPipPip
  • Group: Member
  • Posts: 1,629
  • Joined: 16-February 09
  • Gender:Male
  • Location:Apple Valley, MN
  • Ride:Stark Industries Kymco 125 Super 8

Posted 30 June 2015 - 12:38 PM

so I had a semi similar issue when I picked up our scoot a few months ago. I had the carb apart and cleaned it like 3 times, could see daylight through all holes, I started going through all fuel and vaccume lines to see if there was a blockage, bypassed some of the emissions crap to see if those were malfunctioning, bought a new "auto-bystarter" (essentially electronic choke) to rule that out, nothing worked.

Finally had my old man come and check it out, we tore the carb apart again and, despite being able to see light through it, the idle jet ended up being partially clogged (just so happened the buildup was damn near a perfect circle as you looked through the jet). we stuck a small gauge wire in there and scraped out what seemed to be most of the gunk (this is after having soaked the part multiple times). Put it back together, fired her up, runs like a champ now.

I know you have had the carb apart a few times now, but that may be worth checking one last time.

Can you get the scoot to idle at all? if you add throttle when you crank, can you get the scooter to run with 10-20% throttle applied? If so, you are bypassing the idle jet and that is likely your issue and worth checking again.
0

#11 User is offline   wotan Icon

  • Shot out of a cannon > squeezed out of a tube.
  • PipPipPipPipPipPipPipPip
  • Group: Member
  • Posts: 2,436
  • Joined: 12-May 05
  • Location:hud-town, wisconsin
  • Ride:Aprilia RSV

Posted 30 June 2015 - 01:55 PM

Spray some brake cleaner around the intake when trying to start it. I bet it's cracked somewhere and sucking tons of air. Pull the airbox off and plug up half the carb throat with a rag. It should start and run. I've had this problem with a few scooters -- hairline cracks in the cheap carb boot or airbox.
0

Share this topic:


Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

1 User(s) are reading this topic
0 members, 1 guests, 0 anonymous users