I'll try to make this long story short. Week before last I tried to go riding. After just making it to the trailhead (300 feet from the truck) my Ozark started stalling (but it would idle fine). I messed with the idle setting for a while and pulled the plug and it was running very rich. Cleaned the plug a little and then reinstalled. Then it wouldn't idle but would run great mid to WOT. I packed up and went home at this point. Since I hadn't done an oil change in a while I ordered a couple plugs, twin air filter, and a dial a jet kit (since I was going to be in the carb anyway).

I pulled the carb apart the next day and chem dipped it over night. Next day drained it and blew it out with compressed air and reassembled it. Adjusted air/fuel mixture to 3 turns out, installed dial a jet, and put it back on the bike. It fired right up and idled great and revved great so I went to bed (it was 10pm). Next afternoon I started it back up and it barely idled and wouldn't rev, so I blocked the dial a jet and tried again. Needless to say, the problem is real eradic and spontaneous. Sometimes it idles fine and won't rev and other times it won't idle but will rev.

I did change and make sure I had fresh fuel (I cleaned the tank, strainers, and even filtered the fuel going into the tank)

There is only three more things that I think it could be; pinhole in the top diaphragm, hole in the float, or the float adjustment is off.

Right now I'm waiting on parts. I ordered the diaphragm, accelerator pump diaphragm, and all the o rings.

I do need the float level measurement.

Anybody got any suggestions, or solutions? I greatly would appreciate any help.

 

Sounds like you are on top of it with regard to your carb. I did pick up on one thing tho' 3 turns out on air/fuel (pilot jet). Generally the settings are 1 1/4 out. If you excede 3 turns then you need a smaller jet, If you turn in to less that 1/2 turn out then you need a bigger jet.

Here is a list that may help.

Problem: Engine idles poorly
Condition Remedy
1. Valve clearance out of adjustment 1. Adjust clearance
2. Valve seating poor 2. Replace - service seats
3. Valve guides defective 3. Replace guides
4. Rocker arms - arm shaft worn 4. Replace arms - shafts
5. Magneto defective 5. Replace magneto
6. CDI unit defective 6. Replace CDI unit
7. Spark plug fouled - gap too wide 7. Adjust gap - replace plug
8. Ignition coil defective 8. Replace ignition coil
9. Float out of adjustment 9. Adjust float height
10. Jets obstructed 10. Clean jets
11. Pilot screw setting improper 11. Adjust pilot screw

Problem: Engine runs poorly at high speed
Condition Remedy
1. High RPM "cut out" against RPM limiter 1. Shift into higher gear
2. Valve springs weak 2. Replace springs
3. Valve timing out of adjustment 3. Adjust timing
4. Cams - rocker arms worn 4. Replace cams - arms
5. Spark plug gap too narrow 5. Adjust gap
6. Ignition coil defective 6. Replace ignition oil
7. Float level too low 7. Adjust float height
8. Air cleaner element obstructed 8. Clean element
9. Fuel hose obstructed 9. Clean - prime hose

 

MAYBE WATER IN GAS. mine did that a few moths ago. I had water in my gas.

 

Thanks for all the help buckaroo50. But are you sure about the number of turns out from seated? This thread says 2 7/8 or 3 1/2?
http://forums.atvconnection.co...keyword1=ozark%20carb


This thread says 1 15/16 to 2?
http://forums.atvconnection.co...keyword1=ozark%20carb


You are talking about the air fuel mixture screw correct? Number 30 in the pic.
http://www.imagessite.com/OEM_...images/02LTF25010.gif


Also, would you happen to know the correct float setting? Thanks for the help.

 

<div class="FTQUOTE"><begin quote>Originally posted by: Youngblood250

Thanks for all the help buckaroo50. But are you sure about the number of turns out from seated? This thread says 2 7/8 or 3 1/2?

<a target=_blank class=ftalternatingbarlinklarge href="http://forums.atvconnection.com/messageview.cfm?catid=12&threadid=512400&highlight _key=y&keyword1=ozark%20carb
">http://forums.atvconnection.co...d1=ozark%20carb
</a>


This thread says 1 15/16 to 2?

<a target=_blank class=ftalternatingbarlinklarge href="http://forums.atvconnection.com/messageview.cfm?catid=12&threadid=306138&highlight _key=y&keyword1=ozark%20carb
">http://forums.atvconnection.co...d1=ozark%20carb
</a>


You are talking about the air fuel mixture screw correct? Number 30 in the pic.

<a target=_blank class=ftalternatingbarlinklarge href="http://www.imagessite.com/OEM_Images/Suzuki_atv_images/02LTF25010.gif
">http://www.imagessite.com/OEM_.../02LTF25010.gif
</a>


Also, would you happen to know the correct float setting? Thanks for the help.</end quote></div>

As a general rule of thumb without seeing the exact specs for your machine and carb is to start at 1 1/4 turns out for your pilot jet air setting. Also the general rule that if you are more than 3 turns out - change jets if you are less than 1/2 out from full in - change jets not to say that your machine may be different but 2 1/2 turns should get you there on any carb.

Not to confuse you but there is 'pop-off' pressures and needle thickness and also needle point angle that can assist in tuning a carb. Most carbs come with a generic setting that works properly for most applications but to tune it for a specific machine or application then a host of other setting and adjustments can be made to fine tune it. Just like you can buy a knife and it is sharp but you can hone it with a specific angle and make it even sharper - like razor sharp.

As far as float settings most are between 13 and 22 with most being around 16-17. If I knew your specific carb I could possibly find the exact setting or at least point you in a direction.

I can't find the Mikuni carb link but here is the Keihin link, you only need to find your specific model
http://www.carbparts.com/keihi...ning/keihin_tuning.htm

 

level when flipped upside down.

 

Thanks buckaroo50, the Ozark uses a MikuniT BS29.


Does anybody have the manual that can clarify what the air/fuel mixture screw initial starting point is and what the float lever measurement needs to be?

 

hey man
on my ozark i turned it 3 and 1/2 turns out

hope that helps

 

I did some searching on the Mikuni carb and here it is.

Start with the Pilot jet screw 2 turns out.

With the engine warmed up turn the screw in until it runs rough (too rich), then turn it out until it smoothes and then runs rough again (too lean). The correct setting is the split between the two possitions of too rich and too lean.

1. If the best idle is achieved with the air
screw less than one turn out, the pilot jet
is too small and should be exchanged for
a larger one.
2. If the engine speed does not slow after
two-and-a-half turns out, the pilot jet is
too large and should be exchanged for a
smaller one.

 

Thanks for trying to help buckaroo.

Tried it and it didn't work for me. It still won't idle but will rev (was running rich which was indicated by white smoke). I went ahead and put in the new diaphragms and orings and the smaller main jet that my dial a jet suggested. Still would not idle.

So, I took the carb all apart again and sprayed carb cleaner in all the ports and jets then I blew them out with compressed air and reassembled. Same thing, wouldn't idle.

So now I'm thinking it's a coil or a cdi unit.

Anybody know how to test a coil or cdi?