Runs only on Choke???

[FxdGrMind]

Ok 10+ yr old V twin Kohler 16 hp motor.

I ran it the prior w/e... no issues. 7 day's later ....

It will run, but only on "Choke" and then smokes like a BUG SPRAYER!!!

This happened 2 years ago also. Then I changed filters, Oil and plugs and all was good. This time no change.

I'm suspecting the fuel pump, but I ran it with the fuel line disconnected flowing into a cup and fuel flowed.... Maybe not enough??

Any thoughts?

 

[Scooby074]

What colour is the smoke?

Check and clean your carb as a start. Then go from there.

 

[PHIL850]

I agree with Scooby. It sounds like your Main jet is plugged up and it is running
extreamly lean. turning on the choke richens things up enough to get her to run.

Pull the fuel bowl off the carb, clean out all the sediment and junk in there,
remove your main jet and blow it out clean and reassemble the whole shootin
match.

Ciao, Phil

 

[KennyV]

I'm with Scooby & Phil on this...
drain the carb, water will set under the fuel...
and then check the fuel level in the carb (float level)... KennyV

 

[FxdGrMind]

I had pulled off the top of the carb and all looked clean as can be... I guess there might be water in the bowl...

I'll head back out and fully disasemble...

 

[Egon]

Play with high speed jet setting.

 

[FxdGrMind]

Well.... can't fully disassemble... bolts are on the bottom and I'd have to take the fairing off the motor... which means I might as well just pull the whole thing.... GGRRRRR

I checked the valves for open/stuck, but all 4 work fine.

I checked the fuel pump again, disassembled and all is in order there, plenty of fuel flow when I re-assembled and turned it over. Nice flow.

Went back and tried it all again... still will not run unless on choke.

And it is WHITE smoke.... GOBs of it.

I noticed it would backfire up the carb just before starting on choke now though.... does that symptom help any???

Cheers

 

[sunnyside360]

My 90 year old neighbor had the exact same problem as you. Turned out he used some really old gas from a can stored in one of his sheds. Besides being old, it was very dirty and had water in it. The gas filter was clogged and had a hole allowing dirt to get to the fuel pump and then the carb.
Had to flush the tank, replace the filter, and clean the carb.

 

[Just Bill]

I had the same problem after letting a mower sit over the winter.
I made a trip to walley world and bought a bottle of carb&injector cleaner.
I put half in 5 gal. of fresh gas and after a few tanks full it started and ran
better than it had in a long time. Give it a try its cheap and it might save you a lot of work.

 

[FxdGrMind]

Well, that's not it..... New filters..(all) and I just put gas in it from the gas station. It goes through a lot of gas every year, so i don't have much around very long.

I'm baffled, nothing I have done... clean carb, plugs, fuel pump, replace all filters, change oil. and to top it off, just pulled the valve covers and checked rockers, valve operation and spring tension.

That's as far as I can go without removing the motor from the chassis.

Thanks for all the input. I'll be headed to the shop tomorrow after work.

 

[tjack75]

one possibility:
If there's a leak between the carb and the manifold, air will enter there without pulling gas in. Closing the choke will suck gas in and it will run, sort of.
Check for a loose carb or a bad gasket. Good luck.

 

[westbrooklawn]

Buy a can of "Seafoam" at you local auto parts store and run some in the gas tank... I'm not saying it will work for sure, but it has worked for me in the past with similar problems.

I'm not a big fan of additives, but this stuff really does work.

 

[Ken Cunningham]

I would pull the carb off and clean out all the little passages with a small diameter wire. You probably just have a clog somewhere.

 

[tjack75]

White smoke usually indicates oil burning as opposed to excess fuel. Is the oil level too high? Does the smoke increase when the motor is tilted out of vertical? Check the compression for worn rings. How old is the motor?. With black smoke, a stopped-up gas cap is suspect. With agitation or heat, pressure builds in the tank and forces gas through the carb, producing black smoke and flooding.
Did you put 2-stroke mix in a 4-stroke? This causes lots of white smoke.

 

[J_J]

If that carb has a fuel solenoid in the carb, take it apart and clean it. Otherwise, take out the main jet and use a wire to clean it out.

 

[sunnyside360]

Well, that's not it..... New filters..(all) and I just put gas in it from the gas station. It goes through a lot of gas every year, so i don't have much around very long..........

It is possible to get bad gas from a gas station. Last summer I had trouble with a new 4-cycle string trimmer immediately after filling it with gas I had just purchased. In addition, my 3 mos old GMC pickup truck suddenly was running rough with no power as I had filled it at the same time I got gas in the 5 gal containers. To make a long story short, the new gasoline was bad. Contacted the gas station and they said others had complained also and to return the gas if I wanted to so I did. Got gasoline elsewhere and all problems were resolved.
I was over at a local ATV dealer recently and a new ATV had just been repaired. Service guy said it was bad gasoline. Just had to drain the tank and put new gasoline in it and all was okay.
Also, my neighbor is a state trooper and he said they have been getting an inordinate number of calls reporting bad gasoline.

It's worth it to try a different source of gasoline.

 

[jinman]

Bite the bullet. Do what you have to do to remove the whole carb and clean it. I use Berryman B12 Chemtool, but there are several good carb cleaners. It only takes a tiny bit of trash to clog an orifice/jets. Get the carb clean and make sure the fuel lines going from the fuel pump to the carb are also free of debris. Your symptoms are exactly those of a clogged carb. If it were a little worse, your engine probably would not run under any conditions.

If you can't get it fixed, take it to a reputable mower shop. This time of year their business is pretty slow, and you should be able to get your mower fixed quickly.

 

[Iplayfarmer]

Buy a can of "Seafoam" at you local auto parts store and run some in the gas tank... I'm not saying it will work for sure, but it has worked for me in the past with similar problems.

I'm not a big fan of additives, but this stuff really does work.

X 2 for Seafoam.

I finally ordered a case of it from the local parts store since they didn't stock it on the shelf.

 

[Scooby074]

Your right Jim.

Im firm believer that theres no such thing as a miracle in a can that you can add to your gas tank.

Carbs have to be removed and dipped. I understand chemtool is good, however i use CRC's dip i believe.Look for something with Methylene Chloride. I got it at NAPA. Really nasty stuff, wear gloves.

Soak carb for30-40 mins. Remove all the needles, jets and welch plugs taking note of their position.Then run a SOFT BRASS/copper WIRE through the passages. Then redip and soak 30 min.

Wash with hot water and soap.

Flush carb with aerosol carb cleaner.

Install carb rebuild kit.

Reinstall back on motor.

Thats my typical procedure. It fixes 90% of carb issues. Sometimes carbs are so bad that not even that procedure will fix it. And the carb needs to be replaced.

I suspect your running rich white smoke. Pull your plugs and check. Usually having to use the choke indicates a lean carb condition, but i think your getting too much fuel now. Is there puddles of fuel in the intake?

 

[FxdGrMind]

Well, Stopped by the shop. Talked with the mech's....

They think it's fuel contamination... seems that it's a recent common issue here as of late....GRRRRR

So I'll be disassembling the carb again, removing all the items, fuel and cleaning all the orifices....

Seems that there is some sort of solinoid (Sp?) valve, I'll have to take that off and see if I can clean that too.

Well at least, I'll have a project to attend to this coming rainy w/e...

The key for the mechanic, was that I had taken fuel from the tractor and used it in my Honda mower where after 3.5 hrs of running had indications of what they called "Detonation" from the "Bad fuel".

So now I need to figure out what to do with 4 gal of bad fuel.... any ideas?

One guy said dump it in the oil recycle... YEIKERS!!!! flame hazard!!!