190c riding mower runs like it is on one cylinder....

[beenthere]

Seems like it was a good test. :thumbsup:

 

[DrBill]

There is something wrong and it's affecting both cylinders. I suppose the carb and manifold might need looking at again.. Whatever this one thing is, it seems to me it's major and should stand out like a sore thumb. Even with your good videos,, it's not ringing a clear bell to me about what it is ?

I guess that's why we have a forum like this,,, to try..

One more thing that I've scratched my head about is safety switches.. Going back years to my motorcycle days (we sold lawn and garden too). We had a mower here and there that had a bad safety switch that would go bad in a way that it would run , but the crossed up signal(I guess) would interrupt the ignition system while running and cause this unanswerable running condition.. In these cases, a spark check always looked good..

Just like the flywheel key info,,, I'm emptying my bucket and mentioning this just to keep it in mind in case the answer never comes up somewhere else..

There is going to be an answer to this somewhere..

Please keep us posted.. I do want to know the answer whenever this is over...

 

[mattbatson]

I will for sure keep plugging away at it, and will definitely give updates as I go and post up the final result (I know that often people ask about problems on here, and do not post up the final solution...and I understand how frustrating that can be)

I will check the safety switch, and plan to replace all fuel line also....and of course pull the carb down...this time though, all the way down.

thx again for all the help

 

[DrBill]

Thanks Matt,,, let us know the good,, and the bad too.. I hope it starts getting better.

 

[pacerron]

When you took the carb apart you said it looked clean so you only replaced some of the stuff.

Did some of the stuff include the needle valves and seats?
Jim Inman on TBN always advised that the tips of the needle valves were rubber and that they get messed up by the gas we get today even if you use an additive.

We have a L120 with over 1000 hours on it. A couple years ago the wife complained that it was running ruff. The paper clip clean out of the gas cap breather hole
worked for a while but would repeat the missing after a half acre or so. I took the cap apart. There is a splash plate under the rubber that has a shaft that rides up and down in the center tube that has the vent hole in top. It seemed to be binding a bit probably from the plastic pin scarring the tube. Rather than buying a new gas cap, I carefully drilled out the shaft hole another 1/32" on my drill press. That corrected the vent sticking problem.

The missing reappeared, always seemed to be on the side the oil filter is on ( the left side, when sitting on the seat).

I was about to get a carb kit and rebuild it, but had read some threads by Western, on TBN, and others about how great Seafoam was at cleaning carbs.
I had never used it before. My old days of using gumout on Holley 4 barrels, as a kid, made me skeptical.
The Seafoam still comes in a metal can so I was a little anxious about using it in a modern carb with plastic and rubber parts... but.
I ran 1 full tank of fuel with 2 oz. per gallon of Seafoam in it. It started running better as the fuel was consumed and was running like a new engine by the time the tank was almost empty.
It has run fine for 2 summers now, about 8 hours per week, with no re-treatment. We do use Stabil in every batch of gas now, but used it most of the time before, and always in the gas that sits in anything over winter.

I have no interest in either of these products. Just something to try if you haven't already, and you know you put your carb back together right the first time, along with putting the linkages back on properly for the choke and governor..

 

[DrBill]

I stopped by my old shop today and I mentioned this situation to them. They are much more into lawn and garden today and they have dealt with a lot of the Briggs twins.

They agreed that yes, they had seen issues like I described on the Briggs twins before. They said because of shop labor rates they had started replacing the carb with a new one rather than the labor cost of trying to fix. (I think they had some prior boomerangs and that caused that decision)

They mentioned plastic parts and o-ring issues around the main jet area at the bottom of the float bowl..

I liked hearing that maybe this had been seen before, but I didn't like hearing about the hard to fix plastic parts carb..

 

[mattbatson]

When you took the carb apart you said it looked clean so you only replaced some of the stuff.

Did some of the stuff include the needle valves and seats?
Jim Inman on TBN always advised that the tips of the needle valves were rubber and that they get messed up by the gas we get today even if you use an additive.

We have a L120 with over 1000 hours on it. A couple years ago the wife complained that it was running ruff. The paper clip clean out of the gas cap breather hole
worked for a while but would repeat the missing after a half acre or so. I took the cap apart. There is a splash plate under the rubber that has a shaft that rides up and down in the center tube that has the vent hole in top. It seemed to be binding a bit probably from the plastic pin scarring the tube. Rather than buying a new gas cap, I carefully drilled out the shaft hole another 1/32" on my drill press. That corrected the vent sticking problem.

The missing reappeared, always seemed to be on the side the oil filter is on ( the left side, when sitting on the seat).

I was about to get a carb kit and rebuild it, but had read some threads by Western, on TBN, and others about how great Seafoam was at cleaning carbs.
I had never used it before. My old days of using gumout on Holley 4 barrels, as a kid, made me skeptical.
The Seafoam still comes in a metal can so I was a little anxious about using it in a modern carb with plastic and rubber parts... but.
I ran 1 full tank of fuel with 2 oz. per gallon of Seafoam in it. It started running better as the fuel was consumed and was running like a new engine by the time the tank was almost empty.
It has run fine for 2 summers now, about 8 hours per week, with no re-treatment. We do use Stabil in every batch of gas now, but used it most of the time before, and always in the gas that sits in anything over winter.

I have no interest in either of these products. Just something to try if you haven't already, and you know you put your carb back together right the first time, along with putting the linkages back on properly for the choke and governor..

I have seafoam, and have used it on my auto's

it is easy and worth a try.
I'll let you know how it goes

 

[mattbatson]

I stopped by my old shop today and I mentioned this situation to them. They are much more into lawn and garden today and they have dealt with a lot of the Briggs twins.

They agreed that yes, they had seen issues like I described on the Briggs twins before. They said because of shop labor rates they had started replacing the carb with a new one rather than the labor cost of trying to fix. (I think they had some prior boomerangs and that caused that decision)

They mentioned plastic parts and o-ring issues around the main jet area at the bottom of the float bowl..

I liked hearing that maybe this had been seen before, but I didn't like hearing about the hard to fix plastic parts carb..

I saw these parts you speak of when disassembling, and they sure looked fine to me...
I"m going to run some seafoam through it, just to see what happens, and if that doesnt work, then I'll take the carb down.

thx again, and I'll update soon

 

[DrBill]

Matt,, this seafoam stuff is a product for erasing gum and restrictions.

You do not have gum or restrictions. You have too much fuel !

Or you have the right amount of fuel, but you don't have the right ignition to burn it..

Seafoam will not fix your issue. Your problem and " fix in a can " are several miles apart at this juncture...

 

[mattbatson]

hey, sorry, been so busy and didnt get a chance to read this before running some seafoam in the mower...
it didnt clear anything up after a few minutes of running, and I just turned it off knowing that wasnt going to work.

You are correct, the carb is already clean and seafoam is not the answer.

I will update in a day or so when I get some work done on it.

thx again