[DSB335d]

I have a 16hp v-twin lawnmower. Choke linkage works, throttle linkage works also. Spark plugs are new. Engine will not idle or stay running with air filter/box in place. If I cover the carburetor nearly completely and start it, it will run with the choke closed. I can increase the throttle up and down; again only with the carb nearly completely covered. Also at mid-full throttle the governor moves erratically "hunts".

I pulled the carb off and there was some gunk in the float bowl, I cleaned that out and made sure the throttle and choke butterfly's were clean and moved freely.

It seems like I'm not getting enough fuel. With nearly no air entering the carb it will stay running, as soon as you unblock the carb or slightly open the choke (even with the carb blocked) the engine dies.

My guess at this point is that the main mixture "jet" may have a blockage, therefore not delivering enough fuel.


Anyway thanks for your time/advice.

[ASBSECU E93]

Buy a bottle of fuel additive, add a couple ounces to a tank.

[Umi|all|day]

Replace the rod bearings

[shoei]

Originally Posted by ASBSECU E93

Buy a bottle of fuel additive, add a couple ounces to a tank.

Are you sure it's not the dreaded HPFP failure?

(Oh gawd, I remember when 65% of the forum was dedicated to that in 2007-2008)

[ASBSECU E93]

Originally Posted by shoei

Are you sure it's not the dreaded HPFP failure?

(Oh gawd, I remember when 65% of the forum was dedicated to that in 2007-2008)

That's because you're old....GRANDPA!!

[shoei]

Originally Posted by ASBSECU E93

That's because you're old....GRANDPA!!

How are you calling me or anyone grandpa??!!

[RickFLM4]

If you can't get it working properly try Southern Lawn Equipment near the fairgrounds. They seem to do a good job when my generator needs work.

[larryn]

Sounds like it could be an air/fuel ratio issue, and therefore a carburetor issue. It could be that air is being introduced through a bad seal, o-ring or gasket... Or you are flooding or starving gas due to needles being shot, o-rings messed up or gumming up elsewhere. Since you already took apart the float sand noted gunk, I assume it's not that new, but you are comfortable doing things like that.

Carburators are finicky and if you prefer to take care of it yourself, I would just suggest getting a carburetor rebuild kit from the manufacturer. Otherwise, most small engine repair places do pick-up and drop-off service.

[jtodd_fl]

Originally Posted by DSB335d

I have a 16hp v-twin lawnmower. Choke linkage works, throttle linkage works also. Spark plugs are new. Engine will not idle or stay running with air filter/box in place. If I cover the carburetor nearly completely and start it, it will run with the choke closed. I can increase the throttle up and down; again only with the carb nearly completely covered. Also at mid-full throttle the governor moves erratically "hunts".

I pulled the carb off and there was some gunk in the float bowl, I cleaned that out and made sure the throttle and choke butterfly's were clean and moved freely.

It seems like I'm not getting enough fuel. With nearly no air entering the carb it will stay running, as soon as you unblock the carb or slightly open the choke (even with the carb blocked) the engine dies.

My guess at this point is that the main mixture "jet" may have a blockage, therefore not delivering enough fuel.


Anyway thanks for your time/advice.

Did you leave gas in it for a bit without the anti-gunk stuff. Those who don't live in FL don't realize how quickly the ethanol can congeal down here. I use ethanol free gas for my equipment.

I had to do a rebuild on one of mine, but it was a much smaller engine (a pressure sprayer).

[P1]

My Echo was doing the same thing, and I took it in to get it fixed. It was literally less than $20. Not worth even doing it yourself, unless you simply want to tinker around with it.

[Mr Tonka]

If you're going to use a small engine, make it a 12 cylinder.

[jtodd_fl]

Originally Posted by Mr Tonka

If you're going to use a small engine, make it a 12 cylinder.

That's sweet. Yours? What is it from? I don't think I've ever seen a car model with a "functional" engine.

[Maestro]

Originally Posted by larryn

Sounds like it could be an air/fuel ratio issue, and therefore a carburetor issue. It could be that air is being introduced through a bad seal, o-ring or gasket... Or you are flooding or starving gas due to needles being shot, o-rings messed up or gumming up elsewhere. Since you already took apart the float sand noted gunk, I assume it's not that new, but you are comfortable doing things like that.

Carburators are finicky and if you prefer to take care of it yourself, I would just suggest getting a carburetor rebuild kit from the manufacturer. Otherwise, most small engine repair places do pick-up and drop-off service.

I seen this problem, the issue is the gas, most small engines carbs are not design to deal with the ethanol and the other crap they put in the gas today. You need to treat the gas before you put it into your small engines. With that said, doing a complete rebuild and then tuning the carb most likely will solve the problem. I personally been able to find a new carb online for under $20 since most all the US companies who make and sell small engines today have their carbs made in China.

Today I am treating my gas for all my small engines and recently have been replacing the carbs due poor running issues that have developed over the years.

[Maestro]

Originally Posted by jtodd_fl

That's sweet. Yours? What is it from? I don't think I've ever seen a car model with a "functional" engine.

http://theawesomer.com/worlds-smalle...engine/136285/

[ASBSECU E93]

OP - when using injector cleaner, it is CRITICAL to remember to only use a small amount or you will damage the internals. Most of the additives are meant for 15+ gallon tanks of fuel, so make sure you are prepared to run a full tank of fuel completely out with the additive if you go this route.

I don't think it's a fuel/air issue. I had a similar issue with a Commercial pressure washer that had sit for about 2 years, the additive solution worked fine.

[RJ_]

The extent of my small engine repair knowledge involves disassembling the intake tract as far as reasonable, followed by generous application of carb cleaner in every orifice until it runs clear, then reassemble.

Little stuff like fuel filters, fuel lines, and o-rings can all be replaced with the spare change you have in your cupholder.

Maybe you have a weak spark that's getting blown out? These usually have very simple ignitions, so maybe freshen up the electrical contacts too.

[ASBSECU E93]

Not a lot of science with these engines either. Trial and error has taught me, start with easiest or least expensive/invasive fix first, then work through more difficult/expensive repairs via process of elimination.

[Mr Tonka]

Originally Posted by jtodd_fl

That's sweet. Yours? What is it from? I don't think I've ever seen a car model with a "functional" engine.

I use it to power my ePenor.

[jtodd_fl]

Originally Posted by Mr Tonka

I use it to power my ePenor.

And just a V12 works? I woulda thought you'd need that Caddy's 16 cylinder, yo.

[Mr Tonka]

Originally Posted by jtodd_fl

And just a V12 works? I woulda thought you'd need that Caddy's 16 cylinder, yo.

What, do you think i'm Biorin or something?

[John 070]

a 16 HP lawnmower....why not hire peasants to not only fix it, but mow the lawn as well? My dad had a 17 HP Kubota, and put it this way, it was bigger than a 328i. We let the peasants deal with it...

[ASBSECU E93]

^John - HUGE difference in a 16 hp lawn tractor, and a 17 hp Kubota (Diesel) tractor....just saying