crap for carb on 10 hp Briggs (Nikki carb)

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Last time I used my Troy-Bilt (MTD) generator with a 10 HP B& S, I ran it out of gas.

Go to start it this year - no go. Took apart the Nikki carb, and what a piece of crap. I"m not impressed with plastic innards.

To make this short, even though I ran it out of gas, there was enough left in the bowl to sour, turn rancid, and stop up the plastic metering jet lowest in the bowl. Bought a bowl gasket (o-ring type and bought an extra)cleaned the jet with a needle point.

It will run, but I have these questions :
1- Gen will only run on full choke, runs fine, but concerned that when it really needs choke, there is no extra choke

2-Put Seafoam in the tank and ran it about 4 hours. Still must be on full choke. Is there any better cleaner to put in the tank & run the unit hoping it will clean whatever is still reducing the fuel mixture?

3-The bowl is too thin to drill & tap to put in a threaded plug to make a complete drain -- so what could I use to install a drain ?

4-Could I drill it, JB Weld a flared copper pipe into the inside of the bowl, and put a plug or cut-off valve on the end of the copper pipe?

So I guess the real question is would JB Weld stand up totally immersed in gas ? Bowl is thin, cast pot metal.
 
I bought a tractor years ago that ran fine. Afew weeks later flooding like crazy. Took carb apart and float was laying loose from its "arm". The solder had broken and someone JB welded the float to the arm which promptly let go from gas. So, I don't believe JB can last in constant immersion in gas. As to your choke problem, I woulkd have to believe there is something else plugged. And with today's sh!t gas and the pot metal I find that hard white corrosion is plugging up all these carbs.
 
Leave it full of gas when not in use and you will not have this problem. Nothing wrong with the gas or the carb. Just old wives tales by people that don't know what they are doing.
 
I am convinced by probably a 40 to one comment margin that it is best to run the carburetor dry. Consider though a new carb I was looking for a kit for my Husky saw when I saw that a new one was under thirty dollars.
 
The last 1/8 " of gas that was left in the carb went rancid. Turned brown, and stopped up that metering jet. I had run it out of gas, even choking it to get the last drop burned. Or, so I thought.

Took off the bowl and used carb cleaner to loosen the brown goo, and wiped out the bowl and every part that had brown or brown spots. Cleaned the metering jet with a sewing needle, so I wouldn't open it over original size.

Knew it was a fuel problem 'cause it would run on ether as long as you kept spraying.

So, maybe solder a copper pipe into the bottom of the bowl ?
 
The last 1/8 " of gas that was left in the carb went rancid. Turned brown, and stopped up that metering jet. I had run it out of gas, even choking it to get the last drop burned. Or, so I thought.

Took off the bowl and used carb cleaner to loosen the brown goo, and wiped out the bowl and every part that had brown or brown spots. Cleaned the metering jet with a sewing needle, so I wouldn't open it over original size.

Knew it was a fuel problem 'cause it would run on ether as long as you kept spraying.

So, maybe solder a copper pipe into the bottom of the bowl ?
 
Years ago Tec. Eng. had a drain that was spring loaded so you could drain the carb bowl . these were thru the thin wall metal bowls. probably would work on the plastic ones.
 
Years ago Tec. Eng. had a drain that was spring loaded so you could drain the carb bowl . these were thru the thin wall metal bowls. probably would work on the plastic ones.
 
You might put some E-85 in it and try to run it. While this might damage some fuel components, it could be that it would dissolve unwanted deposits. They do not make gasoline like they used to.
 
GASOLINE is the worst choice of fuel for a stand-by generator with a spark ignition engine. Look to converting your engine to LP fuel. Nothing to gum up. Drawback is you can not fuel the generator with a five gallon rusty bucket.

Kent
 
Do they make a reasonably priced carb conversion for B & S engines to convert them to LP gas? Sure would be handy for the generator at the farm. Use the grill tank or plumb it in solid. It's a 5000w generator. Have to look to see if it is an 8 or 12 hp engine.
 
Having grown up with a Dad that was a mechanic and been one myself since I was old enough to start helping out in the shop, I can say for sure the stories you hear are not an old wives tale. I don't know what it is about the 'new' gas but left setting it will gum up a carb just as bad as the old stuff did. Actually it often seems to do it worse because it seems to evaporate faster. In other words leaving it with the carb bowl full for very long seems to be a thing of the past unless it's a gravity fed carb. I've seen carbs done both ways and ultimately the end result is always the same.

Case in point I just spent several hours getting both a Miller and a Lincoln welder back in operational condition after setting about 6 months unused, with the bowls left full. Since the fuel has to be pumped up to the carb the bowls on both were dry and the needles were gummed up in the stuck position due to the fuel evaporating over time. Basically the fuel in the bowl kept the float up and the needle shut then gummed it up. When the fuel eventually evaporated the needle was actually stuck to the degree that it kept the float from dropping when the fuel was gon. After a minor cleaning and unsticking I finally got them both started by using my hand as a choke. For ny of you that worked on the old stuff and have seen the new stuff, you know the spring loaded pieces of crap they call chokes nowdays won't cause a high enough vacuum in the intake to pull the gas through even a partially clogged port. Once running I fed them both some fresh gas with a dose of Seafoam. I had to begin their run time with the choke partially on to keep them going but after letting them run for about 8 hours apiece, varying between WOT and idle each time I walked past them, before they eventually got back to where they'd start and run like they were supposed to.

In the past couple of years I've gone through the carbs on two different 4 wheelers that had both set with gas in them. One for about two years, the other for 6 months to year. On them the tank is above the carb and it's all gravity fed. By the time I got them there was still gas in the bowl and tanks it had gone bad. The insides of the carbs each had a nice layer of varnish all over as well as a nice layer of thick goop in the bottom of the bowl. The carb on the machine setting the shortest amount of time I was able to salvage by using a piece of stranded copper wire to clean out every port in it and replacing the needle. The one setting the longest I had to replace. Never seen it happen before but when I pulled the bowl it looked fine but I didn't get time that evening to start cleaning so it set out overnight. The next evening when I got back to it the tower housing where the float pins as well as the center tower where the jets are, for want of a better term, had both disentegrated. Again never seen it happen before in my life but it did with this carb.

Now growing up I've worked on and seen dad work on many, many carbs off of the old B/S, Kohler, Onan, etc, etc engines. I've seen them left with gas in them and seen them run dry. Typically on those the ones with gas left in them tended to gum up and need some TLC before they'd run if left too long. On the other hand the ones that had been run dry were usually not that much trouble to put back into service with some fresh fuel and a few minutes run time with the choke left partially on.

What's different nowdays when it comes to the gas and the material the carbs are being made out of I can't say, I'm not the engineer designing them. What I can say is that the gas had somehow changed and it's not for the better, and I know the material the carbs are being made of has somehow changed also. With the combination of the two you'd better not leave any engine setting very long with or without gas if you think your going to need it again anytime soon. Your best bet, if you are going to leave one sit for any length of time, is to put some Seafoam, Sta-Bil, etc in the tank. Then run it enough to get the chemical mix into the carb and you'll be a little better off come time to get it going again than if you left straight gas in it....not alot better if it sets too long, but even a little better is better than the alternative....
 
Take the bowl off and look at the main jet. It usually gets the most of the damage. You may have to take it off to clean it's passage.
Before you take the main jet out though, look on the side of the carburetor jet casting, if you see a brass looking thing, it will have a slot, and an orefice. It is part of the high speed jet system. That can be glogged.
Also, this piece has to be removed in order to get the main jet out of the carburetor casting.
Good Luck.........................Guido. :lol:
 
Can't say I never have or haven't had carb problems, but the thing that makes me wonder is this:

Every spring, I put the snowmobiles on the trailer and back em in the shed.. I don't drain gas, drain carbs.. sometimes they get stabil, sometimes not.. In 5 years I've never had a problem with carbs (I pull and clean them EVERY fall, and always look just as clean as last year) But, I do run premium gas in them.. My first sled I'd buy cheap gas, and after the engine melted down, I never did again. I wait for the day my dad's sled has a meltdown.. He bought his sled in 06, had been in storage 3 years then.. to this day has NEVER opened up his carbs, and runs the cheap garbage gas, and not much better oil.

The tractor I run on a regular basis don't bother, but seems like everything else does, but I run cheap gas in the tractors, mowers, etc..

I read on a post here somewhere that premium gas seems to have a longer shelf life.. I can't testify to it, but seems to at least to me.

Brad
 
Thanks Bill. Starting at $187+ makes it a little pricy for a part time emergency generator. Probably worth it if we go a week without power again.

Wonder how it would work to add a gas grill burner tube with the burner cut off to the intake? May have one laying around that I could experiment with on one of the mowers sitting around here. Unless someone else here beats me to it.
 
Converting to LP is fine and dandy if the engine manufacturer says it's okay to do so without making any engine changes. There are some manufacturers, (Kubota for instance), that clearly identify what fuel types are acceptable.

Here's such a decal:

Kubotadecal-1.jpg


They offer this same engine in a "gasoline only" version, (WG instead of DF), that's not equipped with a cylinder head designed to cope with dry fuels, and it's "gasoline only" suitability is noted on the decal.

However, any company selling aftermarket conversion kits isn't going to give a hoot whether or not the engine in question is really properly equipped to be run on LP....they'll sell you a kit anyway. You can look at several aftermarket kit websites and see LP conversion kits listed for the WG Kubotas, and you can look at Kubota's site and see that the WG engines are specifically listed as gasoline only.

There's no problem with using gasoline in a portable generator as long as it's stored properly.
 
If it only runs on full choke you still have a passage that's plugged up. Trying taking it apart again and looking for the blockage.

I have a Tecumseh on my log splitter that was left with the gas turned on. I tried multiple times to fix the carb, but the blocked passage must have been one that I couldn't get to. I finally gave up and spent 60 bucks on a new carb. Works great now.

I've never had a problem with carburetors gumming up as long as I shut off the gas and let the carb run dry. I suspect you had a partially blocked passage before you stored it and there was enough gas in the carb to finish the job.
 
I use Stabil for just that reason. Sea Foam is nothing more than alcohol which is why it didn't do anything. I have soaked carbs in pour in the tank injector cleaner with ok results. At this point you either need to soak in actual carb cleaner, not spray can type, or boil the carb in an old pot of water on the stove.
 

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