[Lonestar Guy]

I have a Troy Built 5500W generator with a 4500 series B&S engine. It's several years old, but since it's only used when power is out for extended periods, it has less than 100 hours of run time. (once power was out for 2-3 days due to ice storm)

I got it out last summer during a power failure but it wouldn't start. It did however turn over but only briefly before shutting down. I could not get it to stay on, no matter where I adjusted the choke and kept pulling the rope. If I remember correctly, it would only turn over when not at the choke setting, but not sure. It's possible the gas may have been old. I'm not sure if I put fresh gas in at that time. OK, so that's a while ago.

I need to get it running of course, so I am back at it. Stupidly, I tried starting it with the old gas still in there. Don't ask me why. It wouldn't even turn over at all. Anyway, I drained it all and added fresh gas, at least a gallon and it is flowing down the tube to the carburetor. It still wouldn't turn over no matter where I adjusted the choke/run lever.

I then gapped and installed a new plug. The old one was blacked but I never checked it for spark. It still didn't turn over. I then checked the new plug for, and found spark with the plug external to the engine and reinstalled it. I will say, the plug wire has a very small chunk of the outer insulation missing. I'm aware if close enough to ground it could leak 'spark', so I wrapped it with electrical and friction tape.

I removed the (oddly enough) very clean air filter and saw that the intake flapper (choke/run) valve was functioning properly and it was all quite clean.

After viewing a YouTube video on carburetor repair, I removed the carburetor. Aside from 3-4 pin-point sized black specs, it appeared clean. I blew all the components out with compressed air and reassembled it. The engine would still not turn over although there was at one moment the briefest (very brief) sputter. But only once!

I borrowed a compression gauge set from local auto parts store and checked the compression last night. It came up to 60 psi after 5 pulls and only dropped a few psi over night.

At this point, I'm perplexed. The only thing I can think of is perhaps I'm flooding it or the air to fuel mixture is not correct or else the spark is not what it should be.

Is there something more I can do to check the integrity of the spark?
Should I remove the plug from the bottom of the carburetor and drain it and then try to crank it on Run instead of Choke?
Could it be the plug wire degrading the spark?

Any ideas would be helpful. Thanks!

 

[hkstroud]

There is a good possibility that you let it sit for an extended period of time with gasoline that was 10% ethanol. That will gum up the jets of the carburetor. Everything you related indicates that.
You can remove the carburetor, dissemble and clean the jets. Or you can simple replace the carburetor which is what I would recommend. They are relatively cheap and easy to obtain.
Always let small engines run dry of gasoline if they are going to be stored for a perios of time. There is a gasoline additive that can be added but I prefer letting them simply run dry of gasoline.

 

[Lonestar Guy]

There is a good possibility that you let it sit for an extended period of time with gasoline that was 10% ethanol. That will gum up the jets of the carburetor. Everything you related indicates that.
You can remove the carburetor, dissemble and clean the jets. Or you can simple replace the carburetor which is what I would recommend. They are relatively cheap and easy to obtain.
Always let small engines run dry of gasoline if they are going to be stored for a period of time. There is a gasoline additive that can be added but I prefer letting them simply run dry of gasoline.

Thanks! I guess I don't know the internal parts of the carburetor that well. I would like to know what the 'jets' look like. There is a cylindrical tube with small holes in it. They were all clear. As well, the float seemed to be working but all I could see was one tiny hole as the side that appears to be 'plugged' by a piece of rubber when the float is in the up position. I haven't tried to start it today since compression testing it... busy with grandson duty. Will try soon though but probably avoid choking it at first.

 

[SeniorSitizen]

If you haven't, check oil level.

I've learned over the years when an engine has set for a length of time to leave my hand off of the choke which can flood the combustion chamber very easily without being aware of it. I'd rather put about a 1/4 teaspoon of gas directly into the air intake of the carburetor to determine if it will fire then go from there. The engine has a better chance of doing the 14/1 air fuel ratio with the 1/4 tsp or less.

 

[Calson]

The aerosol cans with auto engine starter mixture can work on small engines as well. If a jet is gummed off then the gasoline is not aerolized and will not burn. Gasoline is flammable only as a vapor.

Either put in a fuel stabilzer and run the generator 10 minutes each month or run it until the tank is empty to avoid future problems. I have my standby generator run for 10 minutes every other week. With my pressure washer I run the engine until it is out of gas.

 

[Lonestar Guy]

If you haven't, check oil level.

I've learned over the years when an engine has set for a length of time to leave my hand off of the choke which can flood the combustion chamber very easily without being aware of it. I'd rather put about a 1/4 teaspoon of gas directly into the air intake of the carburetor to determine if it will fire then go from there. The engine has a better chance of doing the 14/1 air fuel ratio with the 1/4 tsp or less.

Oil level is good, especially since I added some which I forgot to note, but I don't think this engine has a sensor anyway. Or I should say, I don't see a sensor or indicator anywhere but I haven't had ALL the covers off. Someone might tell me that low oil can be an issue even without a sensor.

 

[Lonestar Guy]

OK, now that I think about the carburetor and after looking at some photos online, it's possible that the atomizer/jet (?) might be clogged. So there is a tube (main tube?) that fits down into the tube with the holes (previously mentioned). At the end of one of them is what appeared to me to be a rubbery seal (black) but must be the jet(?). It did not appear to have a hole through it, but I thought it was just a seal so didn't want to poke a hole in it. Kinda looks 'dirty'. I'm just guessing here. Does that sound like the jet and sound as though it's clogged?

 

[hkstroud]

https://www.ebay.com/i/233373622254...MI34Ddo6626AIVjozICh3WhAEnEAQYAyABEgIX9_D_BwE

 

[SeniorSitizen]

The reason I mentioned the oil is because of a leaking carb needle valve can put all the gas in the crankcase.


By putting a 1/4 tsp of gas in the air intake that tells us 3 things that just wearing ourselves out pulling a rope doesn't tell. 1) if it fires and tries to run we have fire at 2) approx. the correct time and 3) compression. Now go to work on the carburetor.

 

[Lonestar Guy]

The reason I mentioned the oil is because of a leaking carb needle valve can put all the gas in the crankcase.


By putting a 1/4 tsp of gas in the air intake that tells us 3 things that just wearing ourselves out pulling a rope doesn't tell. 1) if it fires and tries to run we have fire at 2) approx. the correct time and 3) compression. Now go to work on the carburetor.

OK, thanks SeniorSitizen! I finally had to the time to do this and yes, the squirt of gas into the air intake did cause the engine to turn over, albeit briefly! So, apparently, since gas does flow from the feed tube, I have a carburetor issue. To be clear, there was gas in the carburetor (I removed it), probably in the bowl, but apparently is not getting to the intake.

As you may have been confused by my description above about the tube with holes and the seal and all that, it was from memory and not very accurate. lain: Yes, there is a tube with holes in it that the float slides up onto and it appears that what I thought was a seal in the bottom of the float 'column', now appears to be an occlusion (based on photos of new floats). See image. I'm assuming that gas from the bowl is supposed to be sucked up through this column?

I'm fine with getting a new carburetor if needed but after I hear a response on what I found, I will attempt to clean the blockage (if I'm correct on that).

Thanks again for the input and for allowing me to the space to learn. I've always feared this kind of thing so this is a big step for me. I feel much closer to a resolution.

 

[surferdude2]

It sounds like the main jet is plugged. That looks like it in the middle of that shot you posted. It's that brass part you see there... it's supposed to have a hole in the center of it. You can remove it with a flat blade screwdriver (you'll first have to pull that pin and remove the float) or try to clean it in place . Spray some cleaner on it and run a small wire through it or use a toothpick. Be careful not to enlarge it. If/when removing the float, be careful to not lose the float valve... it'll be attached to the float my a wire clip... notice how it's put together so you can get it back the same way. Don't let it scare you... it's easy enough.

You are correct, the venturi vacuum created by the air flow through the carburetor pulls gas through that jet and up that column and into the air stream.

That'll probably get it going and if you're lucky the rest of it will clean up if you run a tank of gas laced with injector cleaner in it.

 

[Lonestar Guy]

It sounds like the main jet is plugged. That looks like it in the middle of that shot you posted. It's that brass part you see there... it's supposed to have a hole in the center of it. You can remove it with a flat blade screwdriver (you'll first have to pull that pin and remove the float) or try to clean it in place . Spray some cleaner on it and run a small wire through it or use a toothpick. Be careful not to enlarge it.

You are correct, the venturi vacuum created by the air flow through the carburetor pulls gas through that jet and up that column and into the air stream.

That'll probably get it going and if you're lucky the rest of it will clean up if you run a tank of gas laced with injector cleaner in it.

Alrighty, it's done! Took 15 seconds. I used a tiny drill bit, gently of course, and cleared the gunk at both sides. It wasn't small enough to enter the hole but the gunk was not inside the hole, if that makes sense. Can now see thru the hole! Unfortunately, in the process of putting the carb back together the first time, I slightly damaged an o-ring. It might be OK for now, although I'm not the type of person to leave something like this for long. I will likely get a rebuild kit if I can't easily find a single o-ring somewhere.

Thanks again all contributors! I've learned a lot. I suppose I will report back later when it's fully operational.

 

[surferdude2]

You may be surprised when you see what a rebuild kit costs relative to the price of a new carb.. I've seen the kit cost more!

That motor ought to start now.

Tip: If it dies when you try to idle it down, there is another jet/passage way that's responsible for that... (up on top somewhere usually) it'll likely clean itself if you run a tank of gas with cleaner in it or might clean up in time anyway.

 

[Lonestar Guy]

You may be surprised when you see what a rebuild kit costs relative to the price of a new carb.. I've seen the kit cost more!

That motor ought to start now.

Oh yes... I'm discovering all that. The cost is not significant in any case but yea, it may end up being a new carb. Too bad. I just need a 5 cent o ring. :smile: I'll look around. I've got time.

 

[Dave Sal]

I had a similar issue last year (or maybe the year before) when I tried to start my lawn mower for the first time of the season. It is a Craftsman mower with a Honda engine. I always run it dry in the fall but there must have been a small amount of gas left in the carb. I checked for spark and that was fine. I pulled and pulled on the starter cord until my arm was about to fall off. Then I thought I'd pull the air cleaner off and spray some starter fluid directly into the carb. First pull and it started right up, but died after the carb cleaner was burned off. I could actually keep it running by spraying carb cleaner in there every few seconds. I think I came on here asking for recommendations and was advised to pick up some "Mechanic in a Bottle", which I did. Bought fresh gas, added the recommended amount of Mechanic in a Bottle to the gas tank, and had to spray the starter fluid again to get it to start. It started coughing and I had to keep it alive with the starter fluid, but it eventually smoothed out. The mower had a tendency to surge at all times and that slowly started improving over the summer. I add some to every tank of gas. The Mechanic in a Bottle is good stuff, and will clean out the fuel lines and the carburetor over time.

I think I'll fire up my generator once it warms up outside. Probably going to have a similar experience as OP as well.

 

[ron45]

Did you make sure the pet cock was turned to the on position.?

 

[Fix'n it]

i'm here looking for info. my auger would not start today, its been sitting a while. it runs on ether . i took the carb off and cleaned, it looked like new inside. still only runs on ether.
so, it looks like if it doesn't run in the morning i will just replace it . thats to bad, it only have about 40 holes in it. :-(
first time i have ever have this problem.

 

[lenaitch]

Seeing as something like a generator is only needed when it's dark or stormy, proper storage and regular testing is important. Many of us have different routines, but I change my fuel (with Seaform) twice and year and run the generator under load. When I'm done, I shut off the fuel and let it run dry, then set the choke and try to re-start it to pull as much fuel as I can out of the carb. I also leave it stored with the choke closed to keep tiny critters from calling the carb home.

 

[RockyMtBeerMan]

Don't leave gas in fuel tank over the winter; tends to gum up.

If you have to, ad Stabil to the gas to prevent it from doing that.

 

[Dave Sal]

i'm here looking for info. my auger would not start today, its been sitting a while. it runs on ether . i took the carb off and cleaned, it looked like new inside. still only runs on ether.
so, it looks like if it doesn't run in the morning i will just replace it . thats to bad, it only have about 40 holes in it. :-(
first time i have ever have this problem.

If you mean it will only start with starting fluid, then your fuel lines are probably gunked up. I had a really really hard time starting my lawn mower last year and about tore my right arm out of the socket from pulling the starter cord so many times. I bought some Mechanic in a Bottle and mixed it in with the gas and let it sit for a day or so, then went back and sprayed the carb with starting fluid and it fired up, sputtering and spewing smoke for a bit but then it evened out. Today was the first time I tried to start it for the season and sprayed the starter fluid as usual and it fired up on the first pull.