Small engine question.

[PedroOhare]

i was going to make this a reply in the Troybuilt thread in OT, but decided to start a new one here. I was cruising garage sales last Friday and there was a Master-,Til 3.5HP tiller for sale for $25. Since I paid $40 to rent one a couple of weeks ago ( and I have more tilling to do) I asked if it works and they said it did last season so I loaded it in My truck and brought it home. Well I can't get it to start. Well actually I can get it to start for a few seconds w ether, but then it dies. So I assume it has spark and is just not getting fuel. When I remove the air filter and spray ether (,is starting fluid still ether?) ,everything looks very clean, and the choke mechanism and throttle work fine. It is a B&S 91200 series engine and does not have a primer pump. The chamber is dry once the ether stalks off.

So I ordered a carb rebuild kit ($20 a shipping) but it won't get here for a week. Does anyone have any ideas to try in the meantime? I guess I could take the carb apart and clean everything but if I do that I will wait till the parts get here rather than Jack around. Would blowing compressed air into the carb potentiality clear a plug and get it going?

I am all ears.

Pedro

[Roly]

i was going to make this a reply in the Troybuilt thread in OT, but decided to start a new one here. I was cruising garage sales last Friday and there was a Master-,Til 3.5HP tiller for sale for $25. Since I paid $40 to rent one a couple of weeks ago ( and I have more tilling to do) I asked if it works and they said it did last season so I loaded it in My truck and brought it home. Well I can't get it to start. Well actually I can get it to start for a few seconds w ether, but then it dies. So I assume it has spark and is just not getting fuel. When I remove the air filter and spray ether (,is starting fluid still ether?) ,everything looks very clean, and the choke mechanism and throttle work fine. It is a B&S 91200 series engine and does not have a primer pump. The chamber is dry once the ether stalks off.

So I ordered a carb rebuild kit ($20 a shipping) but it won't get here for a week. Does anyone have any ideas to try in the meantime? I guess I could take the carb apart and clean everything but if I do that I will wait till the parts get here rather than Jack around. Would blowing compressed air into the carb potentiality clear a plug and get it going?

I am all ears.

Pedro

See if you are getting fuel in the float bowl.  If no fuel check the needle valve, if fuel is there you will need to clear the passages and jets.  Roly

[K. L. McReynolds]

You can try the carb kit. If you get lucky---and you soak the carb pieces in carb cleaner and blow the pieces dry with a nozzle---and you get lucky, it might work.

If not, buy a complete carb and new spark plug. And check the oil level and wiring on the shut off/safety switches.

I spent over 40 years rebuilding carbs---and small engine types were the worst. I was a factory trained/certified Husqvarna repairman. I had all kinds of tools/equipment(except for a test bench for carbs) and probably only was successful 30% of the time in rebuilding carbs. Was cheaper(time/labor) to replace the carb.

[daddo]

I suggest you run it before you buy it. You may have got it for 5 bucks.  


 No disrespect to them, but if I can't run the engine, I'm assuming the engine is no good. I don't fall for the; "All it needs is a carburetor" trick.

 Flush the tank and fuel lines, sharpen blade, replace the carb, fuel filter (or install one), air filter, plug and oil and it should run.

[tomsteve]

drain and clean the gas tank. refill. have a bottle of gas to pour a bit down the carb throat. start it. use hand as choke over carb if possible to keep running. if not  use bottle to dump some gas down carb to keep running. tap on side of carb with screwdriver handle. 
report back.

[splinter7612]

Try this tip I got from a friend of mine who owned a lawn mower shop, remove the bolt from the bottom of the carb bowl and blow out the little holes with compressed air in that bolt, I did that in my lawn mower which has a Briggs engine and it started, but when it was necessary to to do this on a regular basis I ordered a new carb on Amazon for $12 and now it starts on the first pull and has never run better.

[fredhargis]

Nothing to add, except that with today's gas if some sit in the fuel system for any length of time it might cause a starting problem. One other thing, I've been told multiple times by some good small engine mechanics not to use ether on these small engines. It can (apparently) cause more damage.

[pprobus]

i was going to make this a reply in the Troybuilt thread in OT, but decided to start a new one here. I was cruising garage sales last Friday and there was a Master-,Til 3.5HP tiller for sale for $25. Since I paid $40 to rent one a couple of weeks ago ( and I have more tilling to do) I asked if it works and they said it did last season so I loaded it in My truck and brought it home. Well I can't get it to start. Well actually I can get it to start for a few seconds w ether, but then it dies. So I assume it has spark and is just not getting fuel. When I remove the air filter and spray ether (,is starting fluid still ether?) ,everything looks very clean, and the choke mechanism and throttle work fine. It is a B&S 91200 series engine and does not have a primer pump. The chamber is dry once the ether stalks off.

So I ordered a carb rebuild kit ($20 a shipping) but it won't get here for a week. Does anyone have any ideas to try in the meantime? I guess I could take the carb apart and clean everything but if I do that I will wait till the parts get here rather than Jack around. Would blowing compressed air into the carb potentiality clear a plug and get it going?

I am all ears.

Pedro

Pedro,

Not a professional mechanic, just an experienced amateur, but 99% of the issues I have run into regarding small engines boils down to a dirty carb.  What you are describing is a classic case, assuming the gas is able to get to the carb.  As others have suggested, check the fuel line, the easiest way and the quickest, if there are no obstructions, is to pull it off at the carb and see if fuel freely runs out (into a container you have, of course).  If not, then go to the tank, pull the hose off of the tank, ensure you get good flow from the tank, trash in the tank may have plugged up the hole.  If you get good flow there, there the problem somewhere in the line, check to see if there's an inline filter, shutoff valve, etc. and either replace (the filter) or check and replace if needed (the valve), if those are OK and still no flow through the hose, then replace the hose, it is possible for trash to clog the hose, although the only time I have experience this was due to a steel gas tank that had sat with gas in it for years and the tank was very rusted.  If you get good fuel flow at the carb, the problem rests solely in the carb and you need to tear it down to clean it.  No getting around it.  I also have had no issues with re-using the old gaskets (in some cases, I had small engine powered tools that where the company was out of business and no idea where to get replacement gaskets) although you could go to the local auto parts store and get gasket sealant and apply that  while re-assembling for peace of mind.  Since you already have a rebuild kit on the way, which should include new gaskets, you really have nothing to lose, other than time, to tear down the carb, clean it, put it back together and try it and potentially having to do it again to put on the new gaskets.    Just be sure to check the settings of the mixture screws.  Turn them in and count the number of turns it takes, to the nearest 1/4 or 1/8 turn should get you close enough to allow the engine to run when the screws are re-set.  If you forget, a rough rule of thumb that has worked surprisingly well for me is 1-1/2 turns from fully closed, it is the recommendation used by Briggs and Stratton and I have used it on equipment (both B&S and non-B&S) that I did not have a manual for (both two stroke and four stroke) and has so far worked for every small engine I have tried it.  Keep in mind that it only gets it close enough to run stable enough to make fine tuning adjustments.  One thing, DO NOT over-tighten setting screws, just until they stop.

Good luck,
Paul

[crokett™]

It's a carb problem. Clean the carb or get a new one. I quit rebuilding carbs when I learned I could get a new one for the price of the rebuild kit. The carbs that I've cleaned I've never had it not work to soak it in carb dip for an hour, rinse it, then take a compressor and blow off all the water and blow out the jets.

[CLETUS]

This sounds like a stuck needle valve. It will run until the bowl is dry. Then as is sits, some fuel will slowly leak into the bowl. Boom it will start and run until its dry. Here is a trick you can use to limp it along.

Take the screw out of the bottom of the bowl. Tap the side of the bowl with the handle of a screw driver. If fuel starts flowing you know you just unstuck the needle valve. Usually, it will stay unstuck for a while. If you're using it and it shuts down again, just rapp the bowl with the screwdriver, wait 30 seconds and start it up.

An old farmer taught me that trick, it's served me well. I still haven't rebuilt the carb in my 1951 Allis Chalmers, once a year I have to tap on the carb.