Small engine troubleshooting

[Don Y]

A friend is having trouble with a small (5-7HP) engine. Not starting. Aside from checking for spark (after ensuring no "old" fuel present), I can't think of any easy tests that he can perform...?

[gfretwell]

Squirt a little gas right into the carb throat and see if it runs a few seconds

[notbob]

Squirt a little gas directly into the spark plug hole (spark plug removed). Put plug back in and then try and restart it. This will tell you if you have a problem with the carburator. .

nb

[Stormin Mormon]

Remove spark plug, and clean it. Check for "wet" with gasoline.

Does it start with a spray of ether onto the air cleaner?

Is the oil filled up to the full line on the dip stick?

[Ralph Mowery]

I ran into both of those on 2 seperate samll engines.

On one the gas shut off was backwards from what I am used to seeing , when cross ways to the line it was on instead of off. Took about 20 minuits to find that as I kept turning it off and on and the tiller it was on would run for about 30 to 60 seconds.

The other was a 5 KW generator. It had an on/off switch that was not mentioned in the manual. As it was dark the first time I tried to start it, I missed it and about an hour later the power came back on. Found it the next day in the sun light.

[Don Y]

I wouldn't trust him to do this. If I knew he had a can of "hot shot", I might suggest it (as that is somewhat self-limiting in terms of quantity).

Pulling a plug wire and watching for a spark is relatively easy to "get right"...

[clare]

Just don't sqirt the gas in while it is cranking over. I used to have an old gasoline blowtorch I used to squirt gas into intakes - if it backfired I turned off the valve and there was no chance of the fire coming back up into the "squirter"

I got my first teaching gig when an instructor poured gas down the carb of a chevy six in the auto shop and it backfired. He got pretty badly burned - was off work for 9 months and was still pretty tender when he returned the following september.

[clare]

A business card works pretty well to adjust the mag clearance.

[Eagle]

Don Y explained on 1/12/2016 :

Heat up the spark plug and try starting it.

[Stormin Mormon]

I've never heard that one. What does that do? Heat it, how? Pot of boiling water on the stove?

[Mr. Emann]

If it's an overhead valve engine check to be sure the valves are opening. Sometimes the adjustment backs off, and sometimes the tip of the push rods will wear down or break.

[Eagle]

Getting the plug up to temp will evaperate gasoline quicker and start a cold engine faster. I do this with My mower [as well as shoot a little gas into the plug hole] and 9 times out of ten it fires right up.

Yes, and don't forget the carrots and onions.

[clare]

Not ALL business cards are the same thickness, but a atandard business card stock is "12 pt" or "100 lb" stock - and 12 point means the paper is 0.012" thick.

That just happens to be "close enough" for most Briggs engines - with specs ranging from .006-.010 on the lowest, to 10-14 on the highest, with most spec'd at .008 - .012, and a few at .012 - .020.

[clare]

Take the plug and heat it with a propane or butane torch. This drives out any moisture, evaporates any fuel, and removes any oil fouling. - making the plug more likely to fire if adequate fuel and spark are available,

Works good for starting flooded engines. I've also on occaision held the torch over the plug hole and pulled the rope. It sucks the flame into the cyl and very quicly clears a flooded cyl.. Just stand back, because it can blow a bright blue flame a few inches out of the hole too.

[clare]

The heat range has NOTHING to do with starting temperature. A hotter range plug won't start any easier than a cold one (at least not the first time). A cold plug may foul quicker -- but that's a different subject.

[Wade Garrett]

How do you handle the resulting fire or explosion?

[Ralph Mowery]

What has the heat range got to do with the engine starting if it is clean and not caked up with carbon or some such ? If the plug is clean the heat range does not come into play as far as the engine starting.

[Stormin Mormon]

There once was a man from Morass, who cleared with a torch of brass.

I leave it to gentle readers to write the rest of the limerick.

I've cleared flooded by remove the spark plug and then yank the start cord several times. No blue flames for me.

[Eagle]

[e-mail] formulated on Wednesday :

Yep.

[clare]

It is just a short "whoosh" and it's done..