One hit, then nothing

[theoldwizard1]

First, this is not my "first rodeo" ! I have been "messing" with small engines for almost 50 years. Since retiring 10 years ago, it is one of my favorite hobbies, although I don't go "looking for work".

I have a Craftsman counter rotating rear tine tiller with a B&S industrial engine. The neighbor ran the tank dry and now even with fresh gas, it will only hit one time and that is it. I have had the carb off and done the best job cleaning it that you can without a heated ultrasonic cleaner. I have used a tiny wire to clean all of the passages and they all flow fluid.

Clean fuel is flowing from the tank, through the needle and seat.

What am I missing.

 

[Rivets]

Sure would be nice if you would have posted the model,type and code numbers of your engine so we can see which of the hundred Briggs engine you are working on.

 

[theoldwizard1]

133402 0083 01 95061607
Do you really think it matters ? This is clearly a fuel problem and every B&S carb I have seen for the past 20 years, regardless what single cylinder engine it cam off of, is almost identical.

 

[Rivets]

Do I really think it matters, well yes. This is not my “ first rodeo” either. I’ve be working on small engines for 50+ years, plus taught repair for almost 35 years and when diagnosing fuel problems you must know which carb you are dealing with. Briggs uses 6 different carbs on their engines, updraft, downdraft, VacuJet, PulsaJet, Pulsa-Prime, and FlowJet, with variations in which one. Knowing which one is on your engine makes it easier to diagnose the problem. Do l really think it matters, well no it doesn’t to me. Your reply told me that what ever I told you would have been wrong and you know more than 99% of the members of this forum. For that reason I’m getting out of this thread, but will be watching for the member who has ESP to know what you have and the answers you want. Gook Luck, though you probably won’t need it with your experience.

 

[theoldwizard1]

The saga continues ...

There is a block off plate where the low oil level sensor would be installed.

Using a spark tester, I have validated that one pull of the starter cord produces multiple sparks through the entire pull.

The plugs comes out wet after a couple of pulls. I have validated that the needle, seat and float are doing their job and sealing the carburetor bowl when it is full. It is acting like it is very rich mixture.

The replacement carburetor is a B&S 495652, but I have not located one.

 

[cpurvis]

Does it do this on a repeated basis? By that I mean it hits once and you try again an hour or a day later and it does the same thing?

Get another spark plug and swap it out when it does the 'one and done' thing.

 

[theoldwizard1]

Flywheel key is fine. Oil level is fine.
New spark plug on order.

 

[theoldwizard1]

Oil level - check
Flywheel key - check
New spark plug - BINGO !

If it had not tried to start, I would have swapped the plug earlier, but I did not have any in my stock.

This is the first time in over 20 years that I have "fixed" a single cylinder engine by changing the spark plug !

 

[bertsmobile1]

Due to EPA regulations for 0.0000000% lead in exhausts the insulator on the nose of a spark plug is no longer glazed.
Because of this stuff sets stuck on the rough surface
Modern fuel. which s not petrol conducts electricity at cylinder compression pressures so a slightly damp plug will not spark.
This is what causes the infamous "bad out of the box" syndrome that ignorant morons slather all over social media .
Usually if you put it into a very hot engine it will come good again when it burns the deposits off
A bit hard with a single cylinder pull start engine.
Some times it happens with a single misfire & some times not.
This is dependent upon the actual composition of the fuel being used at the time
And that varies wildly from a 50:50 mix of benzene & tolunene to actual petrol