Hi Shane -
No solution yet. Turned out the flywheel worked perfect on neighbour's machine same type.
But the reason for the odd timing was that the flywheel key kept shearing, because of back kicking.
Now the timing and ignition bits are ok and tested. But engine still black smokes and 8strokes (misses every second work stroke).
I'm in the process of analysing what's going on in the intake & carb, as it clearly seems the engine takes in too much fuel.
It's a dead simple system with a float valve gravity feeded carb, but it does not flood while running, or when stopped.
Need to do my BX, but ... A CLUE !!!
Moderator: RichardW
Is this one of the B and S engines with the carburettor sitting on top of the fuel tank? I don't suppose it is as I should imagine for a tractor its vertical and the carburrettor is fed by gravity from a tank above the carburrettor.
I've never understood how the fuel is drawn up from the lower tank and if you have this system wonder if it could cause your overfuelling.
jeremy
I've never understood how the fuel is drawn up from the lower tank and if you have this system wonder if it could cause your overfuelling.
jeremy
Hi Jeremy [;)]
You may have noticed I've been a bit off-list for a while, as the strugglig with this ole Briggs gent is quite exhausting ...
It's a side valve engine vertical axle, horizontal piston, and carb sidemounted on engine, gravity fed off the tank, fitted rather high and functioning as the "dash panel" under the steering wheel.
I left ole Briggs a couple of days, giving both of us a chance to think it over ...
Now I'm sure the ignition issues was completely OFF track ...
Removing the filter cartridge and looking down the filter carrier, I noticed excess fuel building up here while engine running. Only while running, the carb is NOT flooding when engine is stopped (float valve/level issue). The float is exactly horizontal to carb body as pr spec when upside down to close float valve by gravity.
As the engine black smokes and 8strokes, it made me try this evening removing the filter carrier, leaving the carb intake freely open.
SURE [8D] - NOW the engine runs just GREAT [:D] !
- as the excess fuel now simply drips down from carb intake, leaving a sensible gas mixture admitted to engine [:o)]
OK - right ! the carb is defo overriching the engine then [8)]
But why ?
Countless times the carb has been removed, disassembled, blown thru, and all jets removed and blown thru, and tried for no overtorquing. Seals has been tested etc. etc. etc.
Then I remembered from last re-assembly, that the main nozzle jet always had a strange feeling like it had too much clearance in it's securing threads.
This makes me wonder if fuel in fact bypases the jet, adding to overrich the engine.
The nozzle has no means of sealing, other than tensioning when fitted ...
So off we go with the nozzle - I thought [8D]
- and by laws of Murphy, the nozzle now won't budge [B)][xx(][:(!]
- end of day 153 fiddling with ole Briggs gent [B)]
[:D][:D][:D][:D][:D]
You may have noticed I've been a bit off-list for a while, as the strugglig with this ole Briggs gent is quite exhausting ...
It's a side valve engine vertical axle, horizontal piston, and carb sidemounted on engine, gravity fed off the tank, fitted rather high and functioning as the "dash panel" under the steering wheel.
I left ole Briggs a couple of days, giving both of us a chance to think it over ...
Now I'm sure the ignition issues was completely OFF track ...
Removing the filter cartridge and looking down the filter carrier, I noticed excess fuel building up here while engine running. Only while running, the carb is NOT flooding when engine is stopped (float valve/level issue). The float is exactly horizontal to carb body as pr spec when upside down to close float valve by gravity.
As the engine black smokes and 8strokes, it made me try this evening removing the filter carrier, leaving the carb intake freely open.
SURE [8D] - NOW the engine runs just GREAT [:D] !
- as the excess fuel now simply drips down from carb intake, leaving a sensible gas mixture admitted to engine [:o)]
OK - right ! the carb is defo overriching the engine then [8)]
But why ?
Countless times the carb has been removed, disassembled, blown thru, and all jets removed and blown thru, and tried for no overtorquing. Seals has been tested etc. etc. etc.
Then I remembered from last re-assembly, that the main nozzle jet always had a strange feeling like it had too much clearance in it's securing threads.
This makes me wonder if fuel in fact bypases the jet, adding to overrich the engine.
The nozzle has no means of sealing, other than tensioning when fitted ...
So off we go with the nozzle - I thought [8D]
- and by laws of Murphy, the nozzle now won't budge [B)][xx(][:(!]
- end of day 153 fiddling with ole Briggs gent [B)]
[:D][:D][:D][:D][:D]
I suppose its a tribut to briggs and stratton that although I've had limited contact with their engines over about 35 years I have never really done any work on them.
I do recall on one having to play around with the air filter and finding that the screw holding the air cleaner on had to be replaced for the engine to start as it passed through the choke flap and with a hole in the middle of this flap it wouldn't work!
yes - fuel creeping round a jet could cause the problem. I suppose if you can't get it out you could always paint a little polyester resin or other petrol proof substance round it to seal. After all you get to a stage where you think you haven't much to loose.
usual problem from a frequently dismantled carb is air leaks and lack of fuel!
Will day 154 be successful?
jeremy
I do recall on one having to play around with the air filter and finding that the screw holding the air cleaner on had to be replaced for the engine to start as it passed through the choke flap and with a hole in the middle of this flap it wouldn't work!
yes - fuel creeping round a jet could cause the problem. I suppose if you can't get it out you could always paint a little polyester resin or other petrol proof substance round it to seal. After all you get to a stage where you think you haven't much to loose.
usual problem from a frequently dismantled carb is air leaks and lack of fuel!
Will day 154 be successful?
jeremy
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