B&S 10A912-2266B1 starts but...

M

MD Fields

Forum Newbie
Joined
Jun 24, 2019
Threads
1
Messages
2
Here is my noodle scratcher: I acquired a pressure washer with a B&S Quattro 4hp engine. It even starts on the first pull (yay me!) BUT, it will only start if the boot is pulled from the spark plug yet still close enough to arc. The engine runs a little rough but stays running. When I try to reconnect the boot it immediately stalls. Thought of wrong plug installed or wrong gap. My life has been a Jack of all trades although my small engine repair abilities are lacking. I welcome any attempts to enlighten me as to why this problem exists and especially how to solve it
 
Last edited:
M

MowLife

Well-Known Member
Joined
Oct 18, 2018
Threads
3
Messages
365
Possibly the boot has a crack and shorting out to the block when on the plug?
 
B

bertsmobile1

Lawn Royalty
Joined
Nov 29, 2014
Threads
64
Messages
24,705
A plug that is fouled will allow the spark to travel down the sides rather than jump the gap & ignite the fuel.
The lazy way to check for fouled plugs used to be to pull the cap off and hold it 1/2" to 1/4" off then end of the plug.
If the engine changed speeds, that plug is bad.
The old engine analysers you used tom see in garages with plugs & wires every where did exactly this , electronically.

Now days the Engine management system does the same thing.

Back in the 60's to 90's you might remember all of those Spark Intensifiers & Power Increasers and other "miracle power increasers "
All of them , apart from being snake oil which caused premature failure of coils & condensers, were nothing more than a gap in the spark plug wire.
Back in the 10's through to the 50's the bodge was to get a biro tube , cut the HT wire(s) and shove each end into the tube with a gap between them.
Then there was a hose with a fireman's brass button on each end of the wire, all sorts of cures & improvers.
 
M

MD Fields

Forum Newbie
Joined
Jun 24, 2019
Threads
1
Messages
2
bertsmobile1 said:
A plug that is fouled will allow the spark to travel down the sides rather than jump the gap & ignite the fuel.
The lazy way to check for fouled plugs used to be to pull the cap off and hold it 1/2" to 1/4" off then end of the plug.
If the engine changed speeds, that plug is bad.
The old engine analysers you used tom see in garages with plugs & wires every where did exactly this , electronically.

Now days the Engine management system does the same thing.

Back in the 60's to 90's you might remember all of those Spark Intensifiers & Power Increasers and other "miracle power increasers "
All of them , apart from being snake oil which caused premature failure of coils & condensers, were nothing more than a gap in the spark plug wire.
Back in the 10's through to the 50's the bodge was to get a biro tube , cut the HT wire(s) and shove each end into the tube with a gap between them.
Then there was a hose with a fireman's brass button on each end of the wire, all sorts of cures & improvers.
Click to expand...

MD Fields: Hard to find the exact plug for a replacement so cleaned and regapped old plug. Also cleaned very rusted magnet/coil, also regapped, which seemed to solve the original problem. Can now run with boot connected. Now found a good carburetor cleaning is in order so wish me luck
 
B

bertsmobile1

Lawn Royalty
Joined
Nov 29, 2014
Threads
64
Messages
24,705
MD Fields said:
MD Fields: Hard to find the exact plug for a replacement so cleaned and regapped old plug. Also cleaned very rusted magnet/coil, also regapped, which seemed to solve the original problem. Can now run with boot connected. Now found a good carburetor cleaning is in order so wish me luck
Click to expand...

Hard to find ? Really ?

Just bout every petrol station, hardwear shop mower shop, car parts shop will keep the plug you seek
Champ RJ19LM , Ngk BR2LM , Bosch WR11EO plus a million house brands.
 
You must log in or register to reply here.

Footer Links 1

Top