Here's my sharing of experience RE: servicing these B&S675 engines (vertical shaft 12000series/mine is 125K02):
As per my previous postings before: this mower worked well for 6 seasons and died on the 7th, given to me as a freebie. Owner has limited knowledge in proper upkeep of the engine.
Upon me taken possession of this said engine (a primer bulb type LMS walbro-clone side-draft), I serviced everything such as complete rebuild of carb (all B&S gasket kid), rinsing of the fuel tank, addition of a 150micron mesh filter, etc. Mower runs beautifully afterwards, no smoke no nothing.
The curiousity gotten the best of me so I bought a full head gasket kit and decided to take things apart so as to take a look at the combustion chamber, valves, cylinder walls, etc. to see how much "beating" it got during 6 season's worth of neglect:
So, this is what I saw when I cracked open the L-head:
while the deposit/overall condition is within my expectations, I figure that while I have the head off, might as well refresh the valves a bit by giving them a quick lapping job and then also checked the valve lash clearance afterwards:
(*this is the before for intake and exhaust valves*)
exhaust:
Intake:
notice how little hard deposits on the intake side of the valve?
Here are a few pics of the head part:
(before):
(after):
Torqued it down properly and then put the spark plug back into the mower and voila! fired right up.
While there are some hard-core B&S fans that would have disagree: I fond of these later B&S mowers due to the fact that with tighter emissions (their attempt to rival OHV type engines such as Honda, etc.), the result is that unlike pulsa/vacu-jet types of carb, which tends to run fairly rich/dirty which is reflective on carbon soot accumulation on spark plug electrodes and the exhaust valves, these engines (with strict emissions style LMS carb) runs very, very close to the Stoichiometric ratio (14.7 to 1)....:
Have a look at my plug (20hrs approx):
see the whitish part of the electrode? this is almost as good as a water-cooled IC automotive engine.
While I would not dispute that because of very tight emissions on these engines, sometimes it may present itself with a bit of hard starting when hot..(need a few more tugs than usual in order to get it back up running again), nevertheless: it's something that makes me decided to give up my 4hp quattro engine (see F/S section) without even thinking it twice.
Now, if only I can get some time to work on that darmed 675 easy-start that my friend ask me to work on.....
Q.
As per my previous postings before: this mower worked well for 6 seasons and died on the 7th, given to me as a freebie. Owner has limited knowledge in proper upkeep of the engine.
Upon me taken possession of this said engine (a primer bulb type LMS walbro-clone side-draft), I serviced everything such as complete rebuild of carb (all B&S gasket kid), rinsing of the fuel tank, addition of a 150micron mesh filter, etc. Mower runs beautifully afterwards, no smoke no nothing.
The curiousity gotten the best of me so I bought a full head gasket kit and decided to take things apart so as to take a look at the combustion chamber, valves, cylinder walls, etc. to see how much "beating" it got during 6 season's worth of neglect:
So, this is what I saw when I cracked open the L-head:
while the deposit/overall condition is within my expectations, I figure that while I have the head off, might as well refresh the valves a bit by giving them a quick lapping job and then also checked the valve lash clearance afterwards:
(*this is the before for intake and exhaust valves*)
exhaust:
Intake:
notice how little hard deposits on the intake side of the valve?
Here are a few pics of the head part:
(before):
(after):
Torqued it down properly and then put the spark plug back into the mower and voila! fired right up.
While there are some hard-core B&S fans that would have disagree: I fond of these later B&S mowers due to the fact that with tighter emissions (their attempt to rival OHV type engines such as Honda, etc.), the result is that unlike pulsa/vacu-jet types of carb, which tends to run fairly rich/dirty which is reflective on carbon soot accumulation on spark plug electrodes and the exhaust valves, these engines (with strict emissions style LMS carb) runs very, very close to the Stoichiometric ratio (14.7 to 1)....:
Have a look at my plug (20hrs approx):
see the whitish part of the electrode? this is almost as good as a water-cooled IC automotive engine.
While I would not dispute that because of very tight emissions on these engines, sometimes it may present itself with a bit of hard starting when hot..(need a few more tugs than usual in order to get it back up running again), nevertheless: it's something that makes me decided to give up my 4hp quattro engine (see F/S section) without even thinking it twice.
Now, if only I can get some time to work on that darmed 675 easy-start that my friend ask me to work on.....
Q.
