I have a Murray with an opposed twin cylinder Briggs. It runs pretty good but when I get in tall grass it does not idle up. I mow at full throttle but it is like the governor never kicks in. I have adjusted the gov but still same result. What could I be looking for?
#2
reddragon
if it runs fine out of tall grass...then youre in too deep!:laughing:........the mowers are designed to mow the tops of grass off........how deep is your tall grass?
Your problem might be you are mowing to fast and it can't handle grass that thick and tall.Are your blades sharp so it don't pull the engine down from dull blades.And maybe you need to raise the deck up a notch,because you are mowing to close to the ground and your mower can't handle mowing that much at once.If you want a shorter lawn you may have to mow it two times the second time shorter. Things to try good luck:licking:
Thanks for the reply but I am mowing very slow and not short I have it on number 3. My mower actually doesn't go that fast anyway. The governor does not govern the engine up as it should at all. Just wondering if there is anything else to look at before I check the governor internally.
#6
reddragon
the governor will set your speed [rpm] ...if the tall grass is bogging you down...its other factors like carb or bad blades or other resistance factors....are you saying its not at speed all the time??
Your engine should Idle around 1000 RPM, and run around 3600 RPM at full throttle... The governor is only going to attempt to hold the RPM setting you have chosen, if you are mowing at less than full throttle, that is what it will attempt to hold...
If you are at full throttle, it will hold that until it gets overloaded... You can reduce the overload by slowing down the forward speed, OR raising the deck, so it has less to cut...
If you are finding that you can not mow your grass as fast & as short as it once cut... You have something using up the power, OR your engine is not making the same power it previously made...
If the engine is not putting out the HP it once did... It could be from a lack of fuel flow or weak spark... Check the fuel lines & carb, for the first.
Check the spark Plugs and ignition for the other... :smile:KennyV
I just fixed one of these twins. One of the coils was bad so there was no spark on one cylinder. The intake gasket was also no good so it might have been sucking air. I too thought it was a governor issue at first but you are just running on one cylinder is the problem. Figure out which cylinder it is by pulling both spark plugs and whichever one is wet fouled, that is your dead cylinder, unless you have an intake leak like I did, in which case you'll have to check for spark by holding the wire end next to a screwdriver grounded to the frame while someone cranks the motor.
#9
reddragon
ive seen that too.....the opposed twins are so smooth...that alot of people dont realize when they're running rough..compared to singles
Yeah, the funny thing is that it doesn't even run rough at all, you're just missing half the power and it's difficult to realize it until it's fixed and then you know how powerful the motor should have been in the first place.
I checked spark and have good spark on both cylinders. I also have compression of 110 psi on both cylinders. Fuel flow is also good. There is quite a bit of carbon buildup on the tops of the pistons. I don't have a leakdown tester. Any other tests before I check for internal governor problems?
Yes runs the same with either wire pulled. Still don't know how it could be a grass problem though. If that was the case the governor would kick in but it doesn't. The grass is thicker than the last house I lived in but isn't thick enough that my 16 horse twin cylinder Briggs should bogg down with sharp blades. Plus I am not cutting short or fast. Please don't take this as any disrespect but I have been mowing different grass for years but haven't been messing with small engine work that long. I know it is not a grass problem but it is definitely my mower.
#15
reddragon
governors dont kick in....they maintain speed..............lets be clear.....at full throttle..it never gets to peak rpm?..before blades are engaged......is that what your saying?
I have a Murray with an opposed twin cylinder Briggs. It runs pretty good but when I get in tall grass it does not idle up. I mow at full throttle but it is like the governor never kicks in. I have adjusted the gov but still same result. What could I be looking for?
i've had to deal with opposed engines, and i've found that they have a hard time keeping a steady rpm under sometimes normal work loads. also by the sound of it you may have a internal governor issue. but before taking it in you make want to just play to the motors strengths. opposed engines can produce more horses, but have less torque. so they can pull more, but if it is more than what the motor can handle the opposed will bog down quicker. so if it is just a area of your yard that bogs it down. you might want to try to bum rush it and let the momentum of the blades handle it. if it is a good portion,or most of your yard. try to find a mowing pattern that allows you to cross the tough grass, and then some softer stuff to try to get the blade speed back up, so you can keep moving.:smile:
governors dont kick in....they maintain speed..............lets be clear.....at full throttle..it never gets to peak rpm?..before blades are engaged......is that what your saying?
Yes I understand that governors don't "kick in" but that is just the terminology I use and have always heard. But when an engine starts to lose power under a load you can tell when the governor "kicks in" or "maintains speed" however you want to word it. Just like when you engage the blades and put it under a load. You can hear the governor maintain speed. Mine is not doing that.
#18
reddragon
if its not the grass....and its not grass caked up on the deck....and the blades are sharp...and your mower belt is tight and pulley's clean.......then your engine's lost horsepower......maybe a worn cam....the governor is fine if it holds rpm prior to grass resistance.............also you might have your rpms checked by a tachometer...it may not actually be reaching peak rpm
if its not the grass....and its not grass caked up on the deck....and the blades are sharp...and your mower belt is tight and pulley's clean.......then your engine's lost horsepower......maybe a worn cam....the governor is fine if it holds rpm prior to grass resistance.............also you might have your rpms checked by a tachometer...it may not actually be reaching peak rpm
I thought my belts were still good since I replaced them at the beginning of the year.
Well my primary deck belt broke so I went ahead and replaced both belts. My problem was solved. No more bogging down in thick grass. Now I just have to figure out why my belts wore out that fast.
