How can I get a little UMPF to my mower

[SecondMonkey]

Another thing you can do -
B&S lawnmower engines come with an aluminum flywheel, since they use the blade as part of the rotating mass. Often they use the same engines on pressure washers and things, which require a much heavier iron flywheel, but it's the same as the aluminum one. If you swapped the heavier flywheel onto your mower, it would have a little more momentum for thick areas.

This is also another good reason NOT to adjust the governer. The aluminum flywheels are cheaply made and will fly apart with bullet like shrapnel at high speeds. Many go kart racers have found this out the hard way.

 

[IndyIan]

Originally Posted By: SecondMonkey
Originally Posted By: IndyIan
Tweaking the govenor can give you a few more rpms which can help alot in the thick stuff. In fact if you think the mower has gotten weaker over time you should probably check the govenor. If it doesn't react quickly to dropping rpms your mower will bog easily...

I have my lawnboy set up for a bit of "overrev" power, I wouldn't run it overspeed all the time but once it a while its good for the tough stuff.


This is a *REALLY* bad idea on a stock Briggs and Stratton engine. The rod won't take it, and shortly poke it's way through the crankcase. But yes, it would be good to confirm that the governer is operating correctly at the RIGHT speed. If your lawnboy is a 2 cycle then that's a completely different animal...

As for more "power", try synthetic oil, and don't use ethanol mixed gas if you can avoid it.

Mine is an old 2 smoker, they aren't really made for high rpms either but its nearing 30 years old and its getting close to time for a rebuild.

 

[SecondMonkey]

Originally Posted By: IndyIan
Mine is an old 2 smoker, they aren't really made for high rpms either but its nearing 30 years old and its getting close to time for a rebuild.

I don't know much about the lawnboy engines, but most 2 cycle engines have needle bearings and stronger rods. The two things Briggs really skimps on in their mowers. Plus the flywheel coming apart thing is a really important thing to remember specifically with Briggs brand engines.

Now, if you really want to you can get a billet rod and flywheel, open up the exhaust and carb and crank it past 8,000 RPMs.

Your blade might explode though. It's basically just a vertical version of the engine go kart racers use, and they get upwards of 20hp out of them!

 

[tomcat27]

the 6hp doesnt have the cubic inches behind it like the 6.75. My (older, tecumseh) craftsman 6.75 is much larger in displacement than even the 6.5. nothing stops that beast. and it sure is heavy. so, sorry, no magic. that's why alot of engines are now being sold by torque rating or cc's.

 

[yeehaw1960]

Two or more out of five of the Tecumseh 6.75s that come in (on Craftsman's) are DOA. They start pumping oil out of the crankcase vent and refuse to be fixed. The ones that run, run very, very well. It's another motor (also Quantums) I harvest after the decks rust out and the self propel dies (not necessarily in that order).

 

[SecondMonkey]

Right about now is probably the time to start avoiding techumseh motors, I've never really liked them, but now they're basically out of business. Good luck getting parts.

 

[yeehaw1960]

Makes my Summer Ebay sales all the better! People buy the older Tecumseh carbs right up. I can barely keep them on there. That and recoil starters. I have a heaping wheelbarrow full of carbs to rebuild over the Winter. When someone drops off their "worn out" old tecumseh powered mower to me, I grin big because it's like money in the bank! Carb in the wheelbarrow, recoil starter and blade on the shelves, newer wheels on another shelf, and everything else I'm low on at the time.

 

[greenaccord02]

Hey yeehaw, if you have the carb to fit a Tecumseh Eager 1, 3HP Reserve Power engine, maybe we can work something out... Shoot me a PM if that's the case.

 

[lexus114]

Originally Posted By: tpitcher
Sharp blades.

New spark plug.

Premium gas & Seafoam or equivalent.

Clean air filter.




???

 

[kkreit01]

More power=

E3 spark plug
K&N air filter (or any oil gauze equivalent)
93 oct gas with octane booster
(tiny) Tornado in the air intake
add more stickers
remove all shields for weight savings
buy larger wheels
add rear spoiler (a huge one)
remove muffler
smaller/lighter pulley

Seriously, it sounds like you maintain it with "good gas" and "good oil". What about air filter, spark plug, and sharpen blade?

All mowers will bog some when grass is wet and long.

 

[greenaccord02]

I really do like the way my engines run with the E3 plugs. No kidding.

And everybody knows you gain like .5cc for every sticker your mower has.

 

[yeehaw1960]

If it's to replace something you have, send a picture to [email protected] and I'll check to see if I have one. If not, find a pic on the net and send it to me. I don't have a counter full of manuals to figure out what's what unfortunately. But, I do have a boatload of Tecumseh carbs, older and newer.

 

[kkreit01]

Originally Posted By: greenaccord02
I really do like the way my engines run with the E3 plugs. No kidding.

And everybody knows you gain like .5cc for every sticker your mower has.


I actually had good success with E3 in my old B&S also. I have one in my weedwacker as well -- but didn't notice anything special there.

 

[mva]

Contrary to what many people think, high octane gas does nothing to increase Hp or torque for a lawnmower. Plus higher octane gas is less volatile and will make the mower harder to start. High octane burns slower and is needed to avoid detonation in high compression engines.

I can't prove it, but my mower seemed to have a bit more power when I went from dino 30W to Amsoil 0W40. I don't think 5W20 is good advice for a lawnmower.

 

[Hokiefyd]

High octane fuels do not burn slower. All gasoline, regardless of octane, burns at the exact same rate. High octane fuels are less prone to detonation (spark knock), but do not burn slower.

 

[lexus114]

All I know is my small engines start quicker,run better/smoother on the 89 Octane fuel.My CC starts 1/2 a crank in the summer time.

 

[SecondMonkey]

Briggs and Stratton makes the recommendation to use 100 octane LL aviation gas if you're going to be storing your engine for a long time. I'm surprised the EPA lets them get away with that...

 

[mva]

Originally Posted By: Jason Adcock
High octane fuels do not burn slower. All gasoline, regardless of octane, burns at the exact same rate. High octane fuels are less prone to detonation (spark knock), but do not burn slower.


Wrong. Higher octane fuels do burn slower; this is how they reduce detonation. Have a look at the following link:

http://en.wikipedia.org/wiki/Octane_rating

"The octane rating is a measure of the resistance of gasoline and other fuels to detonation (engine knocking) in spark-ignition internal combustion engines. The higher the octane rating, the slower the fuel burns."

Higher octane fuels are harder to ignite and will make your mower harder to start. Also, the only way to get more power from the high octane fuel, on an engine designed to run with regular low octane fuel, is to change the engine design (compression, timing, etc).