While hanging around my old man in the 1950's with his mowers (his trade), I cannot recall any governor springs or "vanes".
Why did B&S introduce the vane/governor adjusted idling ?
It seems this has been a constant problem with the average joe mowing his lawn, bumping into shrubs and tree branches, tinkering with governor springs, etc. Also, it seems that any small bump at the front of a mower could play havoc with the smooth running of the B&S engine.
I recall the old Victas were simply fully manually adjusted by the cable throttle - from stop, through idle to full throttle. No sign of any automatic idling. Once you got used to operating the throttle, you knew where the idling was.
Why was this "manual idling" not continued by B&S ? Was it worth the change ?
Hello SAB Well, Briggs engines in the 1950s were governed, and there would have been an external spring.
There were no vanes because these were internally governed - meaning a crankcase system combined with an external spring.
Later, air vane governing offered a cheaper solution to mechanical governing. These were engines governed by mechanical-pneumatic governing - like Briggs used.
Even later, we see the advent of pneumatic and electronic governing.
I do not feel 'small pumps' should affect governing at all. This must go to engine tuning.
Old Victas were not governed - if you were quick enough, your hand acted as the governor, hitting the throttle in response. This was imperfect.
Mechanical. pneumatic, or electric governors act more quickly than hand throttles. The catch must be the human connection.
SAB, to answer your question, human governing has proven slower than non-human governing used on IC engines.
Great question! -------------------------------- Jack
Same reason manual chokes on cars went out - because the average person does not want to be stuffing around with a lever (granted car wise, the choke was also an emissions issue).
Most mower 'users' (because apparently you don't truely 'own' an 'appliance' - you use it) just slam the lever to the bottom, kick it in the guts and leave it there until they want to stop.
Without a governor, they would open it right up, hit 5000 rpm, and send the con rod out the block and straight through their leg. Add to that the limits on 'blade tip speed' (especially in the US) and you have potential lawsuits on your hands through high revving engines. Besides, they need a governor for some applications like generators, water pumps, and possibly others
Personally, full throttle start, straight back to idle for 1-2 minutes whilst I check everything is off the lawn, etc, then use half throttle - if its thick I bump it up. Just wears it out quicker, uses more petrol and more noise to rev it flat out
Other issues are that slow idle cooks the briggs - I left one idle at approx 1200 rpm for 10-15 minutes once and the petrol in the tank was a solid 'bath water' temperature
Also (this is more tongue in cheek) I couldn't use the words smooth and briggs in the same sentence after using a Honda haha
I guess a similar comparison is with the manual v automatic transmission in cars.
We all can all "feel" when a gear needs to be changed in a "manual" car. Or most of us at least. For the others, then an automatic gearbox does the work.
So, I guess, now all mowers have some form of governing.
Or do they ? Are any mowers still "user" operated ? Can you take the wind vane governing off somehow (easily) ?
The wind vane governor is super easy to remove. Bend a metal tab or two and off it pops.
I took my old ~1959 Pope mower out for its first proper run the other day. No governor at all. Holy hell that was interesting. I wanted to film a "hot lap" with it but one hand was full pushing it and the other was busy trying not to let it run away! A bit of an adrenaline rush, I have no idea when the blades were last changed and them grenading into my legs was always in the front of my mind, hahaha!
I'm going to tweak the cable, but I must say, I do like my governed engines.
Last edited by Mystyler; 26/06/2001:52 AM.
I don't collect mowers. I just require Multiple Mowing Solutions™.
We all can all "feel" when a gear needs to be changed in a "manual" car. Or most of us at least.
I wholeheartedly agree - I have a 4 speed auto and can get it off the mark quieter and quicker than relying on auto. I am in 3rd or even 4th before it would be out of second.
Can't think of any 'non governed' mowers (of course all line trimmers and blowers are user operated (aside from spark over rev shut off). The biggest market (USA) has strict blade speed laws, so the same engine on a 18inch deck might be allowed to go 3200rpm, but a 22 inch only can do 2800 (which really knocks the power out of it)
And we all know how the americans love their 'small' 22 inch decks
No way you can 'guarantee' without a governor of some description it won't go over x rpm. For all the trouble they are, they are reasonably good (although victa were onto something with the G4 - internal governor that doesn't get snagged
SAB, if Briggs were left to the operator to adjust the throttle there would be bits of metal scattered all over the world as they exploded into millions of pieces, they do not like being revved as they are similar to a hand grenade with a loose pin, you never know when the pin might fall out
Hypothetical ..... So what would happen if I took off the plastic vane, disconnected it from the black plastic butterfly clip on the carby and then connected the butterfly clip directly to the throttle control bracket somehow with heavy wire. (Disconnect & save the small idle spring & larger governor spring). No auto governing & direct carby control from the throttle cable.
Then I would have to ask WHY, the vane governors work perfectly. The problem with trying to connect directly to the butterfly is the amount of travel from fully closed to fully open is so small it is very difficult to regulate
I've converted a Briggs to manual throttle before but it was running on LPG , I think I have seen a few manual throttle petrol ones but can't remember how good the throttle control was running unleaded.
There was no need to remove the air vane when I tried the manual throttle.
The governor system is like a cruise control system. It maintains the speed of your lawn mower or outdoor power products. When Briggs & Stratton governors are adjusted properly, they keep your speed steady regardless of engine load - the amount of work the engine must perform.
As has been said above, the governor was put on for a reason. Every engine way back to before the turn of the century has had a form of governing. The early steam engines had a flyweight governor, the early spark ignition engines are governed by lifting the exhaust valve (hit n miss).
Without a governing system the engine will run away, building rpm until it either starts to lean out and slow down because of a lack of fuel/air or it explodes internally.
The early push mowers were built very simply, and as cheaply as possible. They were basically motorcycle engines with a blade. Not to mention being 2 cycle with basically 3 moving parts can achieve higher rpm than a 4 stroke without flying to pieces. Governing came to victa with the G3 carby and they obviously never looked back.
Governing quite simply is a way of maintaining rpm regardless of load. An engine requires more fuel and air the more load you put on it.
Personally I have never seen a briggs engine without a governor. even way back, they were internally mechanically governed. The air vane governor has been around forever and a day, even the internal governor used today is based on the flyweight governor from the days of steam!
The larger problem is the lack of protection from abuse by end users on the linkages and springs, the sprint series in particular, and the end users themselves. If people didn't shove them under trees, branches etc things wouldn't get bent/broken etc. On the flip side of that, without said users mower mechanics wouldn't have a job!
The larger problem is the lack of protection from abuse by end users on the linkages and springs,
Hello Nath and all Govs
I have read that the engine governor was such an important invention, in that it enabled steam and IC engines to operate free of human control. Nath has said that nicely.
It's clear that most engines are governed within limits. If the limits exceed the design then an event will occur.
If the limits are tampered with - by users - then the engine may fail in spectacular circumstances. I've seen examples of that.
Other times, mechanical mechanism age may develop issues ...
Quote
5 August 1976: First and only major breakdown. The air brake speed regulator of the chiming mechanism broke from torsional fatigue after more than 100 years of use, causing the fully wound 4-ton weight to spin the winding drum out of the movement, causing much damage.
Good ol' Big Ben exploded in the 1970s. The governor failed.
Early Victas were designed without governors. A full throttle would not exceed the rpm demands set by throttle valves and porting. The engine wouldn't explode.
I guess Trump supporters would be offended by governors. There's irony in that.
I wish the carby on the Pope was the same. Holy moly.
SAB,
I do wonder how it would fail. I would suggest either the conrod would let go, the bearings may overheat or it would simply melt the piston or rings and seize from overheating (there are limits to air cooling on essentially stationary engines) and possible lack of lubrication due to foaming.
If you're the curious type, I suggest you remove the blades from the carrier before doing anything that might be considered silly...and stand well back.
I don't collect mowers. I just require Multiple Mowing Solutions™.
Hi Jack, A lot of the 2 strokes strength comes from the steel conrod and needle roller bearing big and small end as opposed to the 4 strokes with an alloy conrod running directly on the crank. This design is adequate but not bullet proof
Hi Norm Yeah, I think that's about it. A general rule on 4-strokes is: if the rod breaks at the small end it is due to over-speeding; if the rod breaks at the big end it is due to lack of oil.
