Thread: Wotcher Guv'nor

the govenor is a magic bit of balancing....

essentially some weights get thrown about with engine speed and some springs try to keep them in check. in a fixed speed engine (like a genset) thats all there is the govenor is set at one speed and will do what it can to make sure that RPM is maintaintained.. Great for gensets bad for cars

so we have what was once known as the variable speed govenor its essentially the same but your throttle pedal links into the balancing act in such a way as to bias the tension on the springs or the weights..

in both cases the springs and weights move the bit of the fuel injection system that controls how much fuel is going into the injectors to feed the engine.

if the weights are winning the tug of war then the engine is going too fast so they will act on the fuel control to reduce engine speed

if the springs are winning then the engine fuel control is acted on to add more fuel as the engine is going too slowly.

think of it this way...

when you stomp on the loud pedal you are not asking the engine to make more power but to make more RPM's

the throttle pedal usually has no direct influence on how much fuel is going into the injectors it acts indirectly by changing the balance point of the springs and the weights.

once you get around all that there are a couple of limits that are imposed on the system by the designers the first is Idle speed, this is the point where the engine idles and the springs counter the weights at the lowest speed the engine is designed to turn at. The other other is the max speed limiter and this is essentially the point where you can no longer influence the springs to overcome the weights which means you cant use the noise pedal to make the engine over rev.

theres lots of ways you can govern a diesel with electronics, air pressure, mechanically (the most common but being replaced by electronic means) hydraulicly or a combination of the above. You can also govern for torque, power or as already covered RPM.

there is also usually a method of causing a shut down, it used to be a case of just winding the springs back till the weights pulled the fuel control all the way off but you can also do that manually as per the old 2.25 diesel and the series, or you can turn the fuel off electrically (like a tdi) turn the injectors off electronically (like a TD5).

thats basically govenors.

Motor revs, spung wieghts do there thang and stop putting fuel in at Xrpm

Easily adjusted via a cap on front of the pump, when you fit the Turbo, you'll have a HEAP more grunt down low, so easier to get the next gear

^^^^I think you've got the long AND the short version of it

Originally Posted by rovercare

^^^^I think you've got the long AND the short version of it

Ta, ta, .

If you want the bloody long version, I have just finished reading a Bosch manual titled "Diesel Engine Management". It was intense. 500 pages. Very good insight if you've got nothing to better to do with the time.


here - http://www.pitstop.net.au/view/produ...ery/plu/15092/
shorter one - http://www.pitstop.net.au/view/produ...uery/plu/8578/

so you got the abridged version then....

Originally Posted by abaddonxi

I've been driving around in the new toy for a few days and I'm noticing there's a governor.

Simon

Check also for restrictions under the pedal as well as the lock bolt under the pedal is adjusted correctly. When I pick up my '88 County four years back it didn't seem to want to rev out as the carpet under the pedal was stopping me getting full travel. That was an easy fix

Ah, swings and roundabouts.

Went out for a long drive the other day and noticed some irritating black smoke.

Drive to the governor, shift up and give it a bit of stick to get it going and instead get the farty noise and puffs of black smoke.

If I did it all with a little less fast pedal everything is fine.

But not quite what I want.

So I'm guessing not enough air, too much fuel, fit a turbo.

More explanations how this works, please.

Simon