Vacume vs. Minimec governers

[SvendH]

Greetings all
Anybody know what is different about them in everyday use,which would the members of the board prefer on their tractor?

[Emiel]

Hi,

IMHO the vacuum seriously adds to the Major experience. The engine charasterics and the sound of the fuel pump clatter etc. A mechanical one is too sophisticated, to modern. The mechanical one might be better if you are working with it.

If you gonna buy one, buy the better tractor, don't worry about which governor is in.

rgds

Emiel

[SvendH]

I agree,vacume is THE governor for a major.could a convert my minimec-super to vacume or would it require an engine-swap?

[SvendH]

Hello,
I am going to start looking for a "donor" for my super`-vacume conversion,and it would therefore be a great help if someone could help me with the serial number of the right pump for it.

[Old Hywel]

I’m puzzled as to why you would want to swap.
Most owners of elderly vehicles consider it desirable to keep their kit to ‘original’ specification, often searching for the correct parts to replace wrong ‘uns. I understand that different injection pumps require their own specific timings, which further complicates matters.
Having run a Super Major for many years, I can guarantee the coupling makes plenty of suitable noise, and has never needed a new diaphragm

[SvendH]

Hywel
I am also interested in keeping her as original as posible but the thing is the engine has been replaced with a new perf.unit which is not so "original" for a 61 super i think.
My plan is to retro-fit her with an early super engine that i have which has a mechanical governer which i am keen on swapping to a vacume unit.What could be more original for a 61 major than a vacume-governed injection pump?
What complicats things more is that I cant tell the difference between lets say a powers and a diesel-majors pumpe which would not i think be compatible with my engine?

[SvendH]

hello!
Well have just recived 1 pc simms vacume type governer and as soon as i have found a couple of other things such as a manifold with a butterfly valve and some control rod links I should be ready to convert "old smoker" to vacume.
As i examined it I looked in vain for a means to ajust maximum revs, is it the big bolt-thing on the nose of the diaphram housing ?
Any ideers gentelmen ?

[henk]

Hywel
What complicats things more is that I cant tell the difference between lets say a powers and a diesel-majors pumpe which would not i think be compatible with my engine?

If the number on the pump cover is SPE 4A 70S ... than it's a New Major.
If the number on the pump cover is SPE 4A 75S ... than it's a Power Major. I'm not sure but I thought that's the same for the Super.

[SvendH]

Henk
Mine is the 75s so it should be compatible with my super.

[SvendH]

hello,
heres an update on governor-swaping,
Now i have the vacume-job built on and fully funktional on one of my 2 supers (the one with loader) ,the other still has its minimec!
I am very pleased with the result,working with the loader at the usual 1100 or so revs the engine aktually feels more grunty and dropping less revs when hard pressed than when it had its minimec.IMO it even looks better than the Mini!
All is not perfeckt though yet,the motor seems to require the cold-start butten even when fairley warm,the same motor with its minimec rarley required this even in coldish weather when the butten has been pressed it fires up impressivley enough.
One more thing,the Minimec governors i have worked with have all had a tendency to hunt quite a lot at about 700 revs which was quite annoying when driving slowly.Especialy with a hot engine….No hunting with vacume
so apart from the startup glitch its win-win !

[henk]

Give a bit throtle when you start.

[SvendH]

Henk
even full throttle and severel seconds winding on the starter dont produce as much as a fart or a wiff of smoke and we are are talking about a motor which is warmed up and was stoppet just half a minuit ago??
the Rack is in the 75% power position,yet it wont react until i push the button and the Rack moves to the 100% stop-then action.
when the engine stops the diaphram-spring automaticaly sets the pump-rack to about 80% power.
moving the throttle leaver only opens the air-intake flap a bit more.
I just think its a bit strange that just 20% or so rack-movement takes you from dead iron to roaring engine.

[oehrick]

You have exactly the same position as I had Svend my de glazing bores and lapping valves in has improved the warm start situation I still need the button for cold starting - pump and injectors were next on the list but the friend of my old mate Terry who used to do a good job at an affordable price has sadly died so need to find another of the old school who doesn't just throw new parts at things. I think the the vacuum governors are better - unless you need close speed control like a generator, they seem to think about a change in load for a moment and then dig into it

[SvendH]

well the main thing is that she otherwise starts and runs fine with the "new" vacume-governor,now where will I find that "old-style" clattering injector-pump clutch for it to complete its rustic image

[oehrick]

Have you got one of the more modern, softer plastic rather than the original rigid Tufnol coupling elements or something different to the Oldham pattern coupling?

Not a difficult thing to make if you really want one and have (or have a mate with) a lathe, the UK brand name for the material is 'Tufnol' and it comes in several varieties named after fish for some reason, the material closest is 'Carp Brand' generically it is a synthetic resin bonded fabric (SRBF), they also do a paper based material but that has a tendency to de-laminate under stress.

At least you are up and running

[SvendH]

its the type with the large black rubber driveblocks,you see on late model supers.

[SvendH]

Did a bit of ground levelling with the vac-major yesterday and now it starts instantly from cold WITHOUT the cold start butten.Perhaps the flunging-spring has come un-stuck ,a happy day it is

[oehrick]

As the youngsters say 'Result!' more likely some running is getting better ring sealing and increased compression

Never underestimate the value of a freely tremulating flunging valve spring