[vhgmcbuddy]

After lots of adjusting and modifications we’re finally there apart from reducing idle speed.

[vhgmcbuddy]

What is the best thing to do about the spring loaded felt pad, which I suppose is designed to lubricate the contact breaker cam? Can I restore the old one in some way (soak it in petrol, or wash it?)? Or do I need to buy a new one (Villiersparts have them)? Presumably it needs to be soaked in oil? What sort of oil?

Thank you – Rowan

[vhgmcbuddy]

I know this is a very old post and is probably of no interest to anyone, and I know the recommendations to get a proper magneto test done, but for interest, these resistance readings are very similar to the ones I got today from my coil (from an Allen scythe with Villers 25c engine): 0.5 ohms for the primary, and 2.72K for the secondary.

Rowan

[vhgmcbuddy]

One more question:

7. My magneto has no cover over the round compartment containing the contact breaker. I don’t know whether it never had one, or whether a previous owner lost it. The spring clip that is designed to retain the cover in place is there. Do I need to find one or make one? Does any one sell these?

Thank you – Rowan

[vhgmcbuddy]

Thanks Angus
But it’s not hunting, has a smooth tick over to my ears. The issue is inability to increase revs by use of the throttle.

[vhgmcbuddy]

Just a thought.
Hunting may be caused by wear / maladjustment of the governor or it may be the governor reacting to another cause such as a restricted maladjusted fuel supply. The simplest test for that is to partially close the choke. If it smooths out the hunting it points to wards a carburettor issue rather than a governor one.

[vhgmcbuddy]

Could be Andy but I’ve tried increasing the governor spring tension (you can change the position it’s secured to the air cleaner housing) but then can’t get enough push from the cable. I figure if the spring pushing on the end of cable were stronger it would then be possible to adjust the governor spring to suit. I’m guessing with the too weak cable spring friction is coming into play.

[vhgmcbuddy]

Finally here’s the view ins the barrel, the end of the throttle cable is visible. Behind the circular washer is a second spring. I reckon it’s this spring which provides the thrust on to the rod and this has weakened so there’s insufficient force to move the governor lever.

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[vhgmcbuddy]

And here’s the barrel with the rod poking out with the big spring behind

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[vhgmcbuddy]

This may explain better. Here I’ve removed the barrel which screws into the green collar I’ve indicated. At the other end of the collar you can see the end of the governor lever the rod acts on.

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[vhgmcbuddy]

Oh yes Andy. It revs fine if you move the governor lever. It’s just that the thrust from the rod onto the governor lever is insufficient.

[vhgmcbuddy]

So here’s the set-up. The first photo shows the cable entering the barrel. The second photo shows where the barrel is in relation to the governor.
On reflection I think that the thrust on the rod at the other end of the barrel is provided not so much by thrust from the cable, but by the spring located between the cable end of the barrel and the plate in contact with the rod. If that’s the case it would imply that the problem is basically that the spring has weakened. Does this sound reasonable?

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[vhgmcbuddy]

Yes Geoff. I’ve been fiddling with it today and come to the same conclusion. Effectively the throttle cable has to push against the governor lever to achieve running speed, when you close the throttle for idle the spring on the governor closes the butterfly.
The throttle cable enters one end of a barrel which is secured to the machine. Inside the barrel is a spring pushing on a small cylindrical plate, the plate pushes on another spring which acts on a rod in contact with the governor lever. It’s clear someone has had a fiddle with it in the past. I’ve managed to get the bits inside the barrel to move freely but I can’t even with many adjustments of the spring tensions get enough thrust on the rod to open the butterfly. Or at least I can but then there’s insufficient tension in the governor spring to return the butterfly to idle when you close the throttle. I’m getting a bit stumped. I’ll try and post some photos once I’ve reduced them.

[vhgmcbuddy]

Yes Andy, much quieter. But at least I can run it up whenever I like without feeling guilty about the neighbours.
However I still have a SIMAR to keep them amused!
Next plan is a winch for the truck; I’ve chickened out of driving it up!
I’ve got to sort out the throttle which doesn’t work at the moment. Cable goes into a barrel mechanism the other end of which is in contact with the governor. I’m confused as to open the throttle causes the cable to pull at the point it enters the barrel but to increase revs it needs to push on the governor at the other end. I’m thinking I’ll have to have it apart as no adjustments work.

[vhgmcbuddy]

By the way, what should the torque figures be for the cyl head bolts ? My B&S repair book states 140lb/in. So I am guessing it should be the same for a Tecumseh.

The Tecumseh book says 12-16 ftlbs so with unlubricated threads you can afford to increase a bit from your BS setting.
Valve clearances. My Tec book says 6 thou inlet and 8 for the exhaust on the older engines. Small side valve Tecumseh have always been sensitive to the exhaust clearance . Set it on the wrong place on the cam and you will end up with a huge gap and wrist spraining kick back .
BS small side valves have always been 5-7 inlet and 7-11 exhaust for early ones and 7-9for later ones.

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