B&S classic 35

[openspaceman]

I've just been given a little used sovereign push along mower with this engine as a project, it hadn't been used for several years and was said to be a non runner. It had no oil in the sump and seemed a little stiff to turn over until I realised the dead man's handle has some sort of brake on the engine, anyone know what it acts on?

 

Anyway with fully synthetic 5W engine oil and aspen 2t (that's the only engine oil and fuel I had) it started on the second pull.

[mikerecike]

It's a little brake shoe that spring engages / disengages with the edge of the flywheel - The mechanism includes the kill wire / switch too (from memory).

[chuck norris]

It connects a small break pad, that stops the flywheel from turning.

 

mikerecike I don't think the b&s classic has, an electrical kill switch

[openspaceman]

It's a little brake shoe that spring engages / disengages with the edge of the flywheel - The mechanism includes the kill wire / switch too (from memory).

 

Okay that makes sense and looks right. I have no use for a mower so can this engine take any axial (side) loading from a belt and pulley?

[openspaceman]

Okay that makes sense and looks right. I have no use for a mower so can this engine take any axial (side) loading from a belt and pulley?

 

I meant radial load

[mikerecike]

I don't know - it's how sit on mowers work and self propelled mowers drive via geared pulleys - not sure how much side loading is involved? One thing - the engine is designed to be used with crankshaft vertical. Question - is there enough mass in that small engine flywheel - not sure if the weight of the blade is factored into the design???

I guess the tension on the belt is the critical factor.

[slim reaper]

 

mikerecike I don't think the b&s classic has, an electrical kill switch

Not even operated by the throttle cable???

[chuck norris]

Not even operated by the throttle cable???

 

From what I know, the classic has no electric kill switch (coil and spark plug are directly connected). But instead It relies on a mechanical system.

[chuck norris]

Okay that makes sense and looks right. I have no use for a mower so can this engine take any axial (side) loading from a belt and pulley?

 

If you are planning on mounting it vertically it will seize very quickly, as the Oil dispersal thing only works horizontally, meaning it would be equivalent to running the engine without oil.

[GardenKit]

All Briggs engines, including the Classic, have an ignition kill switch which works by grounding the coil. In the case of an OPC (engine brake) model such as this, the switch is a contact on the brake plate at the rear of the engine and is operated by the OPC bail bar at the same time the brake is applied.

If it was not there the engine would not stop quickly as the brake pad is very small.

 

The vertical shaft engine can only be mounted in the vertical position, you could use it to drive a pulley or sprocket, but most drives of this type would be taken from a horizontal shaft.

 

The bottom crank bearing is just a plain bore in the sump, but it is lubed and will take a radial load OK, it would not take a high load, but 3.5hp is not going to power a high load anyway.

 

The engine will be fitted with a light flywheel, so will not start properly without a blade fitted. (OK, someone will argue that it will start, which it may. But not without 'kicking back' and whipping the pull handle through your fingers)

 

The hayterette is particularly easy to start because of the heavy blade carrier disc, which gives a good flywheel effect.

 

If the engine is used to power a drive, then it should be via some form of clutch, so the load will not serve as a flywheel.

 

All in all, I would say leave it alone and use it, or sell it, as a mower.