STUART

In order to fit a new rotor shaft / sprocket assy the chaincase needs to be split.Those rivets only fix the bearing housings onto the chain casing.It sounds like you may have other “issues” with the gearbox that need attention if its making a grinding noise.

Yes that’s the fella Charlie.Hope he reads this soon.

OK spoke to Jon earlier today and he has nothing but suggested I get in contact with Ian Mackallow ?? as he tells me he is a Tarpen enthusiast.Hopefully he may read this soon.

Thanks Chris.Im sure the engine is not a Villiers one even though it looks very similar but I will give him a call later today.
I do have some thread gauges so I will try to determine what pitch they are (they are a fine thread).

The engine model,type and code numbers should be stamped at the front of the cowl (just above the spark plug).If its had a new cowl fitted in the past then there will be NO numbers stamped on it at all.
The 11hp B&S engine is i think a 25cui (25 cubic inch capacity) engine so your model number stamped on the cowl should start with 25####
The…[Read more]

It will be mid 1980,s.Providing its still the original engine fitted (or cooling cowl fitted) then its easy to date the engine as the reply above.

The second picture is correct.

When the line on the end of the crankshaft is vertical the piston is at TDC.Set the flywheel mark opposite the mark on the alloy back plate (there should be one there somewhere) and then tighten the flywheel making sure the crankshaft does not turn whilst doing so.Ignition timing should then be set.

Make sure any insulating pieces in the contact breaker box are in place as if they are missing the LT current will be grounded (earthed) and no spark will result.Also make sure the magnets on the flywheel are ok.

Put the air filter in a clear plastic bag.Pour a small amount of engine oil in bag.Press and squeeze oil into airfilter then squeeze out any excess whilst still in bag.No oily hands and no mess :):)

Give it plenty of heat and use diesel to lubricate it (WD40 will not work as it simply vapourizes with the heat).Use a good fitting 3 leg puller and it will come of.Sometimes they come of easier when everything is cooled down.

If you are interested i have a few parts for a BJ engine including a very good crankshaft assy, a cylinder head (which still has the copper head gasket in place),oil pump assy plus a few odds and ends.Send me a PM if you wish.

The set of MT lawn aerator tines I used to own had a green and red coloured dot of paint on them from the factory so they are definitely “handed”……if I remember correctly red was the Left side and green was the Right side.Dont know if this will be any help to you or not.

There is a service limit (minimum length) for the plunger but as my B&S manuals are at my workplace I cant look it up for you at this time.The plunger is made from some sort of fibre material and does wear of course.If the points and condenser have not been changed in years then simply fit a new set (unless you have the equipment to check the…[Read more]

Unless that engine has already had a “Magnetron” ignition conversion it will have the contact breakers and condenser located behind the flywheel.B&S part number for a replacement ignition set (points and condenser) is 294628.Set points gap to 020″

If its seized on the big end journal (con-rod / crankshaft) due to low oil quantity and quality then you will need to strip it of course.Personally I would strip it all down anyway so you can inspect and clean every part.

There should be no sideways movement (or VERY little) of the wheels.If you strip it down im sure the wear will be apparent.

No point it getting it tested as they will (or should) only tell you what we have already stated (if it don’t spark with the stop wire removed the coil is dead).

Presuming the engine is equipped with the “Magnetron” ignition coil simply remove the thin,black ignition ground wire (stop wire) from the coil and try again.If it now sparks then you have a safety switch problem.If it still don’t spark then a new coil is required.