STUART

I know the engine is the excellent Italian made Aspera 4 stroke.Im sure they had a cast iron / sleeved cylinder bore and proper valve guides fitted.

Have just renewed mine Charlie.

BSA 320 engine ???.I would think SAE30 oil should be fine.

It may be that the filler plug is also used as a drain plug (which would mean removing the tiller assy and turning it upside down for the oil to drain).The correct amount and specification of oil to replenish it would be given in the machines owners manual.

The Villiers “Lightweight” carburettor needle in the middle of the slide is adjustable by the small brass screw on top of the slide.Screwing it in weakens the mixture and screwing it out richens the mixture.Adjust the needle so that the length exposed at the bottom of the slide is 2 3/8″ (two and three eighths of an inch).This is the standard…[Read more]

Remove the crankcase drain screw (there are actually 2 of them but you only need remove one) to drain the excess fuel mixture in the crankcase.I remove the screw on the magneto side crankcase half and then tip the machine forwards.You may find it a bit fiddly to remove and refit these drain screws but it has to be done as the engine will never…[Read more]

Has the bronze worm wheel stripped its teeth ???.If its been abused / poorly maintained then you may have to get inside the drive train to see whats going on.

Howards are one of my favourite machines.I have a Howard 400 rotavator and also an old Gem.My father still has the Howard 350 rotavator which he bought brand new in 1967.They don’t make em’ like they used too !!

The company was founded by an Australian guy called Arthur Clifford Howard and was called “Rotary Hoes Ltd”.The company was then brought out many years later in approx 1985 by Dowdeswell Engineering of Warwickshire (Roger Dowdeswell designed and made ploughs and other farm implements).They are no longer in business.We used to buy Howard spare…[Read more]

The chaincase and handles are Westwood as Wristpin has already said.The engine is a Briggs and Stratton.

The bolts / threads will be UNC

I agree with wristpin.The B and S valve spring compressor is an excellent and easy tool to use but I have done many hundreds of valves over the years using said tool.I have also used it on other manufacturers valves springs that it was never designed to compress !
Most times there is no need to use the tool when removing the key hole retainers as…[Read more]

First set the points gap to 012″-015″.Then loosen the flywheel on the crankshaft.Position the piston at TDC (the mark on the very end of the crankshaft will be at 12 o clock when piston is at TDC).Turn the flywheel so that its mark / arrow is opposite the mark on the alloy backplate.When turning the flywheel and also when retightening it the…[Read more]

The “correct” JAP engine for a Howard Gem should be a dry sump type engine (the fuel tank has two compartments…..one for petrol and one for lubricating oil).I have a Gem too but I cant remember what model the engine is called.It appears yours has had a conversion to a different engine.As you say its either a model 5 or 6.The magneto you require…[Read more]

The mark (line) on the end of the crankshaft on the above photo tells you when the engine is at TDC (Top Dead Centre).If you turn the crank so that the mark is at the 12 o clock position the engine will be at TDC.
Set the points to open at 5/32″ BTDC.Hope this helps.

I do like that :):).Be a shame to use it.

The carburettor used on this engine spec was the Villiers “Lightweight” and used a round “oil bath” type air cleaner.I have a complete Clifford MK1 rotavator with a seized engine which I have kept for spares for my other example.I would be happy to sell it though if you are interested ??.BTW the tyres are no good.

It looks like the actual rotavator is a Cliffold MK1 from the 1950,s in which case the engine is a 147cc Villiers MK25C 2-stroke.

Its diesel powered whatever it is.

Auctions are your best bet.