On 26/10/2012 17:45, Baz wrote:
Rod wrote in
:

On Wednesday, 24 October 2012 18:24:54 UTC+1, Baz wrote:
David Hill wrote in

:





I'm a bit confused about the engine on this one. You say it's a
Hatz

diesel, then you say it has a Kohler engine.



He said a Hatz mower. Baz is right see, except it is a petrol
engine.

http://www.rescuingthepast.co.uk/Howard_Gem.html



I only know of Kohlers as petrol engines. The Hatz diesel was a 2

stroke diesel engine, and a good one. So I wonder if it's had an

engine transplant at some point, it's often the case with old
Gems.


I can tell you a certain amount at least about operation of the
Hatz

diesel if in fact that's what it is. The Kohler petrol engines as

fitted to the Gem were pretty much standard industrial engines
that

should be self explanatory to anyone experienced with larger
petrol

driven garden machines. Try online for facsimile manuals, parts
etc.

There used to be a rump of Dowdswell - the company that took over

the brand after Howard went bust and you could get some spares
from

them but I don't know if they're still going. A local firm that

serviced our old Gem always seemed to be able to get bits and
Gems

are still being used by many landscape firms so you should be OK.



Rod





I don't know if I am missing posts but Baz said it has a Kohler
K301T


engine.

No mention of Hatz engine, He also said he has had it running.

I am sure that he can tell the difference between petrol and
diesel,

and can tell if the engine has a spark plug or not.



Confusion over I think.

It was bought new with a Kohler petrol engine, as it says on the
paperwor
k,

and was later fitted with the Hatz diesel in the 70's so it could use

cheaper red diesel. I have never heard of any of the two engine

manufacturers before so it's very exciting really. The guy still has
the


Kohler engine according to his son and that is mine too, just have to
fin
d

it and cart it home. What do you do with this?

I am tempted to restore this beautiful machine, but for now it is a
tool


and it runs nicely, a bit rattly.



Baz

No problem, they're both good engines. Go get the Kohler engine, it's
well worth keeping and Kohler is still going so spares should be OK.
Am I to take it that you've had the Hatz diesel going? If so you
obviously know the procedure for starting etc. For others who may be
interested. The Hatz is a 2 stroke single cylinder air cooled diesel.
Starting is slightly different from other more common small diesels in
which a decompression lever is flicked over at a strategic point when
you are swinging on the handle (you need 3 hands for this) On the Hatz
there is an indexing knob on the side of the engine - fully turned is
full decompression and as you swing the engine over the decompression
clicks off a click at a time - as small diesels go it's a dream to
start. For cold weather starting there is an L shaped lever in the
cylinder head and this can be removed to insert a kind of fibrous
'match' red at the end like an old fashioned match into the end of the
plug. This ignites on compression and acts like the 'glow plug' in
other engines. One little quirk which may be disturbing the first
time it happens is; if you stall it on a housebrick or such, when you
restart it after dislodging the obstruction it may (being a 2 stroke)
start backwards and blow the oil out of the oil-bath air cleaner -
never mind no harm done, refill the air cleaner and start again, this
time all will be normal. Oh and it runs forever on a tank of red
diesel. The Kohler in the housebrick situation may kick it out and
inflict serious pain on your shins - a mate of mine used to wear
cricket pads on newbuild sites)

Rod


Thanks for the info.
When I was passing this over the allotment today, and was splattered with
drops of mud I was thinking what would happen if it stalled and stroked
backwards. I think I have some cricket gear somewhere.......

Baz

This is the sort of thing that needs pruning.