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Odyssey
08-20-2007, 09:51 PM
I have a mature MW Powrkraft 18/42 mower with hydrostatic transmission for which I have zero documentation. The engine is a Briggs Stratton V-2 flathead which doesn't seem to want to run properly any more. It is very sensitive to 'aged' gasoline (more than a couple of weeks old). It starts fairly easily when choked, but is very tempramental from then on. It runs pretty well under load (blades engaged) but will not idle if not under load. Lopes like an antelope at more speed and dies at idle speed!

Two questions. Any suggestions about why it has become so delicate?

Also I cannot find any information about the engine on the mower. No numbers anywhere that I can see. Any guidance as to how to determine exactly what it is so that I can buy a service manual?

Many thanks.

Restrorob
08-20-2007, 10:09 PM
Service Manual part# 271172-4/99 will cover this engine.

You may want to start with the fuel system, Remove the carb and clean/install a rebuild kit. The fuel pump diaphragm is most likely hard also. Then check/clean the fuel tank, Flush the fuel lines and replace the fuel filter and spark plugs.

Look on the front cylinder covers just below the spark plugs for the model/type and code number stamping.

Odyssey
08-20-2007, 10:27 PM
Restrorob,

Great stuff! Will get onto it soonest.

("soonest" in my circumstances means dependent on air temperature [I live in Texas], age constraints (good start into the second half of my life [60-120]), and mechanical inaptitude.)

Please expect me back in a few days with more questions.

Many thanks.

Bill Kapaun
08-21-2007, 03:16 PM
Is it a V-2 or opposed twin? Vertical or horizontal shaft?
http://www.outdoordistributors.com/Briggs_And_Stratton/briggsmodelid.html

Besides the engine model & type#'s telling us which engine you have, the code# tells when it was built. This can often be useful for determining the age of the tractor, which then can be useful for finding a manual for it.
Also, look on the tractor for a serial# that starts something like GIL or TMO. "Sometimes" these can be crossed to another tractor.
Rob gives excellent advice, but first I'd look for major vacuum leaks, like the carb mounting bolts being loose etc. Spray something like WD-40 around any intake"joints" with the engine running and note if the engine speed/sound changes.
BTW, have you changed spark plugs? If you haven't that can sometimes "cure" a lot of ills.
How is it with the air cleaner off?
Let us know what you have done to it to eliminate that from our suggestions.