30D smoking and gov not working

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Valiant Farmer
Posts: 24
Joined: Wed Aug 14, 2019 9:02 am
Location: New Zealand

30D smoking and gov not working

Post by Valiant Farmer » Wed Feb 12, 2020 2:27 am

My 1950 Cropmaster with the 30D motor is causing me some problems...it runs well-ish, but it smokes hot or cold, and if I am running an implement or driving, if I set the throttle at say 1400RPMs, let out the clutch and it will drop to around 800 or so depending. Also on the open road, I can get it up to about 34 KPH. What is the problem? Diaphragm? This is a recently rebuilt motor out of a boat.
Also the decompression lever shaft leaks quite considerably. How do I stop that?
Just did a RPM test, and it idles at 600, and max unladen 2650 RPM.
Many thanks!

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Posts: 2278
Joined: Fri Feb 24, 2012 10:01 pm
Location: Monmouthshire

Re: 30D smoking and gov not working

Post by db2d » Wed Feb 12, 2020 8:29 am

The idle rpm should be no lower than 700 and the maximum should be no higher than 2200.
Check the operation of the rack in the fuel pump and the condition of the diaphragm and the venturi pipe set up.
Has the fuel injection pump been spill timed ? Have the fuel injectors been serviced and the pressures set correctly?
There are ‘ O ‘ rings on each end of the decompression shaft that have to be installed in the correct manner during assembly to avoid shearing damage.

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