Author Topic: JP3 overload cam  (Read 292 times)


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JP3 overload cam
« on: May 31, 2020, 08:08:18 PM »
I have taken on a JP3 in a narrow boat and as itís a new engine 5o me I thought I would read the manual regarding starting the engine. This states that the overload cam should be rotated up and that it will release back once the engine has started  I located the cam but it doesnít seem to do anything and if rotated just falls back to its original relaxed position. The engines starts well if itís not in tickover or idle on the speed wheel. If itís left at idle it does not start suggesting little or no fuel is getting through.


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Re: JP3 overload cam
« Reply #1 on: June 01, 2020, 07:55:18 PM »
Ahhhhh the venerable Lister JP, a subject which I am familiar with.

You refer to the overload (excess fueling) protection device on the end of the fuel pump rack, to start the engine you lift the overload stop and move the fuel pump rack as far as it will go in the maximum fueling direction.

When the engine starts, the governor quickly moves the rack, and the excess fueling device reverts back to its normal overload protection position.