ATCO Groundsman 28 inch mower.

[vhgmcbuddy]

Good news on the carb. It has been identified as a s 19 villiers and have now also ordered a repair kit .

[vhgmcbuddy]

Have recently mentioned,and it shows in the video that the engine seems to run fast even when the throttle cable is slightly open. I thought that maybe the goveners may be not set up correctly. When I look inside the inlet manifold the flap is fully open when engine switched off,also when you try to lift the connecting rod which has a spring on it there appears to be quite a lot of effort needed to alter the flap inside the manifold. can anyone explain how to set up assuming whatever is inside the engine is correct.

[wristpin]

With the engine running the internal centrifugal fly weights will try to close the throttle plate. This closing force is opposed by the tension of the throttle cable acting through the governor spring. When the two forces are in equilibrium you have the governed speed.
So with slack in the cable the throttle plate should be closed,held slightly open by the idle stop screw. If the throttle plate is fully open with the engine running It is possible that the governor arm is incorrectly positioned in relation to the shaft connected to the internal mechanism. The throttle plate being open when the engine is not running does not necessarily denote a problem.
The inability to achieve acceptable idle rpm in an oldish engine is often down to throttle spindle wear etc rather than a governor problem.

[vhgmcbuddy]

Thanks Angus ,so really I need to start it and see if the weights system in the engine is making any difference to the linkage connected to the manifold butterfly . if NOT then maybe the spring is to strong and not letting any slack develop during varied engine speed if its possible.

[wristpin]

A rough test is, with the engine running, to try and move the governor arm in the direction that will open the throttle plate (butterfly) and as the engine speeds up you should feel the governor trying to oppose you. Amongst others Both Villiers and JAP achieved governor control use using “ungoverned” carburettors by inserting a throttle butterfly into the inlet manifold -I guess that this is what you have.

[vhgmcbuddy]

Yes ithink it is i will try this after repairing carb. thanks

[vhgmcbuddy]

ARGH ! Forgot to mention to those who are helping me with the governor set up,there is no throttle cable connected to governor linkage and does not look as if there has ever been one. Maybe the carb has been changed and the governor is set on max rpm so the carb is working the engine on its own merits.open to all to reply.

[andyfrost]

John , it’s a slide type carb , and would certainly have had a throttle cable.

Andy.

[vhgmcbuddy]

andy its a slide carb and it has its own cable,but there is no sight of a cable between that and governor linkage.will go and take a photo of whats there for you.

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[andyfrost]

Then all seems in order John , the cable merely operates on the carb slide , there is no cable for the govenor linkage. The MK15 engine on the Howard Bantams works on exactly the same principle , amongst a few others.

Andy.

[wristpin]

An image would help but as Andy says the throttle cable will operate the carb slide. As I said in my earlier post the governor arm may well just operate an auxiliary throttle butterfly in the inlet manifold. I that case it won’t have another cable and the sping connected to the governor arm will probably be anchored to a bracket – maybe via a threaded rod and lock nut to allow for adjustment of the top no load rpm.
An image of the governor arm etc will help.
Angus

[vhgmcbuddy]

angus, photos uploaded a little up the thread

[andyfrost]

John , externally it looks as it should , when not running the butterfly should be in the wide open position , when engine starts , it should then govern down. When you have it running , can you feel any manual resistance on the govenor rod , in other words feel it trying to shut down , if you can’t , it could be an internal problem with the govenor weights.
One other point , have you removed the linkage from the govenor shaft , and not refitted in the same position.

Andy.

[vhgmcbuddy]

Andy. Have not moved rod but maybe the owners befre could have set it up wrongly. When i get fuel needle and seat will try what you have suggested.

[darmic1]

My Mk15 on the Bantam has the same Governor set up…… no linkage from the actual carb. The Governor butterfly is fitted in the inlet and is operated by the ‘draw’ of the piston on the downward strokes. Ive got a photo, just need to find it……

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