My first Suffolk punch 30, a bit of help!

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Tommyh89
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My first Suffolk punch 30, a bit of help!

Hello all! 
this is my first post, and first cylinder mower. I've always enjoyed a tinker with a project and when this popped up locally as a non runner. I couldn't help myself! I believe I've identified it as a Suffolk punch 30? It's got a good strong spark, and the blades cut paper very nicely. I'd like to get it running! 

now I've always been hands on, and have a understanding of carbs etc. But I'm struggling to get my head around the set up with this carb? Can you help! The speed adjustment on the handlebars appear to be quite stiff, although the cable is free I'm wondering if the mechanism on the carb is needing a good clean, should there be a good range of movement on the speed cable at the carb end?


can anyone advice what this pull lever does? Also the spring on the bottom of the carb bowl should this be tightened or a set depth in? Understand that is to prime the carb? 

this is the bottom of the carb cable, the metal mechanism it is attached to, only seems to have a small amount of movement? 
 

if anyone can give me some guidance this would be much appreciated! Or settings etc I should be looking at? Fresh fuel and an attempt to start will be tomorrow as it's a bit late now! 
 

thank you! And apologies I think the photos have popped out sideways! 

 

 

wristpin
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The handle bar mounted

The handle bar mounted throttle control should be stiff enough to stay where it’s put. Moving the lever to the left should produce a click and a small bit of further movement which is the stop position that cuts off the spark.

It has a governed engine so the throttle cable works in conjunction with an arm connected to the Governor mechanism within the crankcase. The governor tries to shut the throttle but the throttle cable, via a spring, the governor spring, tries to keep it open ; the result being the governed speed.  Once you understand that the linkage starts to make sense.

Tommyh89
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That makes a lot more sense

That makes a lot more sense looking at it! I still suspect the mechanism at the bottom of the speedo cable is stiffer than it should be, requires a massive amount of force to move it anywhere near full speed. 
which doesn't seem correct? 
 

ive seen one or two people change carbs to simple mini Moto/ pit bike set ups? 19mm etc. Is something like this possible with a governed engine? Removing all the crankcase levers etc. 

Geoff Beechey
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No need to change the carby

No need to change the carby they work quite well, work out what is making it stiff to operate, is the cable free to travel in the outer all linkages free and clean. A governed engine will last a lot longer than one relying on the operator to keep the revs at an optimum operating RPM these engines have been running for a long time and many of them without reinvention.

wristpin
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It’s governed for a reason -

It’s governed for a reason - to make it useable !  B******r about with it and you’ll be continually fiddling with the throttle and cursing the day you did it.  Sort the existing set up and you’ll have a useable machine which, presumably, was the original objective. 

 

Tommyh89
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I will have a bit of a mini

I will have a bit of a mini strip down of all the linkages I think! If I can get the hand control to max without feeling like I've popped a muscle in my arm I should be on the right track! 100% would like to keep it all original! 

Tommyh89
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Thanks for all the help! A

Thanks for all the help! A good clean up of the linkages. And about 4000 pulls on the cord and she's up and purring! Tested two hours later, third pull and she's off! The blades are catching slightly so some adjustment there needed. At least she's running nice! 
 

out of interest on the bottom of the carb bowl there is an adjustable spring needle? Should this be set to a certain distance etc? Might sound a daft question, I'm just not familiar with this type of carb
 

Also is there paint available for these? Or similar colours? Not going for concours finish, but easier on the eye finish. Looks a bit sorry for itself at the moment. 

wristpin
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Carb adjustment. Screw it in

Carb adjustment. Screw it in until the engine starts to falter. Then counting the turns unscrew it until the exhaust sounds heavy with just a touch of misfiring. Then screw it back in half the number. From there,  an eight of a turn either way to find the sweet spot.

 

Tommyh89
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That's great, thanks for that

That's great, thanks for that. Can the adjustments be made while it's just been started? Or do the revs need to be up to start making adjustments? 
 

chuffed it's up and running though!

wristpin
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Give it a minute or two to

Give it a minute or two to warm up and settle and then do it at around two thirds throttle.