Windy Miller
Semi-Professional Potterer!
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Right! Gotta buy an old mower now and give that a try!
- Thread starter Rob ayre
- Start date
the snooper
getting older by the day
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wouldn't like to guess but before and after doing the valves will give you an idea of how bad the valves were
penfold
Ambassador plenipotentiary
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I use disposable syringes for this; a couple of cc is enough to get even reluctant combustors chuntering away. I'm having to do this to my big chainsaw as the pump valves have gone a bit but I'm too lazy to sort it as it's fine once running.
octo0072000
Member
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big cordless drill on crank pulley get it spinning over
wristpin
Member
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That second lifting of the valve may just be the automatic decompressor doing what it should so don't rush to increase the valve clearance until you are sure . If the ID plate is still on the engine showing a model number such as SRL1017 / 1026 etc , post it and I will give you all the clearances and timing data etc.
On some Mag engines the valve clearances are set by shims in bucket tappets rather than just plain valve stems that can be ground to increase clearances.
Depending on its age it may be pre electronic ignition and have contact breaker points - if there's no spark they will possibly need cleaning.
On some Mag engines the valve clearances are set by shims in bucket tappets rather than just plain valve stems that can be ground to increase clearances.
Depending on its age it may be pre electronic ignition and have contact breaker points - if there's no spark they will possibly need cleaning.
wristpin
Member
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Crystal ball a bit cloudy on that one but from the size of the Hayter 26 !'m guessing either a 1017 or 26 but as they share the same valve settings etc you should be ok with this
https://www.dropbox.com/s/g8y185i6r8xzxzk/MAG 1026 1017 Specs0001.pdf?dl=0
I was wrong in saying shims in tappets - in fact they have graduated tappets (they call them thimbles) and you are supposed to measure the actual gap, compare it with the book gap and order the appropriate sized thimble which "are (maybe were?!) available in 0.05mm increments from 1.9 - 3.00 mm"!
It's now all coming back to me - the last one I did I carefully ground the top of the existing thimble to get the correct clearance - shuussh !
PS. Check the valve clearances with the piston about 1/4" down the bore on the power stroke . That way there is no interference from any cam operated decompression devices.
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octo0072000
Member
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as said big drill/driver on crank pulley get it spinning over and some thin oil down the bore if it's been stood a long time rings might be stuck buy a new plug too
like this
like this
octo0072000
Member
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should be a bolt or nut inside the bit you put the pull rope over might have a cover over it but there will be a bolt or nut in there you may have to pull the cover to see it
those engines need a really good pull to get them going longer the rope better to give a long continues pull
Cobbler
Codger bodger
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Some small engines, can't recall whose, the points cam is on the inside of the flywheel hub. Take off the flywheel & the points close up. Makes it difficult to adjust the points though as you have to do it through a gap in the flywheel.
julianthegypsy
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They need adjusting. No wonder it won't run! Turn the crank until the highest part of the cam is under the points then adjust it to 12 thou for starters, that should get it sparking, and running!
julianthegypsy
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Yup that's it exactly.
