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Stubborn Cylinder head

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Stubborn Cylinder head

Posted by adrian_bates at April 21. 2017

Hi, any tips on getting a 750 cylinder head off ?

All 9 bolts /nuts removed, but it won't shift. Engine is still in the frame.

thanks, Ade

Re: Stubborn Cylinder head

Posted by john_holmes at April 21. 2017

Double check you have all the bolts/nuts out properly, reinstall the spark plugs and then use the kickstarter and the compression should start the head moving.

Re: Stubborn Cylinder head

Posted by robert_tuck at April 21. 2017

I used to slacken the fixings and run the motor till it popped.

Re: Stubborn Cylinder head

Posted by gary_knowles at April 21. 2017

There is 10 studs/bolts.

Re: Stubborn Cylinder head

Posted by christopher_winsby at April 21. 2017

Previously adrian_bates wrote:

Hi, any tips on getting a 750 cylinder head off ?

All 9 bolts /nuts removed, but it won't shift. Engine is still in the frame.

thanks, Ade

As we do not know what you know have a look at the Andover Norton web site at your engine in the expolded diagram. You can see washers that go under the nuts and bolts- have they come off or are they pinched on the studs?

Could be just the head gasket holding it- soak in plus gas.

Try a small amount of Redex or oil down plug hole plugs back n and turn over.

With oil down plug hole leave on compression.

With large lump of hard wood held against fins tap hard wood so force is horizontal and not vertical on fins. This has to be done with care as the fins can be broken.

If this fails nuts and bolts back on but not fully tightened a small amount of fuel plugs in ignition on and kick it over the seal should break as the engine fires.

Big hammers and pry bars are to be advoided as they generally lead to damage.

Re: Stubborn Cylinder head

Posted by robert_tuck at April 21. 2017

Dont hit the fins at all,  if you must a bit of wood under the exhaust port will not hurt.

Re: Stubborn Cylinder head

Posted by ian_cordes at April 21. 2017

the clue here is in 'all 9 bolts/nuts'. As Gary said, there are 10.....

Re: Stubborn Cylinder head

Posted by Andrew Heathwood at April 21. 2017

Adrian

As others have said 10 nuts and bolts - see diagram from workshop manual:

 photo 750-cylinder-head_zpsommclnhi.gif If you haven't best get hold of a workshop manual. Electronic versions are available here: http://www.classicbike.biz/Norton/Repair/NortonRepair.htm and http://www.pdfmotomanual.com/index.php?r=site/page&view=manuales&order=t&key=N&make=1964&lang=ENG

Andy

Re: Stubborn Cylinder head

Posted by David Comeau at April 21. 2017

Andy's pix it the key here. Removeing the head is reverse # sequence.

Bolt #1 is always the last to be removed. If not at tdc, valve spring pressure will always lift the head, unless something is drastically wrong?

On installation #1 is the first to be tightened, and always at TDC with the valve adjusters loosened.

Re: Stubborn Cylinder head

Posted by adrian_bates at April 21. 2017

Thanks all for the quick replies and advice.

Turns out there are 10 nuts/bolts on my head.

Problem solved.

Workshop manual secured, to move to the next stage

Again thanks, have a great weekend.

Ade

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