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Dommi 99 Cylinder Head Removal

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Dommi 99 Cylinder Head Removal

Posted by Bob Matthews at February 11. 2017

I would like to remove the cylinder head without removing the engine and gearbox from the frame.  Is this possible as I can't seem to find any specific info on it, or am I wasting my time and need to remove the engine first?

Any info would be gratefully appreciated.


Dommi photo Dom.png

Re: Dommi 99 Cylinder Head Removal

Posted by David Cooper at February 11. 2017

The short answer is: yes.

Do you have a manual?  Both Haynes and Neill describe it and Haynes includes it in a list of things that can be done without removing the engine.

It is a bit of a Chinese Puzzle to extract it from the gap between the barrels and the frame - partly because the pushrods have to be held up all the time.  There's discussion elsewhere on this site about holding them in place (rubber bands, pet octopus, etc) and relocating them afterwards.  And don't forget there are no less than ten fixings (including the one underneath at the back).

Have fun!



Re: Dommi 99 Cylinder Head Removal

Posted by John Shorter at February 11. 2017

First, get an owner's manual!  Then check you have the correct spanners.

Re: Dommi 99 Cylinder Head Removal

Posted by Bob Matthews at February 11. 2017

All is good, thanks guys.

Once I realised that by using some packers underneath the head to hold it up fairly close to the frame top rails, the pushrods could be lifted high into the head to clear the barrels and the pushrods wiggled out.  Very simple and easy in-fact once you know how.

So the next job is to re-fix the broken top fin on the right hand barrel.  It had been badly welded at some time in the past and I presume it will be better to braze it back together rather than weld - as welding is notoriously difficult in cast iron?

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Re: Dommi 99 Cylinder Head Removal

Posted by terence_rafter at February 11. 2017

I've found silver solder best.

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