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Dominator 99 cylinder head tightening

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My recently acquired 1956 Dominator 99 is leaking oil from between the cylinder head and the barrel and soon I will have to remove the aluminium head and replace the gasket.

In the meantime I have checked the tightness of the nuts ( cold ) as per the recommended sequence and for the front and centre nuts which are in a deep recess I purchased a long box spanner from  RGM which unfortunately is a poor fit and too soft and is of no use. Although I have a comprehensive socket set none of which are slim enough and so far I cannot find on the internet a suitable long slim imperial socket . Can anybody recommend from where I can purchase a good quality imperial long slim o/d  socket that will get down into the recesses so that I can confidently torque up the head.

Any advice re., gaskets would also be welcome.

George

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When torquing down my cylinder head, I found 1/2" drive sockets too bulky, so I started grinding them down on the outside.  Then I had the idea of using 3/8" drive sockets.  They are more compact, and fit into a heavyweight Norton twin head.  They have ample torque capacity.  Problem solved.

In the '80s when I bought the 3/8" drive sockets, lots of people in my classic bike club thought it was a silly idea.  A couple of years later, most of them had a 3/8" drive set.....

Paul

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3/8" drive are much more useful for jobs like this. I don't have a full set of Whit sizes - just the more useful smaller  ones. The trusty Snap-on 1/2" ratchet still comes in useful for wheel nuts, gearbox bolts etc.

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3/8" drive is the way to go. Including an adapter so you can use 1/2" sockets.

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My 3/8" drive torque wrench only goes to 40 lb/ft, so I got a 1/2" to 3/8" adaptor so I can use my 1/2" drive torque wrench for higher torque items like engine sprocket nuts.  I do wish I had a means of torquing gearbox sprocket nuts to accurate figures

For the three nuts on a heavy twin head (below the exhaust ports, and between the cylinders at the rear), I use a spanner and spring balance

Paul

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hello  you start in the middle with number 1 head nut 5/16 then 2 to 4 3/8ths on both sides of the head 5 to 7 two under the front fins and one at the back under rear fins  last two 8/9 are 5/16  at the front of the head  now all 5/16 nuts are 20lb  and 3/8 bolts are 30lb  box spanners are best for the head nut at the front  fit a socket on top to use the torques rench  and get you set of crow foot socket  in imperial whitworth  happy spannerig yours anna j

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I'm rebuilding the bottom end of my 99 engine but have hit a snag with regard removal of the inner roller race from the drive side of the crank. I'm using tyre levers but with no success even after heating the race with a hot air gun. Ideas welcome.

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I would grind a slot in the bearing using a Dremel or similar and split the race with a chisel. The bearing should be a light drive fit and if necessary I would ease the shaft down for the new bearing.

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A fellow club member heard of my plight and told me he had the appropriate tool. This comprised of two half moon shaped pieces which bolted together to form a wedge behind the inner race. The two halves were pulled tgether by bolts. Once gripped thus, the second bit of the tool screwed into the two halves, over the end of the crank with a bolt in the centre that could be tightened to draw the whole device off complete with  bearing. Brilliant!! Job done!

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Go to the screwfix website and search for 

"Bearing  separator and puller ".

For £20 it seems good value to me - at that price it isn't worth trying to make one.

George.

 


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