Mark
Since I'm stripping the engine, even though the bearings "feel" good I suppose I should change them as a matter of course. How do I get the bearing out of the engine casing for the cam shaft.
And..
The flange of the carby is slightly bent. When I put a straight edge to it there is a gap of about 1mm in the center. I suppose having it machined would be the answer. however I don't have access to such machinery. Should I flat it by hand Can anybody suggest any other way of making the flange surface flat.
Thanks for your help
Cam shaft bearing, carby flange
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Peter Fougere
Re: Cam shaft bearing, carby flange
Ben, A simple fix to this problem is to get hold of a piece of plate glass or mirror, say
between a quarter and half an inch thick,(both these are to all intents and purposes flat),
or even a marble bench top which will be equally flat, then place a sheet of "wet & dry
abrasive paper (oblainable from hardware or paint shops) smooth side down on the flat
surface, then put the carbie flange down on the wet & dry abrasive surface, keep it wet
with water and rub the flange with firm pressure in a figure 8 pattern (which will keep you
from grinding too much from one side). a bow of 1mm will take quite a time to get level,
you could lay the flange on a large flat file to start with and get it nearly flat first. To do
this dont try to hold the file by hand , clamp it in a vice or lay it on your bench and rub the
carbie on it. This method is still used even in professional workshops, and in my youth we
used to do it pretty regularly to Amal carbies which were prone to the problem. Cheers.
between a quarter and half an inch thick,(both these are to all intents and purposes flat),
or even a marble bench top which will be equally flat, then place a sheet of "wet & dry
abrasive paper (oblainable from hardware or paint shops) smooth side down on the flat
surface, then put the carbie flange down on the wet & dry abrasive surface, keep it wet
with water and rub the flange with firm pressure in a figure 8 pattern (which will keep you
from grinding too much from one side). a bow of 1mm will take quite a time to get level,
you could lay the flange on a large flat file to start with and get it nearly flat first. To do
this dont try to hold the file by hand , clamp it in a vice or lay it on your bench and rub the
carbie on it. This method is still used even in professional workshops, and in my youth we
used to do it pretty regularly to Amal carbies which were prone to the problem. Cheers.
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Peter Fougere
Re: Cam shaft bearing, carby flange
Ben, I forgot to say that the grade of wet & dry can be quite coarse, say grit No80, to 120
, finer grades will take too long and the paper gasket will absorb athe roughness left by
the coarser paper. By the way, although I have a well equipped workshop
with milling machine etc, for jobs like this, and for that matter similar things such as reducing
shim thicknesses by a few thou, it is often quicker and just as effective as setting up a mill
or surface grinder. Hand methods are still as valid as ever providing you are not in a
hurry and check the work as you go. With the same piece of glass etc you can check the flatness
of the flange with bearinb blue, Prussian blue oil paint (which is virtually the same thing),
or even a sheet of carbon paper. Good luck, Peter.
, finer grades will take too long and the paper gasket will absorb athe roughness left by
the coarser paper. By the way, although I have a well equipped workshop
with milling machine etc, for jobs like this, and for that matter similar things such as reducing
shim thicknesses by a few thou, it is often quicker and just as effective as setting up a mill
or surface grinder. Hand methods are still as valid as ever providing you are not in a
hurry and check the work as you go. With the same piece of glass etc you can check the flatness
of the flange with bearinb blue, Prussian blue oil paint (which is virtually the same thing),
or even a sheet of carbon paper. Good luck, Peter.
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Mark Huggett
Re: Cam shaft bearing, carby flange
Hi Ben
I see that Peter did an excellent job of describing the carb flange problem.
Re camshaft bearing. The housing should be warmed up to 180°C in order release all shrunk.in bearings without causing any damage. Obvoiusly you had not warmed up the housing sufficiently if the cam shaft was removed and the rear bearing left behind. Best bet is to take an old broken and long screw driver and bend the end to form a 90° right angle. Heat up the housing in your wifes oven (she'll love you for that!) or heat up th outside area of the housing were the bearing is situated with an industrial hot air blower until it is about 180°C. Use the hooked screw driver to fish out the ball bearing while the housing is still hot. Some times a hot housing alone is sufficient, and the bearing falls out by itself.
Good luck!
Regards,
Mark
Mark Huggett GmbH
I see that Peter did an excellent job of describing the carb flange problem.
Re camshaft bearing. The housing should be warmed up to 180°C in order release all shrunk.in bearings without causing any damage. Obvoiusly you had not warmed up the housing sufficiently if the cam shaft was removed and the rear bearing left behind. Best bet is to take an old broken and long screw driver and bend the end to form a 90° right angle. Heat up the housing in your wifes oven (she'll love you for that!) or heat up th outside area of the housing were the bearing is situated with an industrial hot air blower until it is about 180°C. Use the hooked screw driver to fish out the ball bearing while the housing is still hot. Some times a hot housing alone is sufficient, and the bearing falls out by itself.
Good luck!
Regards,
Mark
Mark Huggett GmbH
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Ben Friedl
Re: Cam shaft bearing, carby flange
Thanks Peter and Mark for those very helpfull answers.
Ben
Ben