Timing side main bearing shim on a MK3

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jimbo

jimbo

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I am rebuilding my MK3 , it was rebuilt several years ago. I found no timing side main bearing shim(#15) as shown in the parts manual. I suppose I could assemble the crank into the cases, and measure the float. I do not remember why I did not install a shim last time, is there sometimes no need for one?
Timing side main bearing shim on a MK3
Timing side main bearing shim on a MK3
 
Item 15 is only 0.003" thickness.
If the main bearings are in the cases checking the float would not be much work but posts over the years have suggested a small correct amount of end float and quite a bit did not make much difference and did no harm to anything.

If you had the bottom end down and had the time and inclinatiion to chase fairy's then why not.
I machined dummy bearings and my own shims to suit (because I could)
It would have to be a large amount of float to be a future problem most likely ?

Could the oil pump drive gear have an effect on things from acceleration to deceleration might even be speculation.
Maybe that is offset by the magnetism of the charging rotor.

Where are the oil pump securing studs. ?

Timing side main bearing shim on a MK3
 
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I will sell my precision mounting bracket (bent from authentic metal) and dial indicator for a price substantially less than $700.... what, no takers?
I didn't find any shims and when I checked the reassembly end float on the '72 it was .018" as I recall. It seems my crank was inadvertently built within specifications.
 

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Atlas Commando said:
I will sell my precision mounting bracket (bent from authentic metal) and dial indicator for a price substantially less than $700.... what, no takers?
I didn't find any shims and when I checked the reassembly end float on the '72 it was .018" as I recall. It seems my crank was inadvertently built within specifications.
Click to expand...
.020" float found with new bearings( superblends both ends) gonna leave it alone. quote Jim Comstock in another thread ;


None of them were shimmed from the factory.

You can shim it if you would like but for normal use it isn't needed unless the end play get's over about .030. Jim



Timing side main bearing shim on a MK3
 
My opinion is most over react to end float and these engines seem to like a bit of end float and after everything is bolted up and together the end float seems to be less, after 43 years my bottom end has been apart 3 times 2 times for complete rebuild and the third time to replace crank cases, I never worried about the end float and just put it back together, my motor has done a lot of hard miles from my youth of flogging it to high speed cruising to now still ride and push it hard even at 60 years of my age and for most of its life it was a everyday ride, my motor is not stock and has a few good things done to it and the only thing over size is the bore.

Ashley
 
I consider it therapy:cool:, also I do an inspection while scrubbing.
 
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