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MG MGB Technical - Pro race harmonic balancer

Sized up the balancer to the camshaft before finally fitting it all to check clearances etc. One thing I noticed was that there was a gap. By gap i mean that the cam shaft was short 2.17mm which means that the balancer protudes that amount from the thread/ tip of the cam.

I solved it by finding a good quality washer that is 1mm thick and 2mm larger radius than the balancer and a snug fit to the cam bolt thread size. I centered it to the face of the balancer before then installing the lock tab and cam bolt.

If the pulley was dead flush it wouldnt sit tight, so I figure this is not a big deal... right? Would that 2mm of thread be needed? Should I source a slightly longer cam bolt? Machining the rear flange of the balancer is not something i think sounds like a good idea. I wreckon it should be okay, but what I wreckon might not be worth much! Anyone encountered similar situations with Pro race balancers? How did you solve it?

The cam is a Piper.

JS Ahlund

I tried to edit. The cam bolt will be 3mm less (gap plus washer) once torqued down..
JS Ahlund

Final edit. I obviously meant the CRANKSHAFT bolt. Not the cam shaft. Trouble is having two languages in your head and translating between which gets to be a project in itself. I need breakfast and some tea.

Really appreciate some replies.

Thanks

/Jamie
JS Ahlund

How many threads of the bolt are engaged into the crankshaft?
Art Pearse

Jamie

There should be a gap of around 3mm twixt the end of the crankshaft and the front pulley. Are you talking about a standard pulley or a special one?

Peter
Peter Burgess Tuning

Hi Peter, The pulley is a Prosport for MG. There is a gap of almost 3mm between the end of the crankshaft and the face of the prorace. When I say face i mean the hub face. See attached pic.

When I initially test fitted I figured a washer underneath the lock tab would be better than just the lock tab on its own to apply an even pressure to the pulley to keep it in place. The gap seemed to big for enough pressure to keep the balancer in place without damaging the lock tab which does seem kind of flimsy. Wrong thinking?





JS Ahlund

Art id say almost all of it bar the last 3mm. If I dont include the extra washer under the locktab then just around 2.17mm.
JS Ahlund

Jamie

The standard one is the same it is not a problem. Don't fit a washer/spacer as it is not needed. Does the lock tab fit in the same way as per std item? What was wrong with the old pulley?

Peter
Peter Burgess Tuning

Morning Peter

Okay great. I didnt pay much attention to that part of stripping the engine or perhaps notice how the old pulley sat. Yes lock tab is fine, a good fit its all a good fit. I just figured I should double check instead of make a mistake, like add unescessary "when you think about it" washers. The old pulley was knackered. Rubber was aged and had cracked quiet considerably. I was looking for a serviceable pulley with a better design than the original and came over this one. Nice bit of kit I sourced in Kentucky.
JS Ahlund

This thread was discussed between 19/10/2013 and 22/10/2013

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