When the machine shop balanced my engine, if I remember correctly they balanced
the crank and flywheel separately. Then they where put together, including the
pressure plate and crank pulley, and the whole assembly was balanced, . The
machinist put marks on everything so it all could be put back together exactly
as it it was balanced. This engine will freely rev to 7000 rpm!!
Dereck C wrote:
> Ok, I reread the your message (Lawrie) and I think I got the whole deal.
> 1/4 is there for timing the block to TDC if do this by utilizing a hole in
> the bellhousing (which I believe a B doesn't). If you don't use the mark,
> it doesn't matter which side is up or down. I think I was trying to
> overanalyze the whole situation. I was wondering how a machine shop would
> balance a fly wheel (separately) to account for the difference in the weight
> of the crank. When in fact it is independent of the crank and the mark is
> there for convience of bringing an engine to TDC. Just like me to over
> complicate things.
>
> Dereck
>
> 1970 MGB
>
> ----Original Message Follows----
> From: "Lawrie Alexander" <Lawrie@britcars.com>
> To: "Dereck C" <derex39@hotmail.com>
> CC: <mgs@autox.team.net>
> Subject: Re: Flywheel
> Date: Thu, 27 Jul 2000 07:38:56 -0700
>
> When you realize that the 1/4 mark represents "one slash four", not "one
> quarter", that should answer your question, Derek. If number one piston is
> at TDC, number four must be also. If the 1/4 mark is at the top at the same
> time as the numbers one and four pistons, then that marks presence at the
> top of the flywheel indicates that numbers one and four pistons are at TDC.
>
> If you put the flywheel on 180 degrees from that position, then the mark
> will not be telling the truth. It will say that one and four are at TDC
> when, in fact, two and three are.
>
> This all dates back to the days when some engines had an inspection hole on
> the top of the bellhousing, through which the 1/4 mark could be seen when
> you were trying to set the engine at TDC. Since the MG bellhousing does not
> have such a hole, the 1/4 mark no longer serves any real purpose.
>
> Lawrie
> British Sportscar Center
>
> -----Original Message-----
> From: Dereck C <derex39@hotmail.com>
> To: mgs@autox.team.net <mgs@autox.team.net>
> Date: Thursday, July 27, 2000 6:01 AM
> Subject: Flywheel
>
> >It is proceeding at a snails pace but I am progressing. Yesterday I
> >performed step #2,534b the installation of the flywheel (on a complete
> >engine rebuild). Checking my many manuals (Haynes, Complete Guide...,
> >Twist's rebuild) they all point out how to align the flywheel to the crank
> >flange. Align the 1/4 mark on the flywheel with the corresponding mark on
> >the flywheel flange. I see the 1/4 mark on the flywheel but not on the
> >crank. In the Haynes manual there is a mention of the mark being up when
> #1
> >is TDC (the picture shows the engine upside down, so what is up?).
> >
> >I have my engine with #1 at TDC and I installed the flywheel with 1/4 mark
> >at 12 o'clock (engine standing up right). Is this correct? What happens
> if
> >you get it 180 degrees out of alignment (the only other option)?
> >
> >Thanks
> >
> >Dereck
> >1970 MGB
> >________________________________________________________________________
> >
>
> ________________________________________________________________________
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