[Healeys] A bit of tuning advice - update

[Bob Spidell]

  re: "One piece of advice was to retard the ignition and see what happens. I did this ... and it has fixed it! But now 
the timing mark on the flywheel is about half an inch out, but it runs normally. I assume this doesn't matter?"


The (sole) timing mark on the crank balancer outer ring (should) align with the pointer on the timing cover at TDC 
(piston 'top dead center' on cylinder #1).  If you're using a 'regular' timing light, a half-inch off will be about 5-10 
degrees advanced or retarded, depending on which side of the pointer the line is on, engine speed and whether or not you 
disconnected the vacuum advance line (and sealed it off at the carburettor).  The only way to get a correct 
reading--that I know of--is to use an engine analyzer or advance meter.

Usually, timing too advanced causes detonation ('pinging') under load.  Too retarded causes poor acceleration and 
overheating.

Also, there's a (slim) chance the pulley/balancer has slipped on the rubber buffer between the inner and outer rings, so 
the timing mark may be incorrect.


bs


On 9/27/2010 4:15 AM, Paul Leeks wrote:
> Chaps
>
>
>
> A few months ago I was having trouble with poor acceleration and received
> loads of helpful advice (thank you all!) about the possible causes; vacuum
> leak, timing, poor electrics, valves, etc.
>
>
>
> One piece of advice was to retard the ignition and see what happens.  I did
> this ... and it has fixed it!  But now the timing mark on the flywheel is
> about half an inch out, but it runs normally.  I assume this doesn't matter?
>
>
>
> Also, I now have two supplementary questions which I will send on separate
> emails (to keep the 'threads' simple).
>
>
>
> Thanks to you all again
>
>
>
> Paul Leeks
>
> Lancashire
>
> 100/6 BN4
>
>
>


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Bob Spidell           San Jose, CA            bspidell at comcast.net

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