> David Macedonia wrote:
>
>> Listers,
>>
>> I'm stumped. In trying to set the timing of my '66B (18GB engine, which
>> I just got started for the first time in 9 years!), I found that I have
>> to rotate the distributor almost as far as it can go counter-clockwise
>> (to the point where the vacuum advance hits the oil pressure gauge line)
>> and have the timing vernier rotated fully clockwise before I can get the
>> timing to be approximately 15 deg. BTDC @ 800 rpm. It's been years since
>> I installed the timing chain, but could it be possible that I'm off by a
>> tooth or two in the relationship between the timing gears? Or, is there
>> some other explanation? My concern is based on pictures of similar cars
>> that have their distributors oriented such that the vacuum advance is
>> below or just to the right of the heater control valve. Or, am I just
>> missing something obvious?
>>
>> It turns out that I have a leak in my radiator, so I'll probably have to
>> remove it. So, if I need to work on the timing chain, this will be as
>> good a time as any.
>
> Why would the timing of the cam and distributor be out? If they have
> not been removed, they can't have changed. The timing chain cannot
> jump a tooth. It's possible the distributor drive gear is installed
> wrong, but if it is, it always was, unless it has been removed and
> reinstalled wrong. These things don't change unless somebody changes
> them. Are you checking the static timing? The timing point is where
> the points break, when they first open. If you're using a timing
> light, I'm pretty sure the vac advance must be disconnected and the
> timing set at a low idle, so the centrifugal advance isn't operating.
>
> The timing chain is either broken or working fine; there's no in
> between. It's not something that gets out of adjustment.
>
> -Rock http://www.rocky-frisco.com
If you've had the distributor out recently, the gear could have pulled up
when the distributor was out, and it may or may not have dropped back in
the proper teeth. That would offset it somewhat. There are a few ways to
correct this situation. You can re-set the distributor drive to
compensate. You can rotate the wires one spot on the cap, and then turn
the distributor 90 degrees to compensate. Just make sure you rotate them
the right way, or you will have real interference on the block and cap.
Phil Bates
'67 MGB
'58 MGA
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