Ignition timing

Discuss mechanical problems here.
Forum rules
By using this site, you agree to our rules. Please see: Terms of Use
Post Reply
markandsuefoss
Minor Friendly
Posts: 34
Joined: Sun Dec 27, 2015 6:49 pm
MMOC Member: No

Ignition timing

Post by markandsuefoss »

I have a 1971 Traveller and have a question about ignition timing. I see the Haynes manual recommends 3 or 5 degrees BTDC, but I have been recommended 8. Which is correct?

Thanks.
simmitc
Moderator
Moderator
Posts: 4920
Joined: Thu Apr 15, 2004 9:43 am
Location: Essex
MMOC Member: Yes

Re: Ignition timing

Post by simmitc »

The original settings were for petrol that was very different from that of today. For a 1098 engine, 3 degrees is a good starting point for the static timing - the engine will run well. You then need to very slowly advance the timing until you just start to hear pinking whne under load; and then retard the timing slightly until the pinking stops.
philthehill
Minor Maniac
Posts: 11585
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Ignition timing

Post by philthehill »

The timing as quoted in the BMC manual is 3 degrees BTDC static and 6 degrees BTDC @ 600rpm with a strobe for a 10MA engine (1098cc with a 25D4 distributer)
Because of the difference in fuels from when the Minor was new - you should set the timing by setting to the basic setting and then advancing the ignition until the engine starts to pink under load and then retard the ignition until the pinking disappears.
No two engines are the same and the timing needs to be set for individual engines.

markandsuefoss
Minor Friendly
Posts: 34
Joined: Sun Dec 27, 2015 6:49 pm
MMOC Member: No

Re: Ignition timing

Post by markandsuefoss »

Hi both,
Thanks very much that explains the different settings people are using.
JOWETTJAVELIN
Minor Legend
Posts: 2775
Joined: Mon Dec 12, 2011 7:20 pm
Location: LANCASHIRE (paradise)
MMOC Member: Yes

Re: Ignition timing

Post by JOWETTJAVELIN »

But, if it then struggles against the starter motor you've gone a bit too far!
Post Reply