Re: Decent small 12v ignition coil
Posted by Stuart on August 8, 2018, 9:14 pm, in reply to "Re: Decent small 12v ignition coil"
Hi Mark, |
>I got one of those from Hitchcocks, much smaller than the Lucas equivalent
Errrm ... your picture shows a Lucas MA12 or MA6 (or pattern) coil on the left and a PVL pattern of a Lucas 17M12, 17M6 or 17M4 on the right; the Lucas 17Mnn coils superseded the MAnn coils in 1969 or 1970. As the current user of the "Lucas" name/trademarks/packaging/etc., Wassell makes new ones of both (emblazoned with "Genuine Lucas" or some such bolleaux).
Ime, far-and-away the most-common cause of Lucas coil failure is mounting them rigidly on something that vibrates. Even Triumph and BSA had worked that out for the triples in 1968 and then the oif twins in 1970.
The second-most-common cause of failure is allowing people who should be restricted to Bob The Builder tool kits unsupervised access to proper tools and the fasteners of clamps like the one around the PVL coil ...
If the PVL coil is supposed to be a replacement for the coil on the left, the biggest favour you can do the PVL coil is use the clamp from the bigger coil, put a layer of rubber (cut from an old inner tube?) between the coil and the clamp, tighten the screw and nut through the circular holes in the clamp with thumb-'n'-forefinger only on the screwdriver, bolt the clamp through the slotted holes with thick rubber washers between the clamp and whatever you're bolting it to ... don't let anything else on the bike touch the coil case ... and use the clamp around the PVL coil as a small flower-pot holder or similar ...
>apparently better quality.
Certainly Lucas constructed the 17Mnn coils with hard separation between the LT and HT windings, filling the coil with oil for cooling. So only if anything on the bike wears through the case, the oil runs out and the coil is donald.
Otoh, certainly the PVL's I know of have been filled with pitch. Only this keeps the LT and HT windings apart. as long as the coil doesn't get hot enough to melt it ...