on 10/20/03 2:45 PM, Chuck Renner at crenner@dynalivery.com wrote:
> Let's try this again. I actually did send text the first time...
>
>> used for secondary-air injection. Since such air injection
>> is only required
>> during the engine's warm-up period, these pumps are switched using
>> electro-magnet couplings. Lower-priced blower pumps powered
>
> FWIW, on the Jaguar XK engines, the air pump runs constantly as well,
> but a valve is used to divert flow after a certain engine temp is
> reached. Whether the AIR is needed after warm up basically depends on
> the whether or not you have a working cat. Without a cat, the air will
> always help. With a cat, it's only needed until the cat lights off.
>
Huh, that seems inefficient. If you're going to go to the trouble of
installing a valve, why not a pump pulley clutch, to avoid pumping losses?
In the cheap, crude MG system, I'm not surprised, but you'd think Jaguar
could afford to do it properly.
--
Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the primer red one with chrome wires
|