Re: Stewart's 1955 Packard 400

Posted by HH56 On 2023/8/23 18:36:08

Not sure the solenoid running direct from the ign sw and having too many amps was what was causing the burnout issue. The solenoid should determine the max it needs and take no more even if fed directly from the battery. If the voltage is low or the wire connecting the ign sw to the solenoid is not large enough or a connection is bad and unable to supply the required amps or voltage for solenoid to pull in then that would be an issue and could cause the solenoid to fail.

The relay in this drawing is only doing one thing and that is if the manual switch is on then it activates when the pressure switch closes and brings in the solenoid when the trans is in 4th gear and no other. It is providing the same power as if the solenoid were connected directly to the ign sw. Main difference is if solenoid was connected directly to ign sw, unless it had a manual switch it would be on anytime the ign sw was on and could bring in the solenoid at 1,2,3 and 4th gear.

I don't really know what is happening in the trans to limit when it is active -- maybe a governor or something like that -- but if solenoid was on all the time seems like the clutch would also be engaged all the time.