49 Custom 8 starter solenoid

[onthehunt]

Looks like some water got into the starter solenoid on my 22nd series custom 8. (previous owner pressure washed the engine...not a good idea!!).  The custom 8 uses the high torque Autolite starter and a unique solenoid that isn't shared with junior cars. 

 

Does anyone know the testing procedure for the coil that retracts the big plunger for the bendix?  Mine intermittently works but I suspect it has weak windings. 

 

Are there any solenoids that interchange with the Packard unit?  I've seen a number of Chrysler solenoids that look identical but the relay box is oriented a little differently. Also 51-52 Packard solenoids look similar, and I wonder if I could adapt one?

 

Kanter lists an exchange service for the correct unit, but these are so hard to find I'd like to get something that can be replaced more easily if it fails in the future...

 

 

Edited October 11, 2018 by onthehunt (see edit history)

[HH56]

Far as I know there is no other Autolite solenoid directly interchangeable.  Possibly the 6v Delco could be made to work if you can find one but don't know that for fact.  I believe Max Merritt also has the solenoids at exchange -- at a price.  Hollander has the same type Autolite stater and solenoid assy interchangeable 46 - 52 on the senior engines and according to Hollander a Delco starter might have been a replacement. 

 

Here is a bit from an old Motors Manual that gives a bit on how to test the solenoids.  It could be water caused the relay contacts to oxidize or the plunger or linkage has some rust which is causing a binding issue.   I have also ran into solenoids where a long cranking time caused the plastic bobbin the solenoid coils are wound on to expand and bind the plunger.  Because the solenoid series coil goes thru the motor to find ground it relies on good conductivity thru the  motor windings for its pull in strength so the motor connections,  brushes,  etc also need to be in good condition.

[HH56]

One other thing.  The symptom you mentioned can be the solenoid as the problem but if stock the Customs that used that solenoid will have a safety circuit to prevent the starter from operating once the engine is running.  That was just in case the starter switch was out of adjustment or for some reason the switch did not disconnect from the accelerator linkage to prevent operation at full throttle.  With the circuit, the small relay in the enclosure that operates the solenoid gets a ground thru the generator windings.   If there are brush or generator problems it is possible a good solid ground is absent at times so relay will not pull in and nothing happens when you try to start the car.  That was an intermittent but known problem and Packard issued instructions on how to bypass the safety circuit on cars where the owner wanted it done.  Basically it involved disconnecting the ground side of the relay from the ARM terminal at the voltage regulator and connecting it to a solid ground.

Edited October 12, 2018 by HH56 (see edit history)

[onthehunt]

Thanks for posting! Its hard to explain my results, but basically I removed the relay assembly from the solenoid and tested only the solenoid coil.  If I understand right it has 2 windings - one for pulling the plunger in and another to hold it. The hold coil is powered when the starter motor runs, and the pull-in coil gets power when the starter switch sends voltage to the relay points, closing the points.

 

When I put power to only the wire for the pull-in winding, it hums and barely moves the plunger.  If I put 6V across both the wires for the pull-in and hold coils, it works every time. 

 

Looking closer I found the relay also has a broken wire on the winding, so it looks like  the whole unit is shot. Time to bite the bullet and buy a rebuilt one I guess. 

[HH56]

Depending on where the break is it might be possible to repair the wire but hard to say not being able to see it.  In the drawing above the coil labeled shunt is kind of a hold coil.  It helps but does not have the power to pull the plunger and move the pinion by itself.  The coil labeled series does the hard work.  It is the heavy wire that gets ground thru the motor windings and gives a strong pull to get the plunger to move.  As soon as the plunger moves enough to close the copper disc and contacts to start the motor, the closing of those contacts results in voltage from the relay thru the series coil being bypassed around the coil so it is out of the circuit leaving the shunt coil to hold the plunger in.

[onthehunt]

I just picked up a cheap "NOS" Chrysler autolite unit for parts...am going to poke around on it to get a better idea of how these work.

 

[onthehunt]

Thanks also for the note about grounding through the starter windings...That's an important point. 

The Chrysler solenoid arrived today and it bolts up and seems to work perfectly! Only change is that it requires a longer copper strap from the relay terminal to the starter, as the Chrysler unit is clocked differently and sits sideways vs. the Packard's straight up and down orientation. 

Will post pics when I get it together.  The best part was it only cost $63.

 

 

[Joe Block]

I have a few super 8 starters. I check for a working selnoid