1937 Buick Starter Solenoid

[Bobby Rodd]

When power is applied to the starter of my ‘37 Special, the starter just makes a whirling sound. I believe the problem is the solenoid. Could anyone please shed light on this issue? Also, if the problem is the solenoid, does anyone know where I can get my solenoid rebuilt or where I can buy a rebuilt solenoid? The starter works well.

Thank you

Bobby Rodd

[MCHinson]

There appear to be a few on ebay. Here is one: https://www.ebay.com/itm/1932-1953-Buick-Delco-Starter-Drive-NEW-Premium-USA-Made/173814070489?hash=item2878203cd9:g:7R0AAOSwj2Ra4V8R

[Bloo]

And to clarify a bit, MCHinson pointed you to a starter drive. it is usually the problem when the starter runs but does not turn the engine (not the solenoid).

 

 

[Bobby Rodd]

My thanks to MCHinson and Bloo.  Can I test the solenoid and starter drive to determine where the problem is?   
BRodd

[Bloo]

On a 1937 Buick there is a little relay on the back of the starter solenoid. It needs power and ground to pull in. It gets power from the autostart stuff, and ground from the voltage regulator (this is to prove the engine is not running before the starter kicks in).

 

Once that relay kicks in, it sends power to the starter solenoid, which pulls on the starter drive (via a linkage) and engages it to the flywheel.

 

Once the solenoid pulls completely in and gets to the end of it's travel, it bumps a copper disc against those 2 copper bolts in the back of the solenoid. Those 2 bolts and the copper disc form a switch. THAT SWITCH is what runs the starter motor.

 

So you see, if you step on the gas and the starter runs, the solenoid has ALREADY pulled in and knocked the copper disc against the 2 copper bolts. It is working.

 

The starter drive has a one-way clutch inside that can wear out, leading to a starter that runs away, rather than cranking the engine.

 

Once the starter drive is changed, there is an adjustment on the solenoid plunger you will need to make. The shop manual has details on that.

 

Edited October 1, 2019 by Bloo (see edit history)

[MCHinson]

If the starter spins but does not engage the flywheel, it would typically indicate the starter drive unless the flywheel ring gear is shot. I would pull the starter and take a peek at the flywheel ring gear. If it is OK, I would clean and lubricate or replace the starter drive. While you have the starter off of the car, you can apply 6 volts to the appropriate terminals and see if if it is spinning without the starter drive moving forward as needed to engage the ring gear. 

[Bobby Rodd]

Many thanks to you both. I’ve got much learning too do. I’m grateful to have guys like you to turn to. 
One last question... When I look at the points in the solenoid, they look pretty worn. How difficult is it to have them replaced?
BRodd

[Bloo]

Do you mean in the little relay or the copper bolts in the solenoid?

 

The little relay you can just clean the points if you need to. I would start by dragging paper wet with brake cleaner through them. Points gap and air gap is listed in the shop manual IIRC. Maybe a little file if they are really bad. Don't do much, they might have some precious metal on them you wouldn't want to scrape the last of it off.

 

If you mean the copper bolts, they get replaced when bad. When the bolt heads burn down enough, the copper disc no longer touches. Probably a solenoid rebuild kit from Bobs Automobilia or maybe Ebay? Or you could check with a local auto electric shop. The symptom when bad is "CLICK!" "CLICK!", basically the opposite of what you described. Sometimes they can just be turned around so the copper disc hits the "good" (unworn) side of the copper bolt head. That only works if someone didn't already do it 50 years ago.

Edited October 1, 2019 by Bloo (see edit history)