Jump to content

'51 Cadillac series 62 starter motor problem


polonus
 Share

Recommended Posts

When I turn the key in I can hear only the click and engine won't turn. I pulled out starter motor.

 

IMG-0098.jpg IMG-0102.jpg IMG-0104.jpg IMG-0103.jpg

 

Looks like it is an original, 6V starter, but this car is converted to 12V. However everything was working till now. Any idea how I should go about it repair/replacement? How and what to check? What 12V replacement part number would fit, if I need to make that change?

 

 Starter motor was connected to rest of the car with only one cable.

 

IMG-0110.jpg

 

This cable goes to that thing, located near battery, which, I think, is a kind of relay?

 

IMG-0108.jpg  IMG-0105.jpg  

 

What is that thing near battery? How do I test that?

Edited by polonus (see edit history)
Link to comment
Share on other sites

Can you post a picture showing that black jumper wire?  that does not look stock original.

 

Anyways, normally to bench test; You need to use a jumper wire from the big battery terminal, to a small one that could be marked S. That will make the solenoid pull on that linkage, so watch how you are holding it.  Also, hang on to it as the torque will make it fall off the bench, if it works.

 

If the solenoid does not move the linkage, then the gear won't extend out, and the gear won't turn, nor will the motor part spin.

 

To bypass the solenoid, you use the battery test cable to the big stud sticking out of the motor itself, where the copper strap is.   That will make the motor spin if using heavy battery jumper cables and a good ground to the housing near the bolt holes.

 

As far as which 12v Cad starter;  I am 99% sure Cad used the same size ring gear teeth from 49-53 on STANDARD shift cars,  53 would be the first 12v I think.  I have no idea if 54-up still used the same teeth, as I only know about standard flywheels, and the last standard was 53.  I just never worked with the A/T engines, so I don't know.

 

A old MoTors Shop manual WILL give starter info and starter numbers.  If you see that a 53 12v number is the same as the slightly newer A/T cars have, there is your answer.

 

If you can't find one, I can look to see if I have a book

 

 

Link to comment
Share on other sites

He, he....I was rethinking why it had a small jumper and was going to add some info, and I see that you just put up excellent pics just now :)

 

It is what I was thinking about.

 

When they did the 12v swap, they added that new fender-mount solenoid.  So it has TWO solenoids to test now.   When a second one is added, the small jumper HAS to be added to the original starter solenoid.

 

The new fender solenoid sends power to the big post on the old solenoid.  So, that post (on starter) is not powered if the car is NOT cranking.  On other systems, that post would have power, running or not running, key on or key off...always hot.

 

To test the New solenoid:  That small purple wire is activated by the cranking position on the keyswitch or starter "button" if that is what you have.   Jump the purple to the positive battery post, and that solenoid should clunk, and make a contact between both of the big cables on the new solenoid.  Test for power coming out of that solenoid as it goes clunk.  If that works, now bench test starter:

 

take one end of that small black jumper off.  Hook jumper battery cables to the case for ground, then hook the positive to the big post on the solenoid.  Nothing should happen, until you now use that black jumper to touch the big post which is now hot.  The starter solenoid should clunk and move the linkage, which moves the gear out, and it also sends power to the starter body to make the motor spin

 

..

Link to comment
Share on other sites

Some one added that Ford type solenoid up by the battery. The small wire on the Ford solenoid originally went to the small post on the starter. That little jumper wire from the small post to the big post on the starter was added at the same time to make the starter work with the new setup.

Edited by misterc9 (see edit history)
Link to comment
Share on other sites

14 minutes ago, F&J said:

To test the New solenoid:  That small purple wire is activated by the cranking position on the keyswitch or starter "button" if that is what you have.   Jump the purple to the positive battery post, and that solenoid should clunk, and make a contact between both of the big cables on the new solenoid.  Test for power coming out of that solenoid as it goes clunk.  If that works, now bench test starter:

 

take one end of that small black jumper off.  Hook jumper battery cables to the case for ground, then hook the positive to the big post on the solenoid.  Nothing should happen, until you now use that black jumper to touch the big post which is now hot.  The starter solenoid should clunk and move the linkage, which moves the gear out, and it also sends power to the starter body to make the motor spin

 

..

 Thanks a lot.

 

I will test it as soon as my son come back from work, with the cables in his car and let you know.

Link to comment
Share on other sites

15 minutes ago, misterc9 said:

Some one added that Ford type solenoid up by the battery. The small wire on the Ford solenoid originally went to the small post on the starter. That little jumper wire from the small post to the big post on the starter was added at the same time to make the starter work with the new setup.

Yes, I agree. 

 

As you already know, that twin solenoid setup is sometimes used on high compression race motors to make the system better.

 

but, I wonder why they did this on a stock vehicle?   One possibility?  maybe that old starter was acting up when hot?  and they added this "boost system"?

 

what is your opinion?

Link to comment
Share on other sites

OK, I was able to check it. Small, new solenoid works good.

 

On  starting motor when I connect power to either small terminal or big one, it moves that piston out, but it doesn't turn. When I connect power directly to starter motor, it does nothing. Looks like I need new starter motor. Do you know where to buy one? Any auto parts store should have it? Any modern replacements? Can I go with 12V starter and bypass that new, second solenoid?

Link to comment
Share on other sites

If that starter is definitely bad, and not just needing a new Cadillac 12v solenoid, you have 3 options that I can think of;

 

-get yours rebuilt to 12v specs; not cheap $

-find a used Cad 12v starter in good condition, if we can look up what years.  (could be good condition, or might be also bad)

-Call Tony at Ross Racing engines in Ohio.  He makes a modern mini-starter that has tons of power, for early Olds motors, and perhaps he makes one for the early Cadillac. 

 

They look the same, but Olds is on driver side, Cad is passenger side, so I don't know if he has one.  These are probably price comparable to a complete 12v rebuild of the original Cad 6v starter.

Link to comment
Share on other sites

39 minutes ago, polonus said:

Do you think repair kit from eBay may work? Something like that?  http://www.ebay.com/itm/Starter-Repair-Kit-Fits-1950-51-Cadillac-Delco-Remy-1107969-/351682363254

Not a bad price if it needs it.

 

If the starter armature is 'dragging", meaning it's armature body is starting to touch the field windings when things heat up...that might be bad bushings.  There is a nose bushing that you can feel for slop in the opening in the nose.  The other bushing is in the big front cover.

 

looking at your starter, compared to all the early Olds ones I deal with; yours is the same body design as 49-53 olds.  These have the sheetmetal band wrapped around the front and that is where you can see if the brushes are worn too much.  Too much is when the brushes get so short, that the spiral tension spring is now hitting the brush holder, and not pushing enough on the top of the brush.

 

Take off the band to see.

 

On 54-up olds starters, the body was changed and no longer has the strap or opening there.  Those need the end cover taken off to see.

 

Test what your problem is first.  If it seems like your starter motor spins ok when it was hot before, it could be just a burned out 6v solenoid.  If that is true, I'd only use a 12v Cad solenoid, if it will fit.  It would last longer if it fit.

Link to comment
Share on other sites

Thanks again. More pictures. Brushes have to be replaced for sure. Two brushes were gone, one felt outside, second was stuck inside. Two others where pretty much used up. There are also some loose, broken fiber? Cloth?

 

How do I clean and lubricate that thing?

 

IMG-0135.jpg IMG-0133.jpg IMG-0132.jpg IMG-0129.jpg IMG-0125.jpg IMG-0123.jpg IMG-0120.jpg IMG-0114.jpg IMG-0117.jpg IMG-0116.jpg

Edited by polonus (see edit history)
Link to comment
Share on other sites

If I am looking at the starter correctly, you are missing some of the brushes.  You might want to take off the end of the starter with the brushes to confirm  Either way you will need to take it off to install new brushes & springs.  The commutator does look good other than cleaning it up.

Link to comment
Share on other sites

Hard to imagine it worked with two gone!  I guess because it is 6v running at 12v...

 

disregard what I said about "spring hitting brush holder"  yours is not that type.  my mistake.

 

Armature dragging is when the big part of rotating armature actually looks like it was touching on one or more of those 4 rectangular iron parts that the field wires are wrapped around.  I can't see any touching, but take a good look to be sure.    Those iron blocks turn into magnets when powered...if the bushings get sloppy, they can touch.

 

Get some brushes...maybe a local parts store can find an interchange?  to a more modern car or tractor, whatever.  Some brushes fit lots of years...especially if it also fits chevys

 

then polish the copper segmented commutator that the brushes ride on.  Look to see if one segment has moved up, or down.  That is rare, though.  Clean with super fine scotchbrite pad or fine sandpaper.  Book says no sandpaper, but I've done it for years, but use very fine.

 

there should be a leather type washer at that commutator between it and bushing.  I think I see it?

 

as far as cleaning out the case and windings...  I reluctantly have used mineral spirits if absolutely needed, but be gentle with nylon brush/ or toothbrush. 

 

You may get lucky with getting this going again.  BUT, if the car only "clicked" and did not grunt the starter motor, then the brushes were not that issue.  Click, but nothing else like hearing the starter gear engage, points to a bad solenoid.  But yes, it still would need the brushes too

Link to comment
Share on other sites

I respect people trying to fix things.  Sure, if heading cross country, I'd get it remanufactured.

 

The tricky part is getting all 4 brushes to stay open while installing the armature.

 

at this point, with only 2 field coils doing the job of 4, those two may have been overheated and one could be shorted out.  time will tell.

But I still think the solenoid needs testing as soon as the starter gets back together.

 

if the solenoid does not work, you can still test the starter motor for spinning, by jumping to the copper strap connection.  The problem of this test, is that it won't be under a load.  So it may not have enough power to crank the engine If one or more field coils are damaged. 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...