Cadillac & LaSalle Club Discussion Forum

Cadillac & LaSalle Club Forums => Technical / Authenticity => Topic started by: Bill Balkie 24172 on November 30, 2021, 07:43:50 PM

Title: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: Bill Balkie 24172 on November 30, 2021, 07:43:50 PM
Hello,
   Lately I have noticed  after a long drive when I turn off the ignition and then restarting my starter turns over very slow but it always starts .  I do not think it is the alternator .  The Battery is two years old from Antique  Battery co. ( Jim's Battery ) my  cables are good and strong  . I put a voltmeter on the battery with all Accessories on and it reads 13.45 . This  only happen when the motor is hot but not every time .  My alternator has been rebuilt . The voltage regulated is original . I am thinking the Starter might be the problem .  That leads me to my next question . I have shopped starters  at all the popular stores .  I can't believe how inexpensive these starters are anywhere from 39.95 to maybe 70 dollars .  If I were to pull my starter and send it out to get rebuilt the cost would be about 150.00 at the local rebuilder (Jebco)   . Can anyone recommend a good quality starter supplier ?  I wouldn't  mind buying a new starter and sending my original out to get rebuilt and keeping it as a spare.  Any thoughts on these questions ?

       Bill
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: Dave Shepherd on November 30, 2021, 08:08:24 PM
Whatever  you do here make sure you convert it to a high torque  starter. This hot start issue was quite common  with  large GM engines back then. Starter heat shield can help also.
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: bcroe on November 30, 2021, 08:37:53 PM
My first starter check is remove the end cover and check the
brushes.  If any brushes are worn completely down, a very
inexpensive replacement set might be all that is needed. 

Here cars tend to cover long miles with infrequent use of the
starter. And I try to keep the engine in a state of tune, plus
pumping some gas first, for an almost instant start.  Even so
I do not expect a starter brush set to last 150,000 miles.  Your
driving routine could make this far less.  good luck, Bruce Roe
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: Bill Balkie 24172 on November 30, 2021, 08:56:10 PM
Quote from: bcroe on November 30, 2021, 08:37:53 PM
My first starter check is remove the end cover and check the
brushes.  If any brushes are worn completely down, a very
inexpensive replacement set might be all that is needed. 

Here cars tend to cover long miles with infrequent use of the
starter. And I try to keep the engine in a state of tune, plus
pumping some gas first, for an almost instant start.  Even so
I do not expect a starter brush set to last 150,000 miles.  Your
driving routine could make this far less.  good luck, Bruce Roe
Thank you Bruce for the good advice
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: Bill Balkie 24172 on November 30, 2021, 09:02:46 PM
Quote from: Dave Shepherd on November 30, 2021, 08:08:24 PM
Whatever  you do here make sure you convert it to a high torque  starter. This hot start issue was quite common  with  large GM engines back then. Starter heat shield can help also.

Hello Dave , These high torque Starters do they bolt up just like a stock starter .  What are the pros and cons if any . Thanks for your response .    Bill
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: 79 Eldorado on November 30, 2021, 10:09:22 PM
Quote from: bcroe on November 30, 2021, 08:37:53 PM
My first starter check is remove the end cover and check the
brushes.  If any brushes are worn completely down, a very
inexpensive replacement set might be all that is needed... 
Bruce Roe
Bruce,
I checked on Rockauto just to see what was available for our '79s and the only brushes they sell are literally just the brushes. I've changed brushes in an alternator but never gotten into a starter. Is there anything during the rear cover removal which is at risk of breaking or needs to be replaced each time the rear cover is removed?

I don't want to hijack the thread by mentioning our 1979 but I suspect nearly every starter GM used at least through the 80's was likely the same with respect to changing brushes/removing the rear cover.

Regarding hot start the other thing which came to mind for me was timing.

As Bill mentioned starters are not normally expensive but I can say that due to short lived replacements which friends had I try to only go with a very reputable brand like AC Delco, REMY and I do see BOSCH but the AC Delco and REMY are my go-to. I could be wrong but I assumed the original supplier to GM was REMY but likely was acquired at least once since.

Scott
Title: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: bcroe on November 30, 2021, 11:15:03 PM
Scott, As I recall it is possible to change the brushes mostly by just
removing the back cover, maybe undo the solenoid connection and
move the housing back a few inches over the armature.  Of course
this is not always the complete cure, but it often is.  A lot quicker
and cheaper than getting a new starter, and honestly I have found
that repairing my own stuff is a lot more reliable than buying an
Asian rebuild.  In recent years the car failures here are approaching
50% caused by recently purchased parts.  Bruce Roe
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: TJ Hopland on November 30, 2021, 11:21:51 PM
I just did the starter in my 73 this summer.   I think the repair kit was like around $15.   Brushes were completely gone in mine.  I can't believe that it started most of the time.   Wasn't a bad job.   I'm sure a proper shop could do a better job but I think what I did will last a lot longer than most of what you could buy new or rebuilt these days.   
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: Dave Shepherd on December 01, 2021, 07:51:56 AM
Bill, yes they bolt right up, the changes are all internal.
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: Big Fins on December 01, 2021, 08:00:53 AM
Be sure that you don't have the base timing too far advanced. It calls for 5o BTDC. If you advance it to 8o or 10o it will really make it hard to start. About 7o is all it will tolerate. Cold, there are no issues. Hot you get the 'turn, pause, turn, pause', then it will catch and start. Almost like a weak connection. Every one that I've ever had has done this. When you get into the lower compression years you can advance them a little further with no issues.

You can differentiate the high torque starter from the low torque starter by the distance of the bottom connection of the solenoid. The high torque unit has a 5/8" space in there with a brass sleeve and a longer screw. It would be easier to show in a picture. And yes, be sure you have the strap that goes from the back, really the forward section where the brush plate is, to the block. It helps take the strain off of the nose cone and also helps with grounding to the block.

Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: klinebau on December 01, 2021, 10:48:50 AM
By the book, initial timing for the 1970 Deville (472) is 7.5 degrees BTDC.  I am able to advance mine to 10 degrees with no issues.  Anything above that and the starter will do the woo...woo thing when hot.  YMMV.
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: "Cadillac Kid" Greg Surfas 15364 on December 01, 2021, 02:24:06 PM
This question of a "high torque" starter has come up often.  What the vendors such as rock auto have been selling as a high torque starter is actually the correct starter for cadillacs.  The difference between that and the "standard" starter is the length of the armature and field coils which results in a longer starter body. The standard starter is essentially a Chevrolet starter which is fine for a low compression motor or a vehicle that is not going to be used very much.
The length of the field coil section )(black part) of the correct Cadillac starter (often called High Torque) is 5-3/4". The other is about 3/4" shorter/ That 3/4"makes the difference.
Greg Surfas
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: George D. Mukalian CLC # 10047 on December 01, 2021, 03:57:15 PM
I had the same issue and used 0 grade battery cables and it solved the issue.

George
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: Bill Balkie 24172 on December 02, 2021, 06:42:38 AM
Thank you everyone for your input ,
      I am going to go with the high torque starter .  Thank you Greg, Dave   for your Rock Auto comment ( rock Auto High  torque Starter )   I will keep the old Starter and take everybody's  advice and replace the brushes and keep it as a Spare .

   Bill
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: 76eldo on December 02, 2021, 08:55:37 AM
I have always used Henry's Alternator in Trevose Pa.
The original starter on your low mileage car is probably built better than anything you can buy now.
Getting the original one rebuilt and reinstalled would be the way I would go.
I'd also double check the timing which could cause a hot start issue.
Take a good look at your connections on the cables at the starter too.
They are in a spot where heat, corrosion, and grease are a problem.

Usually new brushes and a clean up of the armature would solve any starting problems.
The field coils and the armature are subject to heat soak and the entire starter gets very hot when the engine is a full operating temp.

There are a few possibilities here. Timing and cable condition and connection are good places to start. 
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: Roger Zimmermann on December 02, 2021, 11:06:27 AM
The positive cable going from the battery to the starter relay is covered by a black isolation; he is located very near from the exhaust manifold. Inside the isolation the copper can get oxidized and have a high resistance when warm. A friend of mine had several break downs when the starter motor could not do his work with a warm engine. He discovered by accident that the wiring inside that black tube was very bad. Another thing to check!
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: V63 on December 03, 2021, 03:00:05 PM
For best insurance... Be sure a heat shield is in place on the solonoid. 2 ga or LARGER battery cables is ideal as well.
Title: Re: Sometimes Starter turns over a little slow . 1970 Cadillac 472
Post by: hirvine on April 07, 2022, 07:04:26 PM
Another option is to have Don at Gener-Nator rebuild one for you - he can do either low or high torque.  He is expensive, but the work is first rate and I have had better luck with his starters and alternators than what's currently being mass produced.