1972 LeSabre what causes starter housing to crack?

[Pete Phillips]

Just one thing after another on this 1972 LeSabre convertible. 350 V8. What causes the starter housing to crack in half like this? No, it was not dropped. This happened while it was on the car, being used.

Edited August 17, 2023 by Pete Phillips (see edit history)

[The 55er]

About ten years ago I tried starting my 1967 Riviera and that nose cone piece on the starter just blew apart with no prior warning or issues. Fortunately this happened at home in my driveway. I took it to my local auto electric shop and they said no problem, we have plenty of extra used pieces laying around. They rebuilt the starter and it's worked fine ever since. I'd be interested to know that caused it. 

[rocketraider]

Pete. You need an exorcist. Because this LeSabre is clearly possessed!

[old-tank]

Did it have a stabilizing strap from the motor to the engine block?  None will last long without it.

[NTX5467]

We saw that on many of the earlier GM diesel V-8s and some of the gas V-8s too, back in the 1980s and such.

 

Most common reason is that the starter bolts will get looser with age, unbeknownst to anybody.  The first thing that happens as the starter is used with the looser bolts is that the holes in the end housing get enlarged.  Digging into the Chevy parts book, I discovered that for some applications, they had a "starter brace" which went between a (already there) hole in the bottom front edge of the starter, to a corresponding hole in the cyl block.  Once installed, no further problems.  One for small blocks and one for big blocks.  Similar with the heat shields for the starters (that few people knew about, too).

 

When the starter bolts got loose on the GM diesel V-8s, they could also break the starter bolts off, leaving part of them in the block.  Those starters had OEM braces, too.

 

The brace is quite simple.  An L-shaped piece of metal, curved, with holes drilled in it for the bolts.  On some starters, a stud is screwed into the bottom hole for the brace to slide over and be secured.  On the Chevy V-8 350s, about 5" long or so, 454s shorter.

 

GM Group 2.077  72 350-455  Starter bolts w/extensioni    1941111

GM Group 2.077 67-72 All        Bracket, cranking motor mounting  1378215    Listed in the catalog section, no picture in illustrations

 

IF the starter was ever changed or removed, if it had an OEM bracket, it was probably not re-installed as "Not Needed" extra parts.

 

On so many engines, no braces were needed, for whatever reason.  Usually, as long as the valve cover gaskets didn't leak and the starter bolts stayed tight, no issues.  In reality, though, every starter with a mounting like that NEEDS a starter brace/bracket to keep things "right".

 

Hope this might help,

NTX5467

 

Edited August 17, 2023 by NTX5467 (see edit history)

[EmTee]

Check clearance between the starter pinion and ring gear.  Shim the starter so that the wire from a paper clip can just fit between the tip of the pinion and the root of the adjacent ring gear teeth when engaged.  Temporarily remove the solenoid to make measurement easier.  Insufficient clearance will break the housing.

 

Edited August 18, 2023 by EmTee (see edit history)

[Bloo]

There are at least 3 different ways to make that measurement, and if any aftermarket parts are involved, they won't agree with each other. Getting one of these block mounted starters to run quietly can give you gray hair, and might be impossible. If you adjust it the way @EmTee said, and make sure the bracket @old-tank and @NTX5467 mentioned is there, it won't break. If you are lucky, it might even be quiet. A little bit of blue loctite on the bolt threads wouldn't hurt either. The shims to set the drive gear clearance are a commonly available part. Any Oreilly, Autozone, Napa, etc. should have a packet of aftermarket shims.

 

Edited August 18, 2023 by Bloo (see edit history)

[Smartin]

Timing too far advanced

Edited August 18, 2023 by Smartin (see edit history)

[avgwarhawk]

I have seen this before.  Over-torqued bolts.  Fatigued metal. No support at the back of the starter.     

[60FlatTop]

Many years ago I saw a coworker break the nose off a starter. He had a chance to steal some antifreeze. Since it was free he put in 100% instead of 50/50. Some claimed the concentrated mixture "ate" through a gasket and water locked a cylinder.

I never got the whole story but I have some deep seated thoughts on using stolen stuff on cars. Maybe his example helped me morally.

 

I would probably pressure test the cooling system because of that memory.... and because I just replied to an overheating issue on the same car.

[Frank DuVal]

Flywheel rivets are loose. Wait, this wasn't a Corvair question. Oops.😁

 

I guess loose bolts on the flex plate would do it too. But there would be other symptoms/noise. There I go hearing a hoof noise and thinking Zebras here in North America.