shim the starter? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

cheatham · 11-07-2002, 12:03 AM

Last winter my starter was having some trouble turning the engine over. I would hit the ignition switch and the starter would whine, but not crank the engine (intermittenly, and especially when the engine is cold- but sometimes when warm). Well after a couple of trys it always turns the engine over. During the summer it did this very rarely and i forgot about it. Now it is getting cooler again and the problem has returned frequently.

Anyone know for sure what the problem is, I would like to know before shim the starter if that will help. I thought teeth might be broken, but the fact that it is 'almost' always happening when cold has made me suspect of that.

Any help is appreciated greatly.

JP

1971LT1SWBPOSI373 · 11-07-2002, 12:45 AM

The only way to really find out what is going on is to remove the flywheel cover (I assume you have an automatic transmission) and manually pull the starter gear out to engage the flywheel gear to see what is going on. I once came across a specific measurement for the gear mesh measurement, it was measured using a piece of wire, but I can't remember the size. Basically you were checking to make sure that the gears weren't bottoming out on each other....

*Piston* · 11-07-2002, 12:57 AM

Funny how certain times of the year bring on the same old problems.

(cold weather bendix problems)

What you want to look for when this happens, Open the hood then try to crank the engine over. Does the engine even spin? If the starter is spinning but the engine is not, chances are you have a bad bendix (starter). This is the one way clutch if you will.... It locks when reversed but spins freely when moved forward. The starter motor is turning but the bendix just free wheels when it should be locked.

When these go bad they tend to act worst when cold. After the engine has warmed a bit, the starter usually acts ok unless the bendix is just plain worn out completly. Then it will free wheel all day long and leave you stranded.

If you've had no trouble of grinding noises from the starter on normal starts, I'd suspect the positioning of the starter is ok. Double check your starter bolts though, make sure that starter is not moving around (seen that one happen before.. not pretty)

alta-aj · 11-07-2002, 01:25 AM

I had a similar problem and it turned out to be the battery was shot. It had enough voltage when tested with a voltmeter but collapsed when loaded. Also, as you know, battery efficiency deteriorates with temperature.

speeddemon · 11-07-2002, 02:42 AM

just a note: disconnect the battery before pulling out the bendix or the starter will try to turn over. You also want an1/8" of clearance between the armature( the shaft the bendix rides on) and the flywhel.

gangforward · 11-07-2002, 03:07 AM

Had the same trouble with my 67. It get's down to -40 in the winters here.. First issue was the bendix, I replaced the starter and it worked fine for a few weeks, then started up intermittently. I broke down and bought the Optima battery they use in Fire Trucks and Prudhoe Bay Alaska, the monster has never failed to start my truck no matter how cold it gets. Knock on wood, that was four years ago...

Good Luck!

67 Fleetside, 327, Glide.

1971LT1SWBPOSI373 · 11-07-2002, 12:04 PM

That's sounds like the correct measurement Speeddemon. I used a 1/8 inch drill bit and checked for a slip fit. Check the flywhel and your armature gear too, if the clearance was not correct then there may be some damage done if it's been doing this for a while. If your clearance is correct then your problem is somewhere else, probably the bendix itself.

cheatham · 11-07-2002, 01:08 PM

Thanks for all the info on this. Extra input always makes a job easier

BTW, it is a 3sp manual 1971LT1- guess i should make a sig, huh....

Thanks
JP

**StingRay** · 11-07-2002, 02:07 PM

On some years they were shimmed right from the factory. Most starter/Alternator shops will have the shims in stock. I just put em in one at a time till it got smooth and quiet.

1971LT1SWBPOSI373 · 11-07-2002, 02:15 PM

Same still applies Cheatham. You still want to do the same thing, pull the cover, check the measurements and inspect the gears.

adamls · 11-07-2002, 02:19 PM

Try measuring the voltage at the starter when cranking it. It should have at least 12 volts. I read about this problem in one of my bathroom mags a month ago or so. The guy only had 9 volts going to the starter because of a bad battery and wires.

11-07-2002, 12:03 AM	#1
cheatham I need a brake! Join Date: Jul 2002 Location: Nashville, TN Posts: 474	shim the starter? Last winter my starter was having some trouble turning the engine over. I would hit the ignition switch and the starter would whine, but not crank the engine (intermittenly, and especially when the engine is cold- but sometimes when warm). Well after a couple of trys it always turns the engine over. During the summer it did this very rarely and i forgot about it. Now it is getting cooler again and the problem has returned frequently. Anyone know for sure what the problem is, I would like to know before shim the starter if that will help. I thought teeth might be broken, but the fact that it is 'almost' always happening when cold has made me suspect of that. Any help is appreciated greatly. JP

11-07-2002, 12:45 AM	#2
1971LT1SWBPOSI373 Registered User Join Date: Mar 2002 Location: Springfield, VA Posts: 460	The only way to really find out what is going on is to remove the flywheel cover (I assume you have an automatic transmission) and manually pull the starter gear out to engage the flywheel gear to see what is going on. I once came across a specific measurement for the gear mesh measurement, it was measured using a piece of wire, but I can't remember the size. Basically you were checking to make sure that the gears weren't bottoming out on each other.... __________________ 1971 Shortbed 350/350 w/ Posi-traction 3:73's 1996 Chevy Silverado TJ in Springfield, Virginia Likes old Chevy trucks Drinks Miller MGD

11-07-2002, 02:42 AM	#5
speeddemon Registered User Join Date: May 2002 Location: lexington,South Carolina Posts: 158	just a note: disconnect the battery before pulling out the bendix or the starter will try to turn over. You also want an1/8" of clearance between the armature( the shaft the bendix rides on) and the flywhel. __________________ 69-C10 LWB 71- fleetside shortbed It's a shame stupidity isn't painful Never play leapfrog with a unicorn

11-07-2002, 12:04 PM	#7
1971LT1SWBPOSI373 Registered User Join Date: Mar 2002 Location: Springfield, VA Posts: 460	That's sounds like the correct measurement Speeddemon. I used a 1/8 inch drill bit and checked for a slip fit. Check the flywhel and your armature gear too, if the clearance was not correct then there may be some damage done if it's been doing this for a while. If your clearance is correct then your problem is somewhere else, probably the bendix itself. __________________ 1971 Shortbed 350/350 w/ Posi-traction 3:73's 1996 Chevy Silverado TJ in Springfield, Virginia Likes old Chevy trucks Drinks Miller MGD

11-07-2002, 02:07 PM	#9
StingRay Senior Member Join Date: Mar 2000 Location: Saskatoon,SK,Canada Posts: 2,476	On some years they were shimmed right from the factory. Most starter/Alternator shops will have the shims in stock. I just put em in one at a time till it got smooth and quiet. __________________ Saskatoon, Saskatchewan Canada

11-07-2002, 12:57 AM	#3
Piston Account Suspended Join Date: Oct 2002 Location: Olathe, KS Posts: 2,301	Funny how certain times of the year bring on the same old problems. (cold weather bendix problems) What you want to look for when this happens, Open the hood then try to crank the engine over. Does the engine even spin? If the starter is spinning but the engine is not, chances are you have a bad bendix (starter). This is the one way clutch if you will.... It locks when reversed but spins freely when moved forward. The starter motor is turning but the bendix just free wheels when it should be locked. When these go bad they tend to act worst when cold. After the engine has warmed a bit, the starter usually acts ok unless the bendix is just plain worn out completly. Then it will free wheel all day long and leave you stranded. If you've had no trouble of grinding noises from the starter on normal starts, I'd suspect the positioning of the starter is ok. Double check your starter bolts though, make sure that starter is not moving around (seen that one happen before.. not pretty)

11-07-2002, 01:25 AM	#4
alta-aj Registered User Join Date: Aug 2001 Location: Qualicum Beach, B.C>, Canada Posts: 117	I had a similar problem and it turned out to be the battery was shot. It had enough voltage when tested with a voltmeter but collapsed when loaded. Also, as you know, battery efficiency deteriorates with temperature.

11-07-2002, 03:07 AM	#6
gangforward Hootis is as Hootis does... Join Date: Nov 2002 Location: Southern Georgia Posts: 500	Had the same trouble with my 67. It get's down to -40 in the winters here.. First issue was the bendix, I replaced the starter and it worked fine for a few weeks, then started up intermittently. I broke down and bought the Optima battery they use in Fire Trucks and Prudhoe Bay Alaska, the monster has never failed to start my truck no matter how cold it gets. Knock on wood, that was four years ago... Good Luck! 67 Fleetside, 327, Glide.

11-07-2002, 01:08 PM	#8
cheatham I need a brake! Join Date: Jul 2002 Location: Nashville, TN Posts: 474	Thanks for all the info on this. Extra input always makes a job easier BTW, it is a 3sp manual 1971LT1- guess i should make a sig, huh.... Thanks JP

11-07-2002, 02:15 PM	#10
1971LT1SWBPOSI373 Registered User Join Date: Mar 2002 Location: Springfield, VA Posts: 460	Same still applies Cheatham. You still want to do the same thing, pull the cover, check the measurements and inspect the gears. __________________ 1971 Shortbed 350/350 w/ Posi-traction 3:73's 1996 Chevy Silverado TJ in Springfield, Virginia Likes old Chevy trucks Drinks Miller MGD

11-07-2002, 02:19 PM	#11
adamls Gotta Startem Early Join Date: Oct 2001 Location: Amarillo, TX, USA Posts: 364	Try measuring the voltage at the starter when cranking it. It should have at least 12 volts. I read about this problem in one of my bathroom mags a month ago or so. The guy only had 9 volts going to the starter because of a bad battery and wires. __________________ 67 SWB In Progress, one piece at a time, maybe 3 years I will be finished



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.