starters-when to use shims?

[Sunliner]

Ok, may be a dumb question, but how do I know if I need starter shims?

I'm having a problem with my Blazer being hard to start, but only every now and then. I was first thinking it was an electrical prob (maybe it is) because it sounds like the starter's not getting enough juice when it does act up. Replaced the starter and battery and it still acts up sometimes. I've been checking the alternator and battery periodically and they look good. Cables look good, grounds are tight.

The only thing I can figure is this-and I'm no expert...about a year ago, I had a new transmission put in. I dont' know if they remove the starter to do this, but I did note that when I replaced the old starter, there were no shims, so I didn't put any in with the new starter. So...maybe it's not engaging well? Or if it was a shimming issue would it act up more regularly?

[85sskid]

I'm not an expert on when to use shims either but I think if it needed the shims, it would be very constant that it'd be hard to start. I think you'd get more of a gear grind rather than a hard start. I do have a similar problem that sounds like yours on my Monte Carlo. I know for a fact on mine, it is the piston rings are TOO worn out and has too much blow-by. Spark plugs get soaked in oil and will make it feel like the alternator has weak starts. Do you know if your rings are originals? How many miles on the truck?

[Sunliner]

original rings. got just short of 150,000 miles on the truck

[j cAT]

Originally Posted by Sunliner

original rings. got just short of 150,000 miles on the truck

the starter connections need be clean and tight..this includes the starter nut that has no wires to it...

then the battery wires both pos/neg need be cleaned and checked...this includes the engine ground points ...remember you need good grounds as well as the positive feed to get a good high current flow to the starter... corroded connectors and green wires at the battery means you need new wires/connectors..

get the battery load tested..

you need to use shims when you don't have a 1/8inch space beteen the flywheel and , starter gear teeth...this is with the solenoid only energized [no pwr to starter motor].....


flywheel teeth may have been damaged , when they screwed with the tranny....inspect all teeth use chalk to ensure all are inspected...