grinding when starting

[mdj]

I have a 88 chevy k1500 lifted truck. Everytime i start it it grinds. We have put three starters on it and shimmed the last one and it went out again. Dont see nothing wrong with the fly wheel but do you think if i put a new one on it will solve my problem thanks
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[speedygonzales]

There should be no grinding noise EVER. The gap between the starter gear and the flexplate gear should be the thickness of a paper clip. Here's a diagram.
paper clip method

The starter like our engines come with can not be measured with a paper clip because they have a nose cone that supports the bendix gear. Shown here
nose cone type starter

The paper clip method can only be done on a "denso type" starter shown here
denso type starter

I switched over to a Denso type starter years ago. When you use the paper clip method to shim them, it only has to be done once and you are done. If you keep the nose cone type starters, the method to shim is time consuming and you use your ears to determine if it has been done correctly. Not the most subjective way to do things.

Start with the starter by it self with no shims. Bolt it in place and crank the engine. If there is no noise, it is more than likely good to go. If it makes a high pitch whine when cranking (not after the engine fires). The starter is too far away from the flexplate gear and needs to be shimmed on the bolt furthest away from the flexplate only. NOT BOTH BOLTS.

If the starter makes a noise after the engine fires up, the starter is too close to the flexplate gear and needs to be shimmed away. This is when you can either shim all the way across both bolts with shim strips like is pictured with the "denso" starter or the bolt closest to the flexplate can be shimmed by itself. It is obviously easier to shim with a complete strip. However if the inboard bolt is shimmed by itself, greater clearance can be gained then doing both bolts at one time.

Use this link to find this information
http://www.google.com/url?sa=t&rct=j...53371865,d.eWU

You can see the "sound" method is not very accurate and more than likely will have to be repeated until it is right. That is why I only use denso type starters without the nose cone. Another reason I stopped using nose cone types are misfires. If your ignition is poor and a cylinder doesn't fire right away then suddenly fires, the kick back can. And in my case did, blow the nose cone right off the starter.

Also care must be taken in which flexplate and starter is used for replacement. There are 2 flexplates available for our engines that are either 168 or 153 that will fit but only one is the right one to use.

Another problem is the flexplate will crack at the crank shaft where it mounts and can cause problems. Usually a lot of noise accompanies that problem when driving.

Always check all the teeth on the flexplate when ever doing work on the starter.

[Newguy71]

Speedy, I didn't catch this in your message (which was very good and was explained very well) but on my 1971 GM 2500 pickup my starter makes a god awful grinding and clunking noise when it's trying to start. Once I'm up and running no noise what so ever. I put 3mm worth of shims and it helped but only minimally. I took them off and it's back to sounding terrible. Also, sometimes the street will not disengage from the flywheel. Any thoughts? I tested the starter and it passes the test but I'm thinking that it's a bad starter. BTW it's one of the big starters, original model I'm guessing.

[Mr_Rich]

I replaced my orig. starter with a mini starter (in my K1500) so long ago I can't even remember now. When my orig. starter failed one thing I did was remove the solenoid and install the starter without it for testing purposes. I operated the Bendix by hand to verify it was smoothly engaging the flexplate. Shim accordingly until you get a smooth engagement. The mini gear reduction starters cost more but I've found them to be super reliable and trouble-free in my experience. You can give that a thought or two...

[Newguy71]

Thank you. Where do you pick up those mini starters? Internet?

[Newguy71]

Did you go with an aftermarket mini or a GM mini? I read where someone recommended using one from a 2005 silverado 2500.

[Mr_Rich]

I'm pretty sure I went with GM. It's been installed so long I forgot. My '89 has ~280K miles so that represents a lot of time. I re-used this mini-starter when I swapped this engine out four years ago. My original starters seemed to fail on me every couple of years and they seemed to wait to fail until winter. I hated dealing with those twenty plus pound units that eventually failed.
3rd gen Camaros/ Firebirds used a mini starter so think late 80's, early 90's. You have to use shorter bolts and you need the staggered hole unit for the larger flexplate.

[Mr_Rich]

The sound is much different too. It kind of sounds like a Chrysler on starting if you remember that sound from the early cars.

[Newguy71]

I'm 24, I was most likely conceived in one of those I got a Napa rebuilt original, bolted up with new bolts and no problems but it is still early in the game. They had a mini one but it was bolted straight across and I didn't no I had the option to use staggered or straight learning the same lesson for the millionth time, slow down and really analyze what I'm doing. Thanks for us info, I'll go with the micro starter next time I need a new one!