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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: Bitzer! on June 21, 2013, 10:51:38 am

Title: Flexiplate
Post by: Bitzer! on June 21, 2013, 10:51:38 am
Morning all, thought I had all issues covered but another one comes to light.
My old starter destroyed the nose cone and the teeth on the flexiplate, thought I'd shimmed it wrongly. New flexiplate and starter fitted and I can now see the problem.
The cog in the starter won't fire across the flexiplate far enough. I've done the screwdriver trick and it physically won't go more than 1/4 across.
Anyone had this before?

Cheers

Andy
Title: Re: Flexiplate
Post by: 80Chevy4x4 on June 21, 2013, 08:36:35 pm
Go get some different thinkness starter shims from the parts store and try the smallest one first.....that sounds like it could be the problem.
Title: Re: Flexiplate
Post by: Bitzer! on June 22, 2013, 02:14:55 pm
It's cooking my head! I don't think it's a shimming issue, I've slackened off the starter bolts and moved the nose cog out with a screw driver but it goes no where near far enough across the teeth on the flexiplate??

Andy
Title: Re: Flexiplate
Post by: 74 C-10 Shorty on June 22, 2013, 02:24:57 pm
Shims space out the gear from the plate not move it back, but I've never yet seen a GM starter gear move out far enough to engage the whole amount of the gear on the flexplate or flywheel.
Title: Re: Flexiplate
Post by: 80Chevy4x4 on June 22, 2013, 02:32:04 pm
Ok here is one that a lot of people overlook or never think of........take a prybar and see how play the crankshaft has.....see if it moves front to back and back to front...it doesn't happen a lot but i have seen problems where the thrust bearing is worn more than normal and it can create some problems.....
Title: Re: Flexiplate
Post by: Bitzer! on June 22, 2013, 04:06:19 pm
Fair point fella, I'll check that tomorrow (UK time!) it's doubtful as the engine was fully rebuilt before I put it in and it's done next to zero miles.
This truck has had starter issues from the time I bought it, I fitted the new flexiplate the same way the old one came off. Is there any chance the old one was fitted the wrong way round and caused all the problems?
I serviced the auto box and noticed the poor workmanship where it had previously been removed so anything is possible I guess. The balance weight on the flexiplate is on the gearbox side not the engine side, not sure if anyone could clarify from that?

Help!!!!!

Cheers

Any

Title: Re: Flexiplate
Post by: Bitzer! on June 22, 2013, 05:31:37 pm
Shims space out the gear from the plate not move it back, but I've never yet seen a GM starter gear move out far enough to engage the whole amount of the gear on the flexplate or flywheel.

Sorry bud, missed this!

The starter cog meshes 2-3mm. That's as far as it reaches. I've been told I should have 1/2 to 2/3 but NOT all the way across.

Andy
Title: Re: Flexiplate
Post by: 74 C-10 Shorty on June 22, 2013, 06:35:26 pm
I don't remember ever having one that went more than half, probably even less?, but never actually measured them to be honest..
Title: Re: Flexiplate
Post by: Bitzer! on June 24, 2013, 02:23:35 am
Still having issues ggrrrr

Can anyone clarify if the weight on the flexiplate should be on the engine side or gearbox side?

As the PO's have had their fingers in it and the workmanship was poor is there a chance they've replaced it the wrong way and I've copied their work?

Cheers

Andy
Title: Re: Flexiplate
Post by: 80Chevy4x4 on June 24, 2013, 04:37:13 am
one thing to check......double check the starter making sure it is the right one....one time when i was working at the dealership we did end up getting a starter from an aftermarket(the customer bought it) and the nose cone was a fraction to short...it was manufactured wrong.......hope it helps.
Title: Re: Flexiplate
Post by: Bitzer! on June 24, 2013, 06:57:21 am
I think I've covered that one too. I took my chewed up hi-torque out and replaced it with a mini. That didn't even reach the flexi! Took that back and went through all the starters they had in stock (!!) and walked out with the same as the high torque one I had to start with.

I'm starting to think a PO got the flexiplate wrong and I've copied his mistake.
Looks like I'll drop the box out and flip the plate just to see if it makes a difference.

Gutted as the truck was due to go to its first show at the weekend!

Cheers

Andy
Title: Re: Flexiplate
Post by: Bitzer! on June 24, 2013, 04:18:17 pm
Just been out, crawled under the truck and Huston I have a problem!
Schoolboy error - the new flexiplate was fitted same way the old one came off. Weight on g/box side etc. looks like it should be the other way round so this weekend it's drop the box spin flexiplate that will hopefully give me the 5-6mm I need for the cogs to mesh nicely!

Cheers for all the suggestions, I'llet you know what I find!

Andy
Title: Re: Flexiplate
Post by: 74 C-10 Shorty on June 24, 2013, 06:07:42 pm
Yep, weight goes to towards the block that'll probably cure the issue..
Title: Re: Flexiplate
Post by: Bitzer! on June 24, 2013, 07:05:51 pm
That could well explain the PO's issues amongst others when I bought it. As I never took it off I had no reason to check it until I recently changed the flexiplate as the starter chewed it out.
Live and learn!
Andy
Title: Re: Flexiplate
Post by: Bitzer! on June 27, 2013, 03:56:58 am
Quick update - dropped the box down last night. Boy are they heavy!!
Swapped flexiplate round and checked the starter cog mesh. Spot on! Just have to find the time and energy to refit the box and that should be all problems solved.
Mad to think the old one lasted as long as it did the wrong way round!

Take care y'all

Andy
Title: Re: Flexiplate
Post by: 74 C-10 Shorty on June 27, 2013, 08:32:03 am
Glad to hear problem solved..
Title: Re: Flexiplate
Post by: Bitzer! on July 04, 2013, 03:49:45 am
This problem is now fully resolved!!

Dropped the box out (boy are they heavy!) spun plate, checked starter, box back in with filter change and superb. It's never sounded better when it turns over and starts. Actually sounds smooth and engages properly with the flexiplate. One happy bunny!

Cheers for all the suggestions, I should really question the previous owners work by now. Even the filter in the box had the washers etc on the bolt wrongly placed to the filter would wobble about and was hitting the bottom of the pan!

Onto the next problem.............new thread for that!