turbodarryl

iTrader: (4)

Hey guys, i just wired up my starter on my conversion project, when i tried to see if everything matched up… starter/flexplate by spinning it over, the starter hits the flexplate instead of engaging with it, i don't know of anyone needing to shim a ls1 starter and this looks to be too much to shim, its a 98 LS1 with a Advance adapters flexplate part # 712500A, stock ls1 starter, any advice?

gofastwclass

iTrader: (2)

I'm not saying it isn't possible but I've never heard of a need to shim a Gen III / IV engine starter.

Is the battery fully charged? A low battery may not allow the starter to fully engage.

Are you sure the starter is good?

I'm assuming the donor vehicle was wrecked with these:

Is the starter seated properly against the block (not bound against something) or have a cracked housing?

Are the bolt holes / threads damaged on the block?

Are the bolts straight?

turbodarryl

iTrader: (4)

this engine was removed from my daily driver 6spd 98 z28 a few weeks ago, it never had a starting problem , it turned over with no noise or issues, i just thought of something, are the starters from 6 spd's to automatics the same?, and yes i have a fully cgarged yellow top, starter fully seated, almost look like the flexplate diameter is too large.

gofastwclass

iTrader: (2)

I would remove the flexplate and compare it to the flywheel from the original setup. If the diameter is too large, not a lot you can do beyond return the flexplate.

I always use GM flexplates that come with the engines or get them from the salvage yard. I've only used one aftermarket flexplate and it was a TCI SFI approved ($$$) which went on a car I was building for someone else because that is what he wanted.

turbodarryl

iTrader: (4)

well this is what i found today, tried the same thing first by just spinning the starter, Same result, so i turned the flexplate 90* and wola it turned the eng over but every time it got to the same problem section it started making the I NEED A SHIM noise very loud then normal then noisy letting me know that my flexplate is big time out of round.

Briou

iTrader: (1)

Man that is pretty crazy that the flex plate could be that far out of round....but I'm glad you figured out the problem...

turbodarryl

iTrader: (4)

yes it is crazy, this is the same engine/starter combo that had zero problems with the 6 speed manual flywheel, flexplate slid on with no problems, then this problem started.

Pop N Wood

iTrader: (1)

Sounds like you need a new flexplate, but FWIW my MSD starter came with simming instructions and shims, so not totally unheard of for an LS motor to need a starter shim.

1bad03snake

iTrader: (16)

I just put a jegs sfi flywheel on my 6.0 I turned the motor over by hand and found the flywheel hits the starter in one spot. I tried a few different ideas then bolted the stock flywheel and no issues. Jegs is sending another flywheel out asap.

turbodarryl

iTrader: (4)

Same exact problem, I sent my flexplate back and bought a SFI B&M flexplate, I have not had a chance to get it back together yet.

liquidmx

Bringing this back from the dead as I stumbled across it.
I too am (recently) having a potential out of round/too large flex plate issue and wanted to see if anyone else has as well?

The starter is hitting the flex plate due to it's circumference (not depth). When I shim the starter down the starter gears engage.

Flex plate is a SFI plate. I wont mention the name until I confirm for sure that is the issue.