Crazy (imo) starter bolt theory. Keith we need your input

[bluex]

This was a question/scenario I saw posted today on the book of faces:

For some reason my starter sits too far from my flexplate. Tried different starters. All same problem. Then I found this

Any GM technicians in here that can confirm?

You have a block with The Problem, wherein the starter bolt holes are too far from the crank. About 25% or 33% of 70s Chevy blocks have it; BB, SB, and 6-cyl. 1 gang-drill machine at the foundry was effed from about 71 to about 79, out if the 3 or 4 that they had (hence, 25% or 33%; not 30%, 36%, etc.) You have no idea how many cars and trucks have been scrapped for that. The whole non-existent "heat soak" myth got started that way. Bet you got it as a running short block for too cheap from somebody that seemed too eager to get rid of it for some excuse that didn't make much sense?

The block is permanently fornicated, and has been from the day it was born. There's not really any way to repair it.

The regular starter is part # 3510.

Find part # 4347 instead. It moves the starter shaft inboard about .100" from where the 3510 puts it. It will require different bolts but those are available in the Help! aisle. It was the factory's "solution" to the millions of defective blocks out there, but was only made readily available to fleet customers (taxi co.s, police depts, etc.)

I work in the auto industry now (since 2005 actually) an I dont see this as a viable explanation to this problem. I know things weren't as strict in the 70s as now but this just goes against all the reasons why automakers use assembly lines....

[Keith Seymore]

No - that sounds pretty far fetched. Those are some oddly specific speculative statistics.

Additionally - small blocks and big blocks weren't made in the same place so even if a process was messed up it wouldn't affect both of those families of engines.

K

[bluex]

Thanks Keith!

[bluex]

That also makes sense not having different engine families on the same line. I should have picked up on that as well. When I was in the machining part we did one engine series in our building, from machining to final assembly an testing. Then it went over to assembly. When they wanted to start making a 4 cyl there they built an entire new building for that....

[kikkegek]

he thanks gfor opening this topic.

It was me, that started it on FB.

my small bock is driving me crazy. Tried stock starters, mini starters, high torque starters, replaced flexplate. noything works. The starter is just too far from the flexplate.

video of the distance:
https://youtu.be/VX_fxiU3800

[TrailerTrash]

I have this exact same issue. tried four different starters. once I determined it wasnt the starter i started shimming. i had to put two starter shims on the outer starter bolt to tilt the starter in towards the flexplate.

I have talked to alot of people about this. Some people have never used starter shims. some people have always used them. I had to use them on this engine but not the first engine in my truck nor on the engine in the 79 i used to have(that was a crate engine from who knows how long ago)

[mongocanfly]

ill have to say I've never seen or heard of this til now...

[jjzepplin]

Me either.

[Killer Bee]

wow, what a tall tale there..

if the removal of all shims was insufficient for the correct spacing, all nicks and dents on both mating surfaces were knocked down, the flexplate ring gear OD and tooth wear is verified in spec, and still not close enough, a small fly cut on the starter mounting surface would be my solution if I was unable to align it any other way..

good luck!

[jjzepplin]

So at some point this engine was starting fine right? Where is the starter that was working? Never turn in your "core" until everything is back to normal.

[kikkegek]

Originally Posted by jjzepplin

So at some point this engine was starting fine right? Where is the starter that was working? Never turn in your "core" until everything is back to normal.

nope, I bought it second hand, without a starter. Came from America to Europe as a spare. rebuild it. And till the day, allmost three years now, never found a starter or flexplate combo that had normal spacing. they are all to far off...close enough to start the engine, but loud as hell and will start grinding within weeks/months

[bdiamond]

Could it have been line bored excessively? I agree with Killer Bees response.

[Bluestep]

To start with, the engine in the video was using studs and nuts to hold the starter on. This is not correct! To register correctly you need to use the knurled bolts that Chevrolet used. Most parts houses can supply them. Use the correct starter for that year of block and use the bolts that match that starter. At some point GM went to metric bolts so the bolts and starter need to match. In other words metric bolts with metric starter, imperial bolts with imperial starter. The bolt shoulder should fit snugly in the block's countersunk holes and it should fit the holes in the starter snugly. If the bolts are loose in the holes in the starter, the starter can move around and will not fit the same each time it is loosened and retightened.
Get a new starter or a new nose piece, as the rebuilt ones have been remachined to clean up the surface and they will require shimming.
Millions of these engines were built and operate without problems. I believe the problems start with rebuilt starters, aftermarket flywheels and people trying to reinvent the wheel.