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Discussion Starter #1
Ok, I recently had the problem of a starter that absolutely would not be consistent and keps working, kicking out, working, ect. I finally got that fixed with the right shims, and torqued it all down to 29ft/lbs. So all's fine and dandy until I decide to rebuild the starter drive since the drive gear was quite worn. As I was removing the outter starter bolt a chunk of the block popped off! Litterally a chunk of cast block popped off and landed next to me. It was about 1/2" wide and 3/4" long, and on the inside were the threads for the outter bolt. So I started freaking and running different ideas through my head. I couldn't retap the hold since there was actual metal missing. But these next two ideas kinda sound plausible.

A) Drill the hole through the top of the block flange that the bolt threads into (like 3"), and use a long bolt with the head at the top of the block and have the nut go on below the starter. I'm leaning towards this idea.

B) Weld in a 3/8" stud with lower threads for a nut below the starter. I don't like this idea too much, since I can, but hate welding cast.

So what do you all think? There arn't enough threads left for any bolt to tighten up, so I need something that I can tighten down real good. If anyone has any other ideas, feel free to let me know. I'm desperate here.
 

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Build it right the first time
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i would weld in a stud myself, i know welding cast is pretty crappy but it can and has been done with sucess :p
 

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Lost in the 60's
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Drill the hole about an inch deeper....thread then use a longer bolt for that hole.
 

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Discussion Starter #4
Thanks for the quick responses. Kuhn-77, I guess I'll dig up an old piece of cast and see if I can get the feel for it again. Hopefully that'll work out.

Henry Highrise, normally I would do just that, but that part that chipped off was so far up that there's only about 1/2" of solid metal left above and below it.
 

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I wonder if you can spray weld the piece back on? Would be easy if it was a bare block.
 

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Discussion Starter #6
Alright, I gave the welding a try. Looked real good too. :thumbup: Anyhow, got it all bolted up and went to tighten down the nut on that new stud and the rest of the flange just shattered and fell away in pieces. :pain: I'm begining to think this block is just a POS. I've heard this is quite common on modified stocks where they run very high compressions, and I was told that they make a bracket that bolts to the frame rail and bolts through the outter starter bold hole, acting as the outter bolt. Anyone every heard of this? I'm desperate! :pain:
 

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It'll go, or it'll blow...
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I've had a large chunk of a 400 SBC block break off at the outer bolt hole years ago.

What I did (with engine in the car, using a right angle air drill when needed) was basically replace the threaded part of the block that cracked off with a chunk of steel located about an inch or two higher up on the outside block. Drilled the engine block in the bellhousing area (two 5/16 holes.) Tapped these holes to 3/8-16 UNC. A chunk of steel about 1"x1"x2.5" high is bolted to these holes. Using an old starter nose and what was left of the outer hole in the block as a drill guide, drilled into the chunk of steel. Removed chunk of steel, drilled the hole deeper and tapped to 3/6-16 UNC. Had to cut extra long thread with a die in a long 3/8 bolt to use as an outer starter bolt.

Basically, the starter has a outer bolt about 4" longer than stock to screw into threads that are tapped in a chunk of steel, that is bolted onto the bellhousing area about 2" on top of the starter pad.

I don't expect it to last forever, but it saved a good running engine. If the car didn't have a monster oil pan and tight clearances from the Ultrabell making engine removal a pain, I would have done the same type of repair, but on an engine stand. Anyway, been using it on a 11.5:1 400 SBC for a couple years now...
 

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Discussion Starter #8
Cool thanks. I noticed your post about this in an older topic and was just about to PM you. I'll give it a try.
 

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This is an uncommon problem but lots have heard the story. Many methods of repair have been used and some survive and some don't. Essentially the block is junk when you are done with it, so be prepared to build another one at all times.
 

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Discussion Starter #12
Alright, thanks nova.

I'm definitely not looking for a long term fix, just temp. This engine's out of here as soon as I get my 327 done. Now I wish I had a manual trans. :spank:
 

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pasadenahotrod said:
This is an uncommon problem but lots have heard the story. Many methods of repair have been used and some survive and some don't. Essentially the block is junk when you are done with it, so be prepared to build another one at all times.

uncommon maybe, but I never owned a Chevy till 04 (except a 2dr corvair V6 w/2 1 barrel carbs and a 4 speed)but my buddies were/are all chevy fans. I've seen this broken block at the starter 2 Xs in the 80s, both were chevy P/Us one was a ole high mile beat & rusted 69 work truck one was a 72 swb stepside (basically a show truck) both were stock 350s 4 bolt main blocks. one was fixed with a jerry rigged turn buckle setup and the other was (some how) jerry rigged too. the 72 got a rebuilt 350 w/new block and the 69 was parted out.

Mustangsaly
 

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I have fixed several over the last 3 or 4 years. I get the tig welder and braze the broken piece back on with silicon bronze rod. If the piece is missing then I just braze a piece of mild steel on. I then redrill and tap and use as long a bolt as can be fit in.
I guess a stud could be brazed in also, I'd try to braze it in at the top also.

An oxy acetelyne torch can be used to do it as well as a TIG.

Make sure you use the front support for the starter. If you don't have one , get one.

I think that brazing is better in this type of situation as no major metallurgical change takes place in the cast iron. The silicon bronze rod is pretty strong. Welding would require preheating and a slow cool and if the wrong rod or method is used, can make the welded part brittle and useless. .

Here is a welding advice website that I found the other day. it is full of info about welding cast iron. There are several links in the text, follow those as well. The info seems endless.
http://www.welding-advisers.com/Welding-cast-iron.html



Hope this helps,
Mikey
 

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Discussion Starter #15
I would have just brazed a whole new piece of steel to it or have taken the block to a shop, but thanks to novajohnb's description of his bracket, I think I've come up with a nice simple fix that'll just bolt up using the bottom transmission bolt on that side.
 

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It'll go, or it'll blow...
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Here are the pictures. This is on a high compression 400 and lasted for years, so it should be fine for a lower compression engine. I have no reason to believe it would not last for many more years. I certainly wouldn't want to junk an engine that had lots of $$ in machine work just because the starter thread is gone.

It's been so long since the repair that I thought I had though I had two bolts in the bell housing, when there is only one. This was done with the engine in the car using a right angle air drill and short bits. If I had the engine on a stand, I'd fabricate something more substantial.

The problems I see with welding are
1- cast iron can takes loads in compression, but not tension or bending. Think about the forces that would act on the repair.
2- to weld cast iron you really need to pre and post heat the part. To get the block hot enough in this area, I'd worry about heat affecting the rear main seal and oil pan gasket if the repair was attempted with the engine inplace.
 

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Discussion Starter #17
Thanks. Turns out theone I made looks pretty much just like that. I'll let ya know how it works, and post some pics.
 

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Discussion Starter #18
:mad: Gah! I swear this engine is the biggest P.I.T.A ever! I installed my new bracket and everything, all seemed good. The starter couldn't be moved at all. Starter it up and it sounded good. Did this about two more times and worked great, so I took it for a drive. Got about a mile and the engine shut off, long story don't ask. Anyhow, I go to start it and it just grinds. That's all it will do now, but the starter's rock solid. I can't use an outter shim because of the bracket I made. Any ideas? I'm thinking of having the inner side of the top of the starter milled to bring it in closer to the flywheel. :pain:
 

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Discussion Starter #19
Ya, that's what I thought was the initial problem, so I replaced the bendix before going through this bracket process. I looked at the spot on the flywheel where the bendix was making contact. The teeth are worn, but I've seen alot worse. Only about 1/16" is rounded off, so there should be plenty for a properly aligned starter to grab. I think I just need to figure out how to get the bendix a lot closer to the flywheel, I can always shim it back down on the inside, I just can't use half a shim on the outside to bring it in.
 

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Discussion Starter #20
No one has any ideas? Has anyone ever had a starter ground down to fit better? There's got to be a solution to this, if only for a short time.
 
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