To Heli Coil or not to Heli Coil

[smsdm02]

Well folks, here is the problem:

I recently pruchased my very first truck (ever!); 72 Chevy Longbed, 350, 350 Turbo Trans. Runs great, drove it home about 150 miles, no problems. Got it home, drove around for a few days, still no problems. About a week after purchasing it, I noticed a small starter grind on the beginning of each key turn. Finally, about 4 days ago, it wouldn't start and I got a motor spinning sound with just a bit of grinding, no engine turn over.

No problem, I just check the flywheel for bad teeth (no bad teeth present), replaced the starter and good to go. It starts right up with no problems and I get it home, turn it off and go to bed. Get up the next morning and same motor spinning sound with just a bit of grinding with no engine turn over.

I pull the starter off (to test it, it's fine) and see that the hole on the edge of the block where the outboard starter bolt bolts in has a crack on the outside. So here's my question:

Do I try to heli-core the block where the bolt goes, or do I replace the block? I have access to another block, tools, engine lift, etc. (My Fiancee's dad builds drag trucks for fun)

Is it worth it to try, or will I just make it worse by trying to heli-core it?

Please bless me with your knowledge and opinions, O Gurus of the 67-72. Thanks a bunch!

[pat 70/71]

I would try to save the block by any means possible. its a dd correct? maybe look into welding up the crack(how long?) Heli coil or drill & tap it out to a larger size bolt (not a guru) cheers, Pat

[Lee H]

If the blocks cracked and separating it can not be just heli coiled, it may be able to be welded and then treat the threads as required.

[Sinister]

Originally Posted by Lee H

If the blocks cracked and separating it can not be just heli coiled, it may be able to be welded and then treat the threads as required.

[stich626]

they have 2 starters
one with the bolts in a line. bolt --------bolt


and one with one bolt at a point farthar back


bolt

................................................bolt
your block might be drilled for both.. even if it is not you can drill the block for it..
(mine was drilled just not tapped)
good luck..
you will need a different flywheel, (think 153 tooth one)

[69 longhorn]

The outer bolt hole is the same for either starter tho. Another thought.....if the engine is fresh , & you dont want to tear it down, you can add the clutch peddle. The truck stick bell bolts the starter to the bell crazyAl

[low'n slow]

My son had a block like that. We made a bracket that tied the end of the starter to the block with one of the oil pan bolts. Worked for 2 years until he sold it.

[smsdm02]

This truck is intended to be a daily driver (even though it's not pretty), but I really want to keep it around as it's a great way for my father, soon to be father-in-law, and I to get together and spend some time.

I plan on using it to haul instruments (I'm a music teacher), help buddies move, or maybe just take the lady for a ride. Versatility and reliability is a must, so please keep the suggestions coming! Thanks everyone!

[rsavage]

+3 on taking it somewhere to get it welded. If it's not possible, then go to block change.

[dwcsr]

Originally Posted by low'n slow

My son had a block like that. We made a bracket that tied the end of the starter to the block with one of the oil pan bolts. Worked for 2 years until he sold it.

Tis would be my fix until the motor is replaced or the bolt hole fails completely.

The problem with a heilicoil is that the bolts are should bolts and the recessed hole in the block needs to fit tightly against the bolt serations. If you heilicoil it you will drill out that tight fit and have more problems.

[slikside]

Not saying the crack is not the problem, but be aware that not all starters are created equal either. Years ago I was having a similar problem. The two starters I purchased from Kragen would be ok for about a week then I would start having grinding and gnashing problems (although it was engaging the flywheel). Anyhow, got tired of the runaround with the rebuilds from Kragen. Went to the Chevy dealer and got an ACDelco starter...end of story. That was nearly 20 years ago.

[BOZO]

You won't have much luck welding on the block, but brazing will work being as it is a cast metal. Also instead of a helicoil, use a Keenesert. These are threaded inserts which use the next size bigger threads drilled and tapped into the block then the insert is screwed into the block and the locking tabs are driven into the threads to hold it in place. Helicoils require a specific tap to create the threads and are more prone to pulling out than Keeneserts.
Some starters have a 3 bolt aluminum housing. Sometimes these can be used to drill and tap an extra hole in the block. Also, as posted earlier it is a good idea to use the front bracket (a stock Chevrolet item) to brace the starter whether you have a problem or not.

[Hubscrub]

i agree i would just have it welded if possible, i have motor in my nova that the hole starter ear was broke off and had it welded and has been fine for years (reason it was broke we got the motor out of a totaled 71? camaro)

[raycow]

You might want to consider a starter mounting plate like this.
http://www.classicchevy.com/chevy-en...1955-1957.html
It is used with a bellhousing mount starter, and those almost never have the kind of engagement problems you get with the block mounted type.

Ray