396 Broken Block

[Bill B.]

I was helping a friend get his 65 big block started yesterday. The starter would not engage and we found the part of the block broken off. Specifically, the outboard portion of the block where bolt goes up into the block is broken off. The piece that broke off was laying on the floor. After a phone call to a local shop we were told that this has happened before with 396 blocks and broken piece can be welded back on once the engine is pulled. My question is, has anyone heard of this problem before and is there another fix besides pulling the motor. Thanks in advance for any help.

[William C.]

Re: 396 Broken Block

Yes, not uncommon, no-cannot fix without having the bare block out of the car to the best of my knowledge..

[Steven S.]

Re: 396 Broken Block

Your best bet to get a good quality repair is to take it apart. Cast iron needs special attention to weld properly.

[Clem Z.]

Re: 396 Broken Block

I was helping a friend get his 65 big block started yesterday. The starter would not engage and we found the part of the block broken off. Specifically, the outboard portion of the block where bolt goes up into the block is broken off. The piece that broke off was laying on the floor. After a phone call to a local shop we were told that this has happened before with 396 blocks and broken piece can be welded back on once the engine is pulled. My question is, has anyone heard of this problem before and is there another fix besides pulling the motor. Thanks in advance for any help.

most likely caused by engine "kick back" while starting the car. check the timing after you get the repair

[Ray G.]

Re: 396 Broken Block

Hello;
After the block repair(which experience shows will require removal) check for the correct starter bolts, that achieve proper torque before bottoming, and also a starter bracket.
Hope that helps.
Ray

[William P.]

Re: 396 Broken Block

Hello,

I remember seeing on "The Last Sting Ray" that the Nabors brothers had to have that same piece welded on the original block due to it being damaged in shipping to them. It did not seem to harm that car. I also believe that the correct tapered / knurled starter bolts correctly torqued with the correct side support bracket, and correct initial (Base) ignition timing are a great place to start in stopping this from happening again. Not knowing what distributor you are currently running, it would also a good idea to make sure the advance weights are not stuck in the advance position. Hope this helps!

Bill

[Michael B.]

Re: 396 Broken Block

I know that is one sick feeling on a matching numbers block.

I dealt with this on my 69 L68. Only I didn't locate the broken piece. I was able to repair it with the engine in the car. I used a steel coupling nut that I cut in half lengthwise and filed to match block. I placed a bolt in the exposed threads on the block and then placed the half coupling nut over the bolt to line up the threads.

I placed an insulating welding blanket between the block/bellhousing and the firewall.

I was concerned about cracking the cast iron from uneven heating. Since I couldn't start the engine to warm the block, I used a heat lamp overnight. Even with that, I preheated the area with the torch and brazed the coupling nut onto the block from the top down on both sides. The the starter bolts pulled up snug and I haven't had any problems with it since and that was about 5 years ago.