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So I finally got a starter for the 356 engine I got a few months ago. Thanks to the Flackmaster for sending that behemoth of a starter my way.

So I got it installed, and it cranked pretty well for almost one revolution, when it suddenly seemed tight, and before I had the chance to cut the power, there was a sickening crunch and the distributor stopped spinning (though the crank now spins beautifully!)

I don't have a socket that fits the crank bolt, but I was able to get the timing cover off just far enough, to see that it appears the cam sprocket has shattered. Has anyone ever seen this before? What could have caused it, stuck valve perhaps? Should I throw a timing set at it, or should I focus on the 359 I have as well, that I know turns over smoothly and the cam is actually doing something?
Unfortunately, that motor needs a lot more parts to be useful than the 356, and I'd need to go starter shopping again.

I don't know whether the problem I experienced is the same but I had a similar outcome with a 282 motor. The oil pump gears had fractured and jammed, causing the camshaft sprocket to strip its teeth while trying to continue turning the oil pump. Replacement gears for the oil pump and another camshaft were necessary to get the car back on the road. Good luck with it, John

I think that I have a 327 starter. I'll have to look. It should fit a 359. Go with the 359. Word on the street is, you'll be glad you did.


Whatcha gonna do with the broken 356?

I was hoping to drop the 356 into the car with transmission to get it on the road as soon as possible, then I'd have the chance to strip the 359,go through it, and get it right before putting it in the car.

Can the oil pump be removed externally? That sounds like the most likely thing to be bound hard enough to break a gear.

Yes, the oil pump can be removed externally.
My GUESS is the camshaft sprocket fractured as a result of stuck valves. Its a heck of a sprocket too, cast iron..
I don't think any of us would be surprised with stuck valves, common.

And if valves were stuck badly enough to break a gear the associated lifters and maybe tappets are likely now total garbage too. NOS hydraulic lifters for the 356 are all but extinct, expensive if you can find a few, and even good used are getting harder to come by.

Even if stuck valves are not the problem, I would recommend making sure they are all freed before trying to start the engine again. On the V-8 engines a stuck valve is known to bend its pushrod.

Also like Howard suggested, be sure to check that the tappets move freely too.

I did take the side covers off to see if there was anything obvious, and the mechanical bits looked good, even seemed to have a bit of fresh oil on them that surprised me. There was a fair amount of baked in sludge though, all around. The front tappets were all free and rotated very smoothly, the rear ones seemed like they were on lobes so without being able to rotate the cam anymore, I wasn't able to properly check them.

I don't have my flathead spring compressor here to check the valve operation either, if there's a trick to do it without, let me know. I wonder if I can fit my c clamp style around it... 🤔

What would ruin the lifter if that is what bound it up, just it and the cam digging into each other, or something internal?

Quote:

What others have reported is the lifters become stuck in the tappet. With a non moving valve the compression of the cam raising a lifter that cannot move or collapse anymore causes the remaining trapped oil inside the relatively thin lifter bodies to balloon the body out and more or less affix the lifter to the tappet. Even if the lifter is able to be removed from the tappet the swollen body and that lifter will no longer function.

Ok, so fingers crossed that didn't happen lol. I definitely have stuck valves, the c style spring compressor did in fact fit, and all but two lifters are free in the bores, the other two the valves are stuck on hard and won't rotate, probably are the problem children.