Amc 304 Worth Saving?

Dunno - my '73 CJ-5 threw the rear driveshaft at about 20K original miles. Your mileage may vary. I would not look to the 304 CJ-5 as an example of good practice.

 

I dunno either, you could very well be right, It might just be one of those things you just have to try it and see what happens.

 

I’ve started tearing down the engine. This is what #7 cylinder shows:





The exhaust manifolds are off - had to cut off the bolt heads due to rust. The bolts should come out OK.

Tomorrow, I should be able to get the heads off to see what sort of destruction lies inside. Then the oil pan.

Jon B.

 

Just minor carnage so far! Back in the late ‘70s, I bought a Commando with a pair of rods sticking through the forward side of the block and pan rail area (Dauntless V6). The guy drove it off the beach like that to the local service station to find the problem. I ended up buying it for parts for $35. I added some oil, started it up, and drove it about 7 miles home. The pistons were pushed up near the top of the cylinders 1 and 2, and the rods were broken off with both big ends still more or less intact on the crank journal. I drove it around the neighborhood on 4 cylinders for the better part of a week before breaking it down for parts I got almost $250 selling parts off it.
I’m curious what turned loose in yours. -Donny

 

Happy late Birthday and welcome to the club! I suppose Dandy dropped the ball on this one.

 

Your engine is missing the rocker arm bridges.

 

On an AMC 304? Son 2’s didn’t have them, either.

Jon B.

 

Discussed in a previous thread - http://www.earlycj5.com/xf_cj5/index.php?threads/159616/page-2#post-1855481

Bridges replaced ball pivot rockers for 1973.

 

The elusive V-7!

 

It might be a V6! Number 8 piston looks as though it has/had about a 6” stroke; it’s way, way down in the cylinder. I have the bolts out of the mounts, so will likely lift the engine out tomorrow. The beetles & box elder bugs are thick, so I don’t want to open the big shop door to get the tractor in to lift.

Jon B.

 

Picture of #7 piston top:



What doesn’t show is that it’s not “square” in the bore. I suspect that the top of the piston broke off. I’ll know soon enough.

Jon B.

 

Intersting. I pulled a 304 out of a 73 Commando and it had aluminum bridges.

 

Now that I’ve had time to think on it, the 304 in Son 2’s CJ7 DID have the rocker shafts running full length on each head.

Mine is a ‘72, so I guess it’s “period correct”.

I wondered if someone had just slapped on the data plate from a ‘72 but the SN is partially legible in the frame rail, and what I can make out matches the VIN.

Jon B.

 

More”Rapid Unscheduled Disassembly” pics here. This engine turned out to be the very rare, highly-sought-after V5!!



Both the block and the crankshaft are trashed:



Off to the scrappers it goes.


Jon B.

 

Oh yeah…

This collection was in the oil pan sump:


Three rod ends & caps, one wrist pin, piston skirts and block fragments. Ugh.

Jon B.

 

Cool. Intentional destruction?

Power through!

 

It does make me wonder. Throttle stuck wide open and driver panicked, maybe? It wasn’t overheated or run w/o oil.

Maybe a PO’d buyer returned it to the seller to teach a lesson…? I’ll never know - or care, even.

Jon B.

 

Awesome carnage. Can't say they didn't get everything out of it.