Tore down the 360 from midnight auto today. Without looking at the motor, or doing a compression test, I had no idea what was wrong with this old gal, aside from that when I added water to the cooling system, the thing made oil (and this was sitting) Anyhoo, the first thing I try doing is pulling out the dizzy. No luck. It turns, but wont come out. I pull off the water pump and notice the cracked timing chain cover. I forgot the balancer puller at the house so I take my hammer and bust out the cover. sure enough the timing chain was broke. I pull off the valve covers, turn the cam with a wrench and only 2 valves move. I notice 1 pushrod was 1 1/2" away from the rocker arm. Needless to say, a quick tug on the cam gear resulted in pulling out about 8" of cam. I had to beat on the end of the cam gear to get the dizzy out of the block. I look at the crank and notice that the teeth on the crank are GONE! I pull the manifold, nothing special. Pull the heads, notice one piston at the top of the bore, turned about 30 degrees. Turn the crank over, sure enough the piston doesnt move. Look at the other side of the motor, and there is ANOTHER piston that wont move, except this one is at the bottom, with rust all the way around the cylinder. I drain about 10 quarts of water from the oil pan, and about 1 quart of oil. Pieces of lifters come out.

Interesting recipe for disaster. 7000 rpm burnout=2 thrown rods, 1 broken cam, 2 lifters broken in half, stripped teeth on dizzy, and crank. This damage is without popping the pan off, there is no telling what the bearings look like!

Tony

'74 F250. 460, "beater"
'73 F250, "midnight auto"
'77 F250, 460 transplantee, "Flamer"

 

It's amazing how when one part comes loose most everything else usually does also. So are you going with a 390 now? Probably won't be able to reuse the block. What were you doing at 7,000rpm?

 

How did you get to 7000RPM on a 360. Seems like you'd have to be using rocket fuel, 1000CFM carb, Edelbrock Victor FE intake, and a real nasty roller cam. Well, the again, maybe you shouldn't tell us. Some of us are foolish/curious enough to try it :-)

 

7000RPM burnout on a 360 is uhm, pretty good... but bad too in this case

 

Hehehe, I ONLY WISH I was the person who did that (so I can get the first blown up the motor REAL GOOG thing out of the way). I Have nooo clue how fast this motor was buzzin when it blew up (with a 2v carb and headers) but it blew up baad. One of the pistons was shorn off above the wrist pin ( I couldnt find the pin in the pan either), the 2 con rods looked like spagetti, and there was a dent in the rod bearing 1/4" deep, and the bearings were unrecognizable. I havent really torn into this motor, but the block looks good enough to use again with a simple hone job. Anybody in NorCal want it for free?



Tony

'74 F250. 460, "beater"
'73 F250, "midnight auto"
'77 F250, 460 transplantee, "Flamer"

 

Sounds about like the way the 390 in my 73 f350 went.
Going down the freeway at about 65 motor go bang, saw cracks on the block bleeding oil/water, got it home and pulled motor.
Autopsy showed what happened. the camshaft snapped in three places, between the first and second lobes, between the second and third lobes, and behind the fourth lobe. the chunk with the third and fourth lobes fell straight down and got caught between the number
one rod and the side of the block smashing the rod and busting into
the water jacket.
This was an engine that my Dad bought from a junkyard and installed
about 79. On the side of the block was a tag that said FOMOCO remanufactured engine with the bore and crank specs.
First time I've seen a broken cam total an engine