Rip 302, 1985-2016

[cb84capri]

Here's what happened when my .020" over 302 decided that it had enough of my s__t after 11 years. Wound it out to 6k in 2nd getting on the expressway, big bang, engine shut off instantly. I saw a light smoke cloud behind the car and smelled coolant, so I knew it was bad and didn't try to restart it. I was going fast enough I was able to coast and get it off at the next exit. I think #5 cylinder wall blew apart and locked the piston in it's bore as I see no damage to my head, and I think the rest of the damage was due to this. Or did the rod pin break free of the piston and punch the cylinder wall first? I guess I'm not entirely sure. I still have to take out the valves and inspect them. Sorry some pics are upside down as it is on my engine stand. What do you guys think happened?

#5:




Pan off:








#1 piston




#5 still in block


#1 broken cylinder wall


V6 LOL:


The pile... front main, arp oil pump driveshaft, hypereutectic speed pro piston skirts, snapped timing chain, chunk of block



Don't have any of the timing cover, but it was turned into scrap too. Had a spare roller block laying around, I guess I'll make a 347 stroker out of it.

Cale

[Fearnot]

Now that's awesome!

[federal officer]

no offence but VERY well done sir !!!!

[PaceFever79]

Looks to me like the wrist pin broke then beat the motor to death. I had that happen to a 429 of mine. Almost the same scene too, I was pulling out from a red light and wound out first gear and bang.

Anyway, sorry, but that is impressive!!

[conmech]

Kaboom......ow.

Pics of new during build, please.

[PaceFever79]

PS

I never really trusted those hypereutectic pistons. The original forged TRW slugs are heavier but damn near indestructible. Not saying for sure that is what failed but it would not surprise me a bit.

[mmb617]

A few years back I had a 393 let go right at the stripe. Pretty exciting as I went through the traps at 110 sideways.

In my case it was determined that the cylinder wall let go first, locking the piston in the bore and breaking two rods, which then decided to make their exit via the oil pan. I did not however manage to snap the crank in half, so you beat me on that count!

Anybody interested in some slightly used rods?








When mine broke it sheared the cam pin off which is probably why all my exhaust valve were bent. The intake valves were ok though. No other damage to the heads.


This isn't exactly what they mean when they talk about "canted valves" is it?





At least now you have a good war story to tell, if that's any consolation. Oh, and an excuse to build your 347.

[PaceFever79]

Hahaha, yep!

First blown is a milestone

[floodstang]

I don't think that will buff out.

[JTurbo]

Ouch! How about some JB Weld.....

[JACook]

I'm going to suggest someone, at some time in this engine's life, used the starter to loosen/tighten
the crank damper bolt. Learned that lesson the hard way, after losing a 390 and a 302 the same way.
The remains of the crankshaft looked exactly like yours, as did the front block bulkhead.

I have this bit of desk art to remind me to not ever do that again...

[xctasy]

The John Lee Hooker Boom , boomb, boomb, booomb...

"Is It Serious? "

https://www.youtube.com/watch?v=BsO9WEwitfo

Excuse the French....

[Ethyl Cat]

That crank broke at the rod filet and the rest of the damage followed IMOP.

[cb84capri]

Now that's awesome!

no offence but VERY well done sir !!!!

Hey if you're going to blow it up, might as well do it right haha. Thanks!

Looks to me like the wrist pin broke then beat the motor to death. I had that happen to a 429 of mine. Almost the same scene too, I was pulling out from a red light and wound out first gear and bang.

Anyway, sorry, but that is impressive!!

Hey thanks! Did you do any damage to your heads when that happened?

PS

I never really trusted those hypereutectic pistons. The original forged TRW slugs are heavier but damn near indestructible. Not saying for sure that is what failed but it would not surprise me a bit.

I have heard nothing but bad about hypers, These did last me 11 years though. I don't plan to use them in anything I put together from here on out.

A few years back I had a 393 let go right at the stripe. Pretty exciting as I went through the traps at 110 sideways.

In my case it was determined that the cylinder wall let go first, locking the piston in the bore and breaking two rods, which then decided to make their exit via the oil pan. I did not however manage to snap the crank in half, so you beat me on that count!

At least now you have a good war story to tell, if that's any consolation. Oh, and an excuse to build your 347.

Yeah I remember seeing that on here way back when. I didn't know it happened at the top end of the track!

I'm going to suggest someone, at some time in this engine's life, used the starter to loosen/tighten
the crank damper bolt. Learned that lesson the hard way, after losing a 390 and a 302 the same way.
The remains of the crankshaft looked exactly like yours, as did the front block bulkhead.

I have this bit of desk art to remind me to not ever do that again...

I am kind of doubting that in this instance. This engine was out of an early model year 85 CFI Mustang. It wasn't very high mileage when we tore it down to rebuild, it was bone stock down to the cast iron manifolds, and the balancer was definitely the original. I remember because I replaced with a better condition used stock one it as it was pretty dry rotted around the rubber ring. The stock replacement was impacted on. I did torque the balancer bolt against the transmission in gear when I put on the profeessional products sfi one on, but this balancer has been on the car for the last 9 years and I drive this car pretty hard. When I would set my valve lash (mechanical flat tappet) I would turn the engine by that bolt. I remember you talking of your failure over the years and I made sure to never try the starter trick. Maybe the balancer itself triggered this? It might not have been the best balancer being Chinese and all, and I think 50oz imbalance is garbage anyways. What is the point in 50oz, to save money on crank counterweight metal? Ford going 28oz to 50oz to me is like going from bad to worse. I'm planning on putting an internally balanced crank into my 347.

The only thing I noticed before this happened was that the car was crackling and popping just a little bit slowing down for traffic lights in gear, and it never did this before. Other than that everything was normal.

The John Lee Hooker Boom , boomb, boomb, booomb...
"Is It Serious? "

https://www.youtube.com/watch?v=BsO9WEwitfo

Excuse the French....

That made me laugh! That was pretty much what I said when I heard it go, haha!

Cale

[grabbergreen84]

I'm going to suggest someone, at some time in this engine's life, used the starter to loosen/tighten
the crank damper bolt. Learned that lesson the hard way, after losing a 390 and a 302 the same way.
The remains of the crankshaft looked exactly like yours, as did the front block bulkhead.

I have this bit of desk art to remind me to not ever do that again...

I read this earlier this afternoon, and wondered how this scenario could possibly be!

But now maybe my mind is wrapping around it...
Is the "propelling from one end and abruptly stopping with the other" causing an undue torsional dynamic/twist/stress upon (through the entire length of) the crankshaft, precipitating failure?
I guess the rod filets being farthest from the center of axis bear the brunt of said torsional dynamics?

As the engine runs, the twisting force would be equal throughout the length/portion of the crank where the rods ride, and met with resistance only at the flywheel end.

And turning the crank from one end while resisting from the other creates the undue twist throughout the entire length of the crank, flexing and fracturing it at its outermost diameter?

jus' theorizin'...

[mmb617]

Are those the twisted rods used with twisted wedge heads in order to have all your parts match?

[wraithracing]

Very well done I must say!

As they say if your are gonna go out . . . Go out with a BANG!

[JACook]

...The stock replacement was impacted on. I did torque the balancer bolt against the transmission in gear when I put on the profeessional products sfi one on, but this balancer has been on the car for the last 9 years and I drive this car pretty hard.

Torquing a damper bolt against the transmission is not likely to cause a problem, because you're applying a steady
force. I'm ambivalent about using an impact gun, because while it's definitely frowned upon with some engines, I
don't know that it's a problem with the 5.0. But having had a crank break in the same place yours did, it's just not
something I ever do.

When I tore down my engine after the crank broke, I could see very conclusive evidence that the crank had been
running with a crack in that area, until it didn't anymore.

[PaceFever79]

Man looking closer at the photos, that is one mutilated motor. It's hard for me to say with any conclusion what caused the thing to come apart. Usually that sort of total destruction is from detonation like from nitrous or too much boost or just a ridiculous amount of RPM from a "money shift". All I can say for sure is you won the grand prize!

[dynodon64]

Crank failed and the rest followed.

[PaceFever79]

Crank failed and the rest followed.

Yep. The wise money bet. But holes in the cylinder walls cause me some doubt. A sudden jam or jack could cause the crank to fail. When I look at everything all together it's not 100% (in my mind)

[cb84capri]

I know it has been awhile, but I had to look up this thread and never realized that I hadn't gotten back to it.

Anyways, I determined that one of the front pistons broke and let the rod and wrist pin go free. It happened when I pushed in the clutch to shift from 2-3. My guess is that it happened on the intake stroke when the engine was unloaded and rpm climbed. The tension force ripped the pin out of the hypereutectic piston. This made the hole in the cylinder, and when the rod came up back into the broken piston the rings locked in the hole and the force that had nowhere to go blew the front main out and snapped the crank. I know the hole was punched as the rod was going down though, as my cylinders heads and valves somehow miraculously made it out of this mess unscathed. I suspect that the balance wasn't quite right on this engine, my balanced 347 is a lot smoother.

I held onto that broken engine for awhile, and turned it in as a core at a u-pull yard on another engine.

Cale

[erratic50]

Look up piston weights - most forged pistons these days are LIGHTER than the H’s

Bummer she let go.

pretty common with 347’s though

[xctasy]

I'm going to suggest someone, at some time in this engine's life, used the starter to loosen/tighten
the crank damper bolt. Learned that lesson the hard way, after losing a 390 and a 302 the same way.
The remains of the crankshaft looked exactly like yours, as did the front block bulkhead.

I have this bit of desk art to remind me to not ever do that again...

I'm kind of thinking its just a cast crank and thin wall Ford thing.

Every recent rebuild of Cleveland foundry engine after late 1968 has the suggested Ak Miller 243 to 187 thou metal reduction on heads. It was similar on blocks as well. We say big block and think FE FTP Le Mans winning thick-wall castings, but Henry Ford II had to pay the rent, and IMHO, it came out of grey iron in all Ford blocks except 385 Lima's and FT's, and the 1978 to 1982 351M/400's with the revised 335 heavier casting.


I've had what I think are nine destroyed Cleveland foundry engines since 1987 when I assisted my mate Blair in his 1982 XE Geelong Cleveland 351 C engine rebuild.

1. Blair Gregory's 351C (Geelong Foundary, Australia; made on Cleveland Foundry 2 equipment)
2. Paul Richardson's 302 Windsor Cleveland foundry (freeze cracks, great engine, over heated only on 2 to 6 minutes operation)
3. Ty's 289 32 Four door, another Cleveland foundry engine
4. Jimmy Clydedale's 65 Ford Fairlane with 2V 302 Cleveland foundry engine (1993. MCraes mine )
5. One 302C 2V 1971, (Geelong Foundry, Australia), XY engine.
6. One re-sleeved OEM 1972 RPO 083 FordFalcon GT (four bolt main M code 351C 4V, ex US Cleveland Foundry 2 )
7. BRWSaver's 3.3 liter 1978 Ford Fairmont SportCoupe engine at 24 Hrs at LeMonz
8. Does10s 250 block, turbo 62 Falcon engine, bore split. He said frozen wrist pin.
9. My mate Mike1157s 250 Gila Monster engine, over-bored and re-sleeved. Cracked in the middle.

That's enough to suggest its not the worlds best grey iron casting. That's not to bad mouth the process, the plant, or the machine processes that made it and there ilk. Those are the only facts I have had in living memory. Mass production actually improves quality because failures in service can be tracked and traced from date codes, and Ford worldwide did that.


Bore splitting is endemic in 302's.

Despite what is said about the FE 390 on the internet, the 390 is not a thick wall engines with 200+ thou of metal everywhere.

Q: "were there ever thin-wall 390 FE engines"
A: "Despite what you may see on the Internet, it is best to assume you cannot overbore a (4.050") 390 block to (4.130") 428 dimensions. These are thin wall castings, and odds are you will eventually split a cylinder even if you get it running"

Ford FE Engines
Barry Rabotnick



Paperback: 144 pages
Publisher: CarTech ( June 5, 2018 )
Language: English
ISBN-10: 1613252447
ISBN-13: 978-1613252444
Product Dimensions: 8.5 x 0.4 x 11 inches
Shipping Weight: 1.1 pounds (View shipping rates and policies)

"https://books.google.co.nz/books?id=q_VeDwAAQBAJ&pg=PA13&lpg=PA13&dq=were+the re+ever+thinwall+390+FE+engines&source=bl&ots=8Sl8 Kv93nO&sig=ACfU3U1pQnd28NzntqTdHfAE2PartArTzg&hl=e n&sa=X&ved=2ahUKEwjs2ua19enpAhVSzzgGHauHAh8Q6AEwFn oECAsQAQ#v=onepage&q=were%20there%20ever%20thinwal l%20390%20FE%20engines&f=false"


The FT 360/390 truck engine generally is thick-wall.

Lots of people overbore 352/360/361/390/391's into fire breathing 410/427/428's, that doesn't mean its a thick-wall block.

https://www.fordfe.com/minimum-cylin...ss-t60493.html

I was wondering what you all think is a safe minimum cylinder thickness for a 9.5:1 FE street motor. I have a block that is a good standard 428, but it sonic tested as thin as .075 in one place. Most of the cylinders are in the .090 to .115 range.

[cb84capri]

Look up piston weights - most forged pistons these days are LIGHTER than the H’s

Bummer she let go.

pretty common with 347’s though

I was comparing the 302 I broke to the 347 in the previous post. My 347 is still going strong.

Cale