W Guy

Same thing happened to me Mike when I over revved a 396 back in '69. The largest piece of piston I could find was the size of a nickel. Pieces were even in the carb!

Verne

MikeM

I still have a souvenir. I saved all the small pieces in a glass peanut jar. That's been 52 years ago. Every once in awhile, I'll pull that jar out and look at it.

I never tore up another engine after that by over revving.

cardo0

U might want to look in the JeepCJ forum for more specific information. To bad its a California car. That restricts your hot rodding options. I love to see CJ swaps. I think a Hemi CJ would be so badazz.

W Guy

That's really funny. I did the same thing only I used a Delco D409 rotor box. I had to open the lid for the reminder. Never blew another engine after that either...

Westlotorn

My son, the king of swaps is pushing for a LS conversion but this car needs to work very soon for college transport duty so a 4 cyl is going back in. Great idea though.

Frankie the Fink

Only seen a couple of failures that catastrophic "back in the day". I've taken great pains to tell my wife and daughter that if they hear a funny noise shut the damn car down unless they are somewhere dangerous.

With cell phones and AAA now there isn't quite the incentive to 'limp' to some gas station and grenade your engine. Its backfired a few times as I've been called out to the garage for the 180,000 mile Durango's occasional cold start up lifter tick which goes away in 5 seconds.

I'm OK with that.

Not sure I'd try to sleeve that for a kid needing daily transportation to college but that's just me ... others here know far more about engine internals than I do.

Westlotorn

I found another block so we will determine what to use and what to rebuild now.
I also found out my Sister mother of said nephew heard the noise and told him to stop driving the Jeep till he had his uncle listen. He did not heed this advice and now has one junk engine to admire. I enjoy working with this kid so no issue with me although I did tell him I would insert my boot firmly up his tail if he ever did anything this dumb again, he works hard and his attitude has been great, and humble. We will get it running again soon.
I don't think it will happen again. Thanks for all the support and good stories to laugh at.

I am also guilty so I should be more forgiving, at 18 I pulled out to pass a car that started accelerating as I was passing. Rather than shift and lose the race I let it wind a little more, to exactly 7,300 RPM and sucked a valve. This was at about 2 am so I drove it home with a heck of a clatter in the engine. The valve head had stuck in the forged piston and beat the hell out of the head and valve seat leaving it junk. New set of pistons, rings,bearings and a new head and it was back on the road.
It needed a freshen up anyway, it had been starting to smoke.
I have been far less willing to exceed the Red Line since that day.

MikeM

.............embarrassing, ain't it? Lose the race and blow too!

Westlotorn

Yep. but I have had 40 years to ease the pain.

tuxnharley

Wow - I guess I have been really lucky. The worst price I ever paid for my youthful stupidity when street racing and over revving was a few cases of pumped up lifters and bent push rods. Easy fixes!

Westlotorn

An Update for the Jeep project.
We got the Machine Work back from the shop Christmas Eve. Replacement block bored .020 over, decked and had the head rebuilt and crank polished. Had relatives visiting for Christmas so not much work done till after.
Assembled the block and started trying to remember where all the bolts and nuts went. We did take pictures and marked bolts to specific parts bags all marked but even with that we made mistakes. Mostly installing bolts where studs were needed.
We got it done and turned the key tonight, it fired right away. Held the RPM to idle for 10 seconds waiting for oil pressure, within 30 seconds the lifters had pumped up and quieted and oil pressure was at 65 lbs. By 45 seconds in we had the RPM at 2,000 and set a timer for 25 minutes to break in the cam. Used Sealed Power LL5 break in lube internally on everything, bearings, rings, camshaft, valve guides, cylinders, oil pump.
After 5 minutes with all checks done we started varying RPM, 1,500 to 2,500 slowly up and slowly down, continued till the cam break in was done.
For a full 15 minutes of this time the engine was puking a huge smoke screen out the back. I had warned my nephew this would happen. The exhaust had consumed much of the antifreeze from the previous engine after the old block was broken.
My wife had to call the fire department and tell them not to respond if our neighbors called in a fire. I ran three fans to keep air on the radiator and clear out the garage of smoke. The temp reached 200 and never varied. My nephew Jake is very happy and did a great job helping, he turned a lot of the wrenches and is very proud of his work. ( Vette helper in training )
The new engine purrs and seems to have turned out perfect. ( Fingers still crossed watching for that one item I may have forgotten. )
Oil Pressure held at 50 PSI hot, I was relieved because we chose to polish rather than turn the crank I knew the Mains and Rods were on the loose side but all seems good and most important he is happy and feels the work was worth it.
The funny thing about Jake, he was most impressed with his Brass Freeze Plugs, they looked cool against his black engine? Maybe that was like us adding a four barrel carb back in the day.

6T7L71CPE

Great Job!

tuxnharley

Nothing better than helping your kids/relatives/friends complete a project and learn something in the process!

Westlotorn

Thanks Guys. If you look close you can see I switched the standard chain hook on the engine hoist to a swivel hook. It helped two ways. I gained about 5 inches height for total lift because the hook does not dangle under the hoist by several inches now.
The better gain is full swivel even when loaded. It really helps on install to have more ability to swivel without fighting the chain.
We had to install the engine C2 style. Pulled the front tire and came in from the side.
Going from the front we had it all the way in, clutch going over the tranny spline when I ran out of room and the hoist hit the front bumper. Thanks to the Vette forum I knew to try the side, it worked fine. I think the hook was $40. and rated for 1,500 lbs but it was worth it.

427Hotrod

Great job...he looks like a happy guy...and he can tell folks he did it! Once you realize you can..the world opens all sorts of opportunities!

Hey...I always leave my brass freeze plugs unpainted also. They never leak or corrode...so when the engine gets worked on, I just smear some grease on them when I paint it and then shine up with a little Scotch Brite when I'm done! The ones in my 427 are about 35 years old now...and my 555" has had them in place for 15 years or so.

JIM

63 340HP

Good ending to the lesson, what will probably be his most expensive lesson. The resulting engine should easily go 200,000 miles without a problem if it is cared for. A TJ like that Jeep should last and serve a long time with many years of fun in the future. The ability to swap in Rubicon axles from a junk yard makes it a very fun platform to build with in years to come.

My son recently learned the over rev lesson in a much less expensive way. He has been modifying small engines for minibikes and gokarts. One of his tricks this summer was removing the governor on a Tecumseh 2.5hp engine and running the revs up. He now knows plain bearings with splash oiling do not live well at high rpm heat loads. He thinks his Briggs & Stratton ball bearing engines will live better at high rpm, and he is trying porting to squeeze a little more rpm from the flat heads. I think my son’s lessons are not over, but it is cheaper than my lessons when I was turning Pontiac engines at 7200 rpm through drag strip timing lights.

Westlotorn

In my mini bike days we added stiffer valve springs and that allowed more RPM without valve float. Lost a rod once in a 5HP but that is how we learn right?

63 340HP

True.

My son has been reading and watching how to insert the 5hp valve springs in a 2hp case. With Youtube the hop up information available is amazing. If he would research and study math with the same enthusiasm, he might get somewhere a few years down the track.

He knows I worked in a lawnmower and small engine shop during high school, and has heard some of my learning experiences. I am waiting for him to ask how to grind down the base circle on one of the spare cams he has (the rpm advantage that proved real effective for speed and a short engine life).

mrg

Great hands on first time learning experience. . ..
John