Broke a rocker on a 3 cylinder perkins.......

[Patrick]

Tractor started to miss bad yesterday, had just fired it up and started cutting weeds. Started checking stuff and found the end broke off a rocker, at the end that the adjustable cam follower comes in contact with it.
Called around yesterday, went this morning and picked up a rocker assembly at the tractor boneyard. Put it back together and it runs okay. Big question is what caused it to break? Tractor is a ford super dexta from the early 60's, had pistons, bearings, head, etc. about 15 years ago, engine looked pretty clean under the valve cover. Only runs about 20 or 30 hours a year cutting weeds (6' bush hog) and running a wood splitter.

Anyone run into this before??

[macka]

Check the rocker and see if its a bad cast (small inclusions or big bubbles) or if it work hardened and broke off cleanly. Its a rare event, but it does happen on occasion, mostly on high hour engines.

[catlin_cava]

I'm guessing the motor went under heavy loaded at a low RPM and it snapped, My dad heard of that happening, our perkins runs 30 to 60 hours a month in the winter months pushing a 6foot blower, and its from 68 and only ever had 1 motor job 10 years ago when i blew it up during haying.

[Patrick]

No major stresses on the engine, just the usual. Put the mower on it the week before and ran it for a 1/2 hour or so. Screwed up when I ran it the next time......

Tractor is about 1960 with a whole slew of hours........  Had pistons/sleeves etc. about ten  or 15 years ago.

[catlin_cava]

I've never heard of that happenin before lol

[maxfax]

I'd be willing to bet it was a flaw in the casting that just took time to make itself known....

[Patrick]

Not a cast rocker, stamped steel folded double. Tractor is from the early 60's, and has a pile of hours. Flaws should have showed up a long time ago........

[maxfax]

It should have, but not necesarily..    Oddly enough another perkin's story, the 354 Perkins in my Dad's 2-85 White was 27 years old with about 6,000 hours when a hole in the one cylinder finally made itself known..  It was right after flushing the coolant..  One would think a weak spot such as that would have made itself known alot sooner...

It may have just simply been fatigue as well..   Rockers aren;t generally replaced in a rebuild...

[Patrick]

That's bizarre. A 354 perkins is a dry sleeve engine(I've got one in my truck). Must have had a casting flaw and major cavitation to boot. Ever see the test kits for antifreeze for wet sleeve engines? It would surprise you how bad new antifreeze can be!

[maxfax]

That's bizarre. A 354 perkins is a dry sleeve engine

That it was..  Literally right after flushing and refilling it started blowing water out the exhaust..   Thought for sure it must be a head gasket..  Got the head off and saw a crack in the sleeve..    After getting the sleeve out we saw a small sand hole in the block... We discussed it with the guys at the machine shop and decided to try salvage the block..  They bored that cylinder and installed a larger sleeve then installed the standard sleeve inside of that..  So far so good...

I inherited this antifreeze recycling machine years ago..  It doesn;t work but it had a bunch of antifreeze testing gadgets with it.. One for PH, some sort of spectral analyzer, and one I have no clue what it does...  I've tested several different antifreezes and yes they are quite scarey..  The worst being GM's Dex Cool, and some other extended life  crap... Allegedly the GM stuff has been reformulated, I haven't tested it yet...