Yes you did!!

And it was a forged rod that failed. At my power level, PMR's should have been 'safe'. I guess there is no way to know the real history of these rods. I rode in the truck this engine came out of (it was out-of-control fast - ZF6 in a '97 CCLB) and I wanna say it had over 200k miles on it. Not even sure that is the rods they used?

I did have crappy tuning for the first 20k miles or so that I ran this engine engine, but its pretty hard to say that killed it.

This is why you want to machine the lip on your pistons...



I also discovered a broken rocker arm. What are the chances this failed and contributed to rod failure? (But the Smith Bro's push rod is fine!)





And the cylinder walls are smoooooth. Not much crosshatch left... The truck has been down on power and ran rough cold for awhile. I suspect the compression may have been getting low.

 

That is some good carnage! At least you had fun with it which is all the matters. Gotta love that skinny pedal!

Take your time, know you are busy. I want to check out your new vid!

 

Has this tear down given you any additional insight on any long term differences in internal combustion wear characteristics from a steady diet of WVO versus #2?

 

BFE Ky, that's 3/4's of the state. Do you remember what part of Ky?

 

I seem to remember Spencer County maybe. It was miles of winding roads out in the middle of nowhere. And i live prit near Nowhere, KY. So I know BFE.

 

Fun times Jason.

 

I need to be up and running before Christmas or we don't get to take the ski boat to Florida for our annual warm-up. (of course its probably gonna be 70* HERE today!!! )

Me and computer did not get along when I tried to make the time-lapse video and I am still holding a grudge. I should get over it soon and get this done.

Well, this engine had some unusual wear - especially considering the low mileage. It ALWAYS had a lot of blow-by and we can't really see any crosshatch on the cylinder walls and there is evidence of blow-by on the piston skirts. Since I did not put this engine together, I don't know what they did... It's possible they didn't gap the rings correctly or something? There was also some brass showing on the main bearings. This is very curious to me since I'm kinda **** about oil changes, etc.

The power has been down for the last 30k miles or so. It still ran good and had plenty of power, but it was lacking in the top end (dyno showed this too) and ran poorly/smoked when cold.

That said, I have been inside a couple of other 7.3's with over 100k miles on veggie and they showed nothing outside the ordinary for wear.

I don't remember at all!! It was a couple hours from Kirk's I think. The sellers name was Chris and he did a cummins swap in the '97 CCLB.

 

Kirk thinks it was in Spencer County which I think is in the southwest part of the state. Not near me.

 

And the new/used engine is basically ready to go in the truck. Swapped in my 175cc single shot injectors, fresh GP's, rebuilt oil cooler, swapped L99+ intake plenums, water pump and T4 mount/oil return.

If I can sort out a pilot bearing, it should go back in my truck tomorow!

Does anyone remember who borrowed my 7.3 clutch alignment tool???

 

Looks good. Hope it all works out.

 

Well, this engine had some unusual wear - especially considering the low mileage. It ALWAYS had a lot of blow-by and we can't really see any crosshatch on the cylinder walls and there is evidence of blow-by on the piston skirts. Since I did not put this engine together, I don't know what they did... It's possible they didn't gap the rings correctly or something? There was also some brass showing on the main bearings. This is very curious to me since I'm kinda **** about oil changes, etc.

The power has been down for the last 30k miles or so. It still ran good and had plenty of power, but it was lacking in the top end (dyno showed this too) and ran poorly/smoked when cold.

I looked at all the pics. Looks to me like the rod broke right where a gas rod does majority of the time. You had mentioned the rocker. I would almost be the piston crown kissed the valve and did that when the party was going on. If it was a fatigue thing it should show half broke prior, if that makes sense.

The piston crack on the crown is like anyone else and most likely the cause of the lower power if it went down to the CR. do any more look like that?

I also would bet with the beating that poor engine has taken is why you had seen the rod bearing wear. Not the veggie oil. Think about the extra loads involved racing / pulling that was way more than the rest of us hwy trucks run. It is brutal and the reason why a majority of hard core 1/4 mile guys do a tear-down and inspection/rebuild every year. Most know its a pay me now or pay big latter.

Your engine is another example of the wrist-pin area I wanted to drop some weight. That thing in my opinion is way to big and heavy. Any time you can drop weight up there you can drop more on the crank and save double in rotating mass. Not to mention it takes the load off the rods EXACTLY where yours failed. Even if a person went to a tool steel pin you could half the wall thickness and save a ton. With nearly nothing lost in capability. Also the top and bottom balance slabs on 7.3 rods are huge. Lots of material to be lost there as well. All of these things are something I was going to do here but I am a few engines behind yet in the shop. But I do want to do this. Not to mention I dont have the cash to blow on it to sit on the shelf till mine goes TU.

 

Well, the beating I have delivered is more like working a good mule and not much like hard core 1/4 mile guys. The 1/8th mile runs in my truck are like spirited drives from redlight to redlight. No boosted launches or high EGT's. The sled pulls are a little harder since I obviously don't tow in my hot tunes - but still, that is only 300ft and EGT's still never go over 1000*. My daily-driven power level was about 320HP - VERY conservative for the parts I was running (forged rods, head studs, 910 springs, chromo pushrods, etc)

I suspect the tolerances for this engine build were sloppy and perhaps the rings were never gapped correctly or something. All (8) pistons had evidence of blow-by.


The new, used engine is finally in and purrs like a fat kitten. We'll be driving to Fla (1500 miles round trip) tomorow if today's shakedown runs are successful. I'll get some more pics up when I get a chance!

 

Yo Yo hope ya'll have a fun run South. Maybe its dry down there.
Be safe. Need anything holler.

 

Depending where in Fl, it's been dry, warm (mid 80's) and humid here for the past week, and is forecast to stay this way until the weekend I believe. Enjoy, and have a safe trip!

 

Truck runs great! The oil filter is leaking at the seal. I changed the filter and it's still leaky (like 1.5 gals to get here and a mess under the truck). Not sure what else to do with that yet. I used the oil cooler off my old engine - so there shouldn't be anything wrong with that???



We are in Sebring, FL and thank God the AC is working great!!! The love bugs are out - WTH??? (If ya don't know what a love bug is, consider yourself lucky )




The kids are currently swimming at the lake cooling off after a hot day of chores helping our host do some work on the property. The water is perfect!!!