124,000 miles so far. She's been rock solid since buying her new with 8 miles. Synthetic oil since 9K with 5-6k changes every 6 months.
Oh no my Yota Threw that rod
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OVERKILL
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I don't think it is powder medal. I could be wrong however.
I also don't think it is a forging. They usually bend. I've seen a few 302's that were pushed beyond their limits, and when the block broke, and parts went places they weren't supposed to go, you ended up with some pretty funny shaped rods. The 302 had forged rods.
The Modulars have cracked powder rods (except for the Termi, BOSS 302, Shelby...etc) and when they break, they look like this. Hard to tell from the picture, but normally with a cracked powder rod, you can't tell where the rod is "cracked" between the top and bottom sections. On this rod, there appears to be a distinction where the rod and cap meet. So going by that, I would assume it isn't cracked powder either.
This leaves us with it probably being a cast item, correct? Unless Toyota used forged powder, but didn't crack it?
I also don't think it is a forging. They usually bend. I've seen a few 302's that were pushed beyond their limits, and when the block broke, and parts went places they weren't supposed to go, you ended up with some pretty funny shaped rods. The 302 had forged rods.
The Modulars have cracked powder rods (except for the Termi, BOSS 302, Shelby...etc) and when they break, they look like this. Hard to tell from the picture, but normally with a cracked powder rod, you can't tell where the rod is "cracked" between the top and bottom sections. On this rod, there appears to be a distinction where the rod and cap meet. So going by that, I would assume it isn't cracked powder either.
This leaves us with it probably being a cast item, correct? Unless Toyota used forged powder, but didn't crack it?
Ouch.
The 5vz-fe has been a fantastic engine over the years.
Very rare to see them blow up.
The 5vz-fe has been a fantastic engine over the years.
Very rare to see them blow up.
I will take some additional photos. The load on the engine I'm not sure about because my wife was driving it. She was getting onto the highway just after the on ramp. I have no reason to think it was over revved, she does not drive abusively.
You can't over-rev it unless you have a manual and grab the wrong gear.
It would just sit on the rev limiter.
It would just sit on the rev limiter.
[/quote] I was thinking I would check the compression in the donor since it came attached to a transmission with a starter. Anyone know how accurate/useful those cold engine compression readings would be? [/quote]
Cold compression readings can be useful if for nothing else than to compare the cylinders against each other. If one cyl reads substantially lower than the others you can take a look at it before you reinstall the engine. If one reads low and/or you want to use you original heads I think I'd do a quick re-ring and bearing job, just for peace of mind. I will look and see if I can find the cold compression specs for your engine. Good luck again!
Cold compression readings can be useful if for nothing else than to compare the cylinders against each other. If one cyl reads substantially lower than the others you can take a look at it before you reinstall the engine. If one reads low and/or you want to use you original heads I think I'd do a quick re-ring and bearing job, just for peace of mind. I will look and see if I can find the cold compression specs for your engine. Good luck again!
The 3VZ-FE version of this engine uses cast iron connecting rods:
http://en.wikipedia.org/wiki/Toyota_VZ_engine
It's possible that the 5VZ-FE uses the same.
http://en.wikipedia.org/wiki/Toyota_VZ_engine
It's possible that the 5VZ-FE uses the same.
I took more pictures of the bearing and the crank, I had to go to work but will post the pictures in the morning. Thanks for the kind words, again great forum here!
Justin
Justin
I was able to DL an OE manual for the 2002 4Runner and the 5vz-fe is supposed to have 174 lbs compression warm with a minimum of 145 lbs, max variance of 15 lbs. Sorry it didn't mention any cold reading. I don't have any experience with this engine so I'd hate to take a guess as to what a cold reading might be. Maybe some one on this site would be nice enough to test theirs? Or maybe on a Tacoma site?
I did not have the Pennzoil warranty, did not even know about it.
Rob- thank you for the compression readings, hopefully I will be checking it soon.
Rob- thank you for the compression readings, hopefully I will be checking it soon.
More pictures as promised, let me know what you think.
Man that sucks for such a clean engine. I could understand if there was sludge. I've heard a few 4Runners on Yota Tech having a similar issue.
OVERKILL
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That rod looks like a casting to me FWIW.
Congrats on such a clean engine! Makes working on 'em so much easier.
Those bearing inserts show remarkably little wear, so it's safe to rule out an oil problem. I think I see a little polishing where a crack may have started but it's hard to be sure. Jloy, take a look and see if you can see any polishing. It happens when a small crack starts and thru vibration and heating cycles it polishes both sides of the crack. As opposed to the grainy casting it's pretty shinny.
Merging into traffic in Raleigh... I've been there too many times and it can take every bit of power nearly anybody has just to get in. So I'm thinking traffic finished this rod off. No telling how long the crack has been there, just waiting to fail. Surprisingly it failed near home and not on the way to some vital or life-and-death situation! PM me if I can help out.
Those bearing inserts show remarkably little wear, so it's safe to rule out an oil problem. I think I see a little polishing where a crack may have started but it's hard to be sure. Jloy, take a look and see if you can see any polishing. It happens when a small crack starts and thru vibration and heating cycles it polishes both sides of the crack. As opposed to the grainy casting it's pretty shinny.
Merging into traffic in Raleigh... I've been there too many times and it can take every bit of power nearly anybody has just to get in. So I'm thinking traffic finished this rod off. No telling how long the crack has been there, just waiting to fail. Surprisingly it failed near home and not on the way to some vital or life-and-death situation! PM me if I can help out.
OP, was the engine hot or cold when the rod failed? Were you driving it hard at the time?
A coworker blew a 4I engine in his 09 Altima with only 40K miles. He doesn't know much about cars but the engine failed while he was pulling out of the parking lot. So I assume he wasn't driving hard. He saw smoke and oil coming from the engine. The dealership told him he would get a new engine under warranty.
A coworker blew a 4I engine in his 09 Altima with only 40K miles. He doesn't know much about cars but the engine failed while he was pulling out of the parking lot. So I assume he wasn't driving hard. He saw smoke and oil coming from the engine. The dealership told him he would get a new engine under warranty.
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The engine had been warm for a while, the truck was about 8 miles from home no crazy acceleration involved but my wife was trying to merge with somewhat crowded interstate traffic. I am starting to think that this rod was just a bad one.
I got my crank pulley tool made and ready to go to town. The donor motor is in the shop waiting. So I will be ordering my gaskets, picking the best heads off the two motors, and coming up with an engine!
I got my crank pulley tool made and ready to go to town. The donor motor is in the shop waiting. So I will be ordering my gaskets, picking the best heads off the two motors, and coming up with an engine!
Sounds like it is one of those freakish events that seems to happen on occasion. More than likely it is a metallurgical issue with the rod.
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