this sucks

[dhen]

The tension pulley on my timing belt locked up, and this was the result:





The engine was just rebuilt 800 miles ago. Fortunately, I still have a warranty from the machine shop that did the work.

On another note, can this cylinder head be saved or do I have to find another core?

[boost_boy]

Get another head, man (take my advice). Whoever put the tensioner on put too much tension on the tensioner itself. In all the CAs I've ever seen, owned or built, I've never seen this before. I've had noisy tensioners, but never this "wow". Make sure you use a magnet to remove metallic debris from the cylinders as well.

Dee

[dhen]

Get another head, man (take my advice).

Dee

I was afraid of that. It was a 4-port head, too, but I have an 8-port head left over from before. You wouldn't happen to have an extra bottom half of an 8-port intake manifold that you could sell me, would you? I believe that part is different than the 4-port.

Thanks,

Darian

[ca18detgabby]

holy shiz. thats crazy.

sorry to hear that.

[themadscientist]

I thought this would be a taylor swift thread. I wish it had been, that's just horrible.

I hope this becomes the first series of pictures in a set six months from now where you have a good motor running again and you can say "this is what I started with." That's about the worst valve vs piston collision I have seen.

[float_6969]

Yea, this is bad. As Dee said, I've NEVER seen or heard of a tensioner lock up and shred a belt before, NEVER.

Actually, I've never seen a CA smack valves so bad it broke the heads of the valves off either. Usually the belt just jumps a couple of teeth and bends the valves.

The head is toast, sorry man.

[boost_boy]

I was afraid of that. It was a 4-port head, too, but I have an 8-port head left over from before. You wouldn't happen to have an extra bottom half of an 8-port intake manifold that you could sell me, would you? I believe that part is different than the 4-port.

Thanks,

Darian

I do. I'll drop you an email.

Dee

[dhen]

Yeah, it wasn't the Christmas present I was hoping for, that's for sure. I was driving though the middle of nowhere and it just suddenly puked metal everywhere. The best way I can describe the sound is about 40 pounds of forks being dropped unto the floor from ten feet...

It's under warranty, and so far they haven't been giving me a hard time about honoring the warranty. The cylinder head and original tensioner had been sitting outside in the rain before they rebuilt the engine, but I wasn't worried about it since I figured they would replace all the parts. My guess is that they choose to keep the original tensioner.

So my forged pistons are screwed and so is the head. The block was a DE not a DET block. Should I have the machine shop build me a new engine, or should I just ask them to pay for the pistons and the head and find a new engine? It's cheaper to have them do the warranty work, but seeing what happened last time I'm not sure I want another engine from them.

Any advice? I don't even know if they'd agree to the deal, but I'd imagine it'd be easier for both of us.

I do. I'll drop you an email.

Dee

Thanks. I'm sure we can work something out.

Darian

[r34 gtr]

Sorry about your loss, but....

THAT

IS

AWESOME!!!!!

A++ carnage right there. High five for doing it right, and +1 for warranty. I would just replace the whole thing at their expense.

[themadscientist]

Engine parts sitting outside in the rain. Let's ponder that for a moment.....

Have them refund your money and take your business elsewhere. That is a travesty punishable by vice grips to the package. no reputable builder or shop would allow that to happen. With this tidbit of info, the unusual catastrophic results no longer surprise me.

[bentvalves]

dang yo that 'sumb**** got banged out

[ca18detgabby]

Engine parts sitting outside in the rain. Let's ponder that for a moment.....

what it isnt like it was going to hydrolock the motor......... whats the big deal

[bentvalves]

also on the subject of getting banged out, my roomates SR recently dropped the head of a valve and also the valve stem into the cylinder. The piston and valve then got in a fight, ripped a valve seat clean out, then together, they all made their way out the manifold into a brand new v-band hotside inlet/outlet 3076R bb turbo beating the shi* out of it on the way out

to make things even the car had been dropped off at his buddies shop for some simple maintenance type work, and the end result was like, engine parts out the exhaust n sh*t

[r34 gtr]

Greg, that sounds hilarious. I'll bet the noise it made was memorable, to say the least.

Not living at the house anymore? Moved to greener pastures?

[bentvalves]

yep next town over.

now when we come home at 2 a.m. we do burnouts up the entire length of our driveway then top it off with figure 8's where it opens up. Our neighbors really like us so far. There are 4 turbo cars that live here all externally gated except for mine.

Right now across the street there is a moose in the woods, she has been there for about 4-5 days now its pretty exciting I guess.

[ca18detgabby]

Right now across the street there is a moose in the woods, she has been there for about 4-5 days now its pretty exciting I guess.

that thing wouldnt have lasted 5 days If I was there........... it would already be dinner.

[dhen]

Engine parts sitting outside in the rain. Let's ponder that for a moment.....

Have them refund your money and take your business elsewhere. That is a travesty punishable by vice grips to the package. no reputable builder or shop would allow that to happen. With this tidbit of info, the unusual catastrophic results no longer surprise me.

Not defending the machinist, but I bought the cylinder head as a core for $25 from England. I didn't think it mattered since the head is aluminum, and I figured they'd replace everything else and clean up the head.

Sorry about your loss, but....

THAT

IS

AWESOME!!!!!

A++ carnage right there. High five for doing it right, and +1 for warranty. I would just replace the whole thing at their expense.

I guess you're right. If you're going to explode it, do it in style. Do I get hall of fame points?

Here's a closeup of the pulley. It's hard to take a good picture with my camera, but if you look really closely you can see bluing:

[Danski]

Another engine for the "skimped on the tensioner" pile aye. What a waste. I have no sympathy for people who don't replace tensioners and personally would've expected better from a shop.

Bring on the rebuild aye

[dhen]

Another engine for the "skimped on the tensioner" pile aye. What a waste. I have no sympathy for people who don't replace tensioners and personally would've expected better from a shop.

Bring on the rebuild aye

The thing is, though, tensioners rarely fail. In any case, I expected they would replace everything since I was paying them to go through the whole thing.

[Danski]

On a cost for replacement/cost of failure basis it doesn't make sense not to replace them on the same interval as your cam belt.

I don't want you to assume that I think this is in any way or shape your fault, as its defiantly not. I would have also expected them to have replaced said part.

I made a special point of telling my engine builder to replace the tension on my motor after my brothers Hilux spun one the week before and destroyed the head.

[themadscientist]

I've never had a tensioner failure but my engine has spent the last 11 years with me with belt changes every 50000k and at least one new tensioner. These motors you guys are getting are ragged out junkyard mystery motors. I know your seller told you different but when they were still available, I was competing with guys yanking them just like me but to sell to you, and they all looked like hot a**. Buyer beware, trust nothing you can't personally verify.

[boost_boy]

The thing is, though, tensioners rarely fail. In any case, I expected they would replace everything since I was paying them to go through the whole thing.

Somebody tightened the damn belt too tight. And if the tensioner was in the rain, that doesn't help either. I've heard one of my customer's tensioner making noise, but I caught it in time as he was just stopping by my house to rap with me. I've even had the opportunity to hear a failing idler pulley, but it too got taken care of befor it shat itself. A super-tight timing belt will expose the age and wear and tear on this critical parts. The way this one looks, it was already failing and the tight timing belt could've very well done it in.

Dee

[sjbsuperman1425]

i guess this thread brings this question to my mind:

how do you diagnose a bad tensioner? The FSM says to rotate it and make sure it turns smooth (ie. no rough spots).

[themadscientist]

If you haven't personally replaced it since you got it, replace it.

When you think about being a cheap a**, look at ole boy's engine again and compare costs. http://www.youtube.com/watch?v=3MR6w630meQ

[sjbsuperman1425]

i planned on replacing it, i was just wondering for future reference.

[dattodude]

My engine builder didn't replace mine after a $5000 rebuild. But they only made a horrible "I have no grease" kinda noise.

I took the old ones to 'CBC bearings' for replacements. I only had to press the carrier part into the new bearing myself. Cost half of what Nissan charge.

I suspect my engine-building deadline may have promoted some sloppy work on the part of the guy that assembles the engines. I did wait 9 months after specifying originally that I wasn't in a hurry. Whatever!, they've lost my business.

I totally agree about changing these bearings when the belt is changed. They are clearly essential to engine longevity.