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Old 08-29-2009, 08:39 PM   #1
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Default Are these rods reusable?

As the title says, getting everyone's opinion on if I could use these rods or not. Engine was dirty, clogged the oil passages, no wrist pin wire in piston #4 either. Bearings looked pretty damn bad for 3000 miles.

Anyways, the damage:

they all look pretty much like this, less scouring on the end-cap side though.
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Crower I-beam rods, it'd be nice if I could reuse them but I don't want to pull another engine hah.


And the rest of the damage:

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#2
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#3
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#4
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was cause by:
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head looked bad, looks like mix of coolant and oil. weird thing was that the drained oil looked fine, go figure:
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Time to build another engine, I think I'm going to try to get as much work done it while its in the hands of a professional during assembly, everything reworked, acid bathed, oversized pistons, acl bearings, knife-edge crank, anything else I can think of between now and then hah. Wish me luck!

Any feedback is welcome just reaching out for advice and yes this was the short block that rogezeus2003 was selling 3 months back :(
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Old 08-29-2009, 09:32 PM   #2
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If you have to ask, the answer is no. The only reusable parts from a motor like that are the block, if you're lucky, and the crank, if you're lucky.
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Old 08-29-2009, 10:45 PM   #3
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Thats not entirely true at all. Rods will often have marks like that even when disassembling a healthy motor. If the rods have no color change or blueing from extreme temp, and both the big and small end are not out of round then they should be fine.

Those pistons on the other hand look like they have a fair amount of scuffing above the skirts.
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Old 08-29-2009, 10:49 PM   #4
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Yeah, I'm thinking that so long as the bearing didn't spin in the rod, they're probably ok. Take 'em to a machinist and use an inside mic to make sure they're still perfectly round and within spec, get some new bolts, and stick 'em back in.

How'd the cams fare?
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Old 08-29-2009, 11:45 PM   #5
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how was the engine"dirty"? did you not change the oil when you got the motor? where there any warnings? low or no oil pressure?
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Old 08-30-2009, 12:08 AM   #6
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Originally Posted by Savington View Post
If you have to ask, the answer is no.
Exact words I was going to use, but you have already said so. I learned that the hard way a long time ago.

So what exactly happened, I guess I missed it. If the pistons have that kind of damage, there could be unseen damage to the rods. Just because it looks good doesn't mean it is, of course.
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Old 08-30-2009, 01:38 PM   #7
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Dude just take it to a machinist and get either a sure Yes or No
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Old 08-30-2009, 02:50 PM   #8
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Quote:
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Rods will often have marks like that even when disassembling a healthy motor. If the rods have no color change or blueing from extreme temp, and both the big and small end are not out of round then they should be fine.

Those pistons on the other hand look like they have a fair amount of scuffing above the skirts.
+1 on that... rods often have those sort of markings. If they were stock (ie cheap) rods I'd say pitch em but given they're aftermarket pieces I'd 2nd or 3rd the recommendation to take them to a competent machine shop and have them checked and use them if they check out ok.

Pistons ARE toast though... they'll make lovely paperweights.
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Old 08-30-2009, 03:04 PM   #9
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Yeah i'll run them to a local machinest to get measurements. The engine literally had dirt in the passages and I tapped the oil pan incorrectly. Even though I did it step by step on the phone with fm
:(. But there was all kinds of **** in the oil pan, lots of shavings, a peice of red rubber, hell even a blue crimp was in there. Next time I'll limit the number of people helping me to two instead of five.

Wanted to tap the oil pan when it was off but my friends put it on the block when I was waiting for the drill n tap.
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Old 08-30-2009, 03:13 PM   #10
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Does the piston skirt really have to be in perfect condition? I always thought the skirt was for structural integrity and the rings did the sealing. The block must be pretty fucked up in the process of causing that anyhow.

If you are going to have a shop do the work, just take the block and parts in and they will let you know what can be done with what you have.
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Old 08-30-2009, 03:18 PM   #11
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Yeah i'll run them to a local machinest to get measurements. The engine literally had dirt in the passages and I tapped the oil pan incorrectly. Even though I did it step by step on the phone with fm
:(. But there was all kinds of **** in the oil pan, lots of shavings, a peice of red rubber, hell even a blue crimp was in there. Next time I'll limit the number of people helping me to two instead of five.

Wanted to tap the oil pan when it was off but my friends put it on the block when I was waiting for the drill n tap.

Crank looked ok but I'll run it to a local machinest as well. I've got an extra block that I can use, it's a 97 and this one was a 94 so I'd need to get a longer oil feed. But that's the least of my worries right now lol.
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Old 08-30-2009, 05:18 PM   #12
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When I drilled and tapped my oil pan, I greased the bit, used a vacuum, and changed the oil immediately after to make sure that crap didn't mess with my engine.
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Old 08-30-2009, 08:12 PM   #13
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Quote:
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When I drilled and tapped my oil pan, I greased the bit, used a vacuum, and changed the oil immediately after to make sure that crap didn't mess with my engine.
I did too :(
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Old 08-30-2009, 08:25 PM   #14
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Quote:
Originally Posted by akaryrye View Post
When I drilled and tapped my oil pan, I greased the bit, used a vacuum, and changed the oil immediately after to make sure that crap didn't mess with my engine.
My second time around, i didn't even change the oil. Actually left the oil in and had no issues. This was on a junkyard motor that i care close to nothing about tho. Would never do that to a built engine..
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Old 08-31-2009, 11:14 AM   #15
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How'd the cams fare?
Lack of oil to the back of the head put flat spots on two of the lobes on the exhaust cam in my 99-00 head :(. Looking for an extra exhaust cam now.
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