Re: Dodged a bullet; vibration found - not good (w/ pics)
[Re: Guitar Jones]
#1364454
01/05/13 01:30 PM
01/05/13 01:30 PM
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Joined: Jun 2003
Posts: 52,972 Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
That #2 main bearing lost it's form due to overheating probably from lack of oil judging from the photos.
Heat caused the bearings to loose the crush... it could be the crank wasnt straight being that its the one set... but there was dirt in there and it happened on the first fire up
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Re: Dodged a bullet; vibration found - not good (w/ pics)
[Re: StealthWedge67]
#1364455
01/05/13 02:01 PM
01/05/13 02:01 PM
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Joined: Mar 2007
Posts: 3,298 West Coast, USA
jbc426
master
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master
Joined: Mar 2007
Posts: 3,298
West Coast, USA
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What the experts above said, and don't forget to clean your rocker shafts out with the brushes too.
1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's 1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)
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Re: Dodged a bullet; vibration found - not good (w/ pics)
[Re: Bad340fish]
#1364456
01/05/13 02:18 PM
01/05/13 02:18 PM
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Joined: Mar 2008
Posts: 5,746 Ontario, Canada
Dodgem
master
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master
Joined: Mar 2008
Posts: 5,746
Ontario, Canada
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Quote:
Quote:
A guy that works in my garage behind the house did the same thing!
Love it, that guy screws my stuff up sometimes also lol
You know what I've learned from my mistakes???
It's that I maker lots of mistakes!
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Re: Dodged a bullet; vibration found - not good (w/ pics)
[Re: VernMotor]
#1364459
01/05/13 09:31 PM
01/05/13 09:31 PM
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Joined: Feb 2009
Posts: 1,532 off the grid
340B5
pro stock
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pro stock
Joined: Feb 2009
Posts: 1,532
off the grid
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I still remember in the engine building class; the instructor said "clean it, and then clean it again and then when you're done, clean it again.
Yeah, it's got a smallblock.
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Re: Dodged a bullet; vibration found - not good (w/ pics)
[Re: Performance Only]
#1364460
01/05/13 09:41 PM
01/05/13 09:41 PM
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Joined: Jan 2003
Posts: 6,591 Canton, Ohio
Sport440
master
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master
Joined: Jan 2003
Posts: 6,591
Canton, Ohio
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Quote:
There's certainly a lot of trash in the bearings, but I think some of you are really overlooking the obvious cause of failure. Take a good close look at the wear pattern on those mains and think about it.
Okay,
Boy , I see lots of stuff.
1. Lots of trash in the oil. 2. Uneven wear patterns. 3. Wear at the parting lines. 4. Heat build up burns from lack of oil. 5. Apparent crank contact on all bearings.
Those are the symptems that I see, so what do they mean.
My guess.
Combined issues, trash in the oil main bearing bores out of round bearing clearences to tight lack of oil flow at some point maybe poor assembly with grit on back of bearings any or all of the above
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Re: Dodged a bullet; vibration found - not good (w/ pics)
[Re: Sport440]
#1364463
01/05/13 10:19 PM
01/05/13 10:19 PM
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Joined: Jul 2010
Posts: 2,091 Delray beach, Florida
Performance Only
top fuel
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top fuel
Joined: Jul 2010
Posts: 2,091
Delray beach, Florida
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Quote:
Quote:
There's certainly a lot of trash in the bearings, but I think some of you are really overlooking the obvious cause of failure. Take a good close look at the wear pattern on those mains and think about it.
Okay,
Boy , I see lots of stuff.
1. Lots of trash in the oil. 2. Uneven wear patterns. 3. Wear at the parting lines. 4. Heat build up burns from lack of oil. 5. Apparent crank contact on all bearings.
Those are the symptems that I see, so what do they mean.
My guess.
Combined issues, trash in the oil main bearing bores out of round bearing clearences to tight lack of oil flow at some point maybe poor assembly with grit on back of bearings any or all of the above
Most everybody just assumes it's a lack of oil. It may or not be. Take a look at the wear pattern on the mains all the way up to the parting line. given that there's at least .003" of ecentricity built into the bearings, that tells me right away there was insufficiant oil clearance. A good portion of the trash may have very well come from the bearings. I'll say this also, when a machinist finishes working on your stuff, they typically clean the worst of the debris from it whether it be a block or a crankshaft or most anything else. They don't clean and prep it for final assembly unless you specifically ask them to do it. That type of cleaning generally comes with an additional charge. It's up to the person assembling the engine to make sure everything is spotless and ready to go. When you see a bearing into the copper it was either starved for oil or had no oil clearance to start with. Since the rod bearings don't seem to be into the copper, my guess goes back to lack of oil clearance on the mains. It's pretty obvious the heat on that one bearing caused it to lose its temper and it wouldn't surprise me to see a slightly bent crank and signs of bluing as well. The block needs to be closely inspected and probably align honed or bored again. (I prefer boring over honing) Just because a block is align-honed and the crank was ground does not mean oil clearance is automatically okay, nothing could be further from the truth, actually. I have teo engines in the shop right now that look alot like the OP's. One was built by a local machine shop with less than 5000 miles on it and the other by the owner with ZERO miles on it, just cam break in time. My best advice would be to take nothing for granted when it comes time to put it back together. Enlist the help of a competant machinist to cage the bearings and measure, or at the very least, someone with the right tools and the experience necessary to do the job right. You can't have any engine part too clean, so when you think you got it spotless, clean it again. Best of luck.
machine shop owner and engine builder
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Re: Dodged a bullet; vibration found - not good (w/ pics)
[Re: Performance Only]
#1364465
01/05/13 10:58 PM
01/05/13 10:58 PM
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Joined: Jul 2006
Posts: 4,319 Puyallup, WA
StealthWedge67
OP
master
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OP
master
Joined: Jul 2006
Posts: 4,319
Puyallup, WA
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Thanks for all the help in understanding this, guys. I would maintain that if exessive crud got into the bearings, it came from inside the oil galleys, as I did not clean them upon assembly. I did, however make sure that all surfaces were clean, clean, clean. I may have missed something, but I am pretty confident about the cleanliness of my assembly (outside of the oil galleys). The main bearing clearances were measured at .0018 - .0022 with plastiguage. This jived with what the machinist told me he worked to, which was .002. I realize this is a little tight for a race motor, but well within specs for a street motor. It did spin freely by hand on the snout upon install. In an effort to make sure I check every detail this time, I just purchased some tools online. I have a bore guage indicator, and a set of micrometers on the way. I already have a dial indicator with a magnetic base and a bridge base. I should be tooled up to check every detail this time.
Last edited by StealthWedge67; 01/05/13 11:42 PM.
LemonWedge - Street heavy / Strip ready - 11.07 @ 120
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Re: Dodged a bullet; vibration found - not good (w/ pics)
[Re: StealthWedge67]
#1364471
01/06/13 04:31 AM
01/06/13 04:31 AM
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Joined: Jan 2003
Posts: 27,421 Balt. Md
383man
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 27,421
Balt. Md
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Quote:
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Just glad to see you found it before it got worse and did any more damage. Ron
Me too, Ron! I may be slow, but I'm learning. I'm very glad I heeded my own better judgement and tore into it when I felt something wasn't right.
It is also a good feeling when you find and repair your problems yourself. And its even more rewarding when its with a super fine Mopar like yours. Ron
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Re: Dodged a bullet; vibration found - not good (w/ pics)
[Re: southernman]
#1364473
01/12/13 11:27 PM
01/12/13 11:27 PM
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Joined: Jul 2006
Posts: 4,319 Puyallup, WA
StealthWedge67
OP
master
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OP
master
Joined: Jul 2006
Posts: 4,319
Puyallup, WA
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The crank is going to the machine shop Monday where I'll specify it to be checked for straight and magnafluxed. If it checks out okay, I'll have it refinished and then re-assemble. If it has issues, I'll start from scratch, perhaps look at a "source" crank this time.
LemonWedge - Street heavy / Strip ready - 11.07 @ 120
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