Feeling Cranky.... |
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Feeling Cranky.... |
wndsrfr |
Jan 12 2012, 08:04 PM
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#1
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Senior Member Group: Members Posts: 1,428 Joined: 30-April 09 From: Rescue, Virginia Member No.: 10,318 Region Association: MidAtlantic Region |
Sooo....with the P&C's off to do a simple bump up in CR with thinner shims, I
contemplated going ahead to crack the case and replace the main & rod bearings since I was this far along. Well, lo and behold, as I got the crank out it looked like one of my gray hairs had fallen down on the journal.....wait a minute, there's another one---OMG, there's cracks on this thing!! Take a look at the pics--surprising that the thing didn't let go completely! I didn't even need a magnaflux...could see them with the naked eye--I put a bit of white paint on & rubbed it off to highlight the cracks for the pics.....ain't this a hoot? Attached image(s) |
Valy |
Jan 12 2012, 08:18 PM
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#2
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Senior Member Group: Members Posts: 1,671 Joined: 6-April 10 From: Sunnyvale, CA Member No.: 11,573 Region Association: Northern California |
The nice thing about those welded cranks is that you can always predict this will happen.
Make sure you get a NEW one and not a rebuilt one. |
windforfun |
Jan 12 2012, 08:33 PM
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#3
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Senior Member Group: Members Posts: 1,779 Joined: 17-December 07 From: Blackhawk, CA Member No.: 8,476 Region Association: None |
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saigon71 |
Jan 12 2012, 08:47 PM
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#4
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Senior Member Group: Members Posts: 1,998 Joined: 1-June 09 From: Dillsburg, PA Member No.: 10,428 Region Association: MidAtlantic Region |
Man that's a rough beat...but it could have been a lot worse down the road.
I knew a guy years ago (not a bullshit guy either) who said he was still running a type 1 case that had never been split with 225K miles, top end rebuilt twice with no problems. So I thought I could get possibly get away with a top end rebuild when needed. This thread makes me think twice...unless you know exactly what's in there after 35 years. (IMG:style_emoticons/default/dry.gif) |
ThePaintedMan |
Jan 12 2012, 09:33 PM
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#5
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Advanced Member Group: Members Posts: 3,885 Joined: 6-September 11 From: St. Petersburg, FL Member No.: 13,527 Region Association: South East States |
Man that's a rough beat...but it could have been a lot worse down the road. I knew a guy years ago (not a bullshit guy either) who said he was still running a type 1 case that had never been split with 225K miles, top end rebuilt twice with no problems. So I thought I could get possibly get away with a top end rebuild when needed. This thread makes me think twice...unless you know exactly what's in there after 35 years. (IMG:style_emoticons/default/dry.gif) Yikes! Goooood save! |
SUNAB914 |
Jan 13 2012, 08:27 AM
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#6
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Senior Member Group: Members Posts: 698 Joined: 29-December 08 From: Fredericksburg VA Member No.: 9,880 Region Association: South East States |
Good info! makes me think twice about my next rebuild.
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Dr Evil |
Jan 13 2012, 05:32 PM
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#7
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Send me your transmission! Group: Members Posts: 22,995 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
Attached image(s) |
76-914 |
Jan 13 2012, 05:52 PM
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#8
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Repeat Offender & Resident Subaru Antagonist Group: Members Posts: 13,495 Joined: 23-January 09 From: Temecula, CA Member No.: 9,964 Region Association: Southern California |
Doc, your beginning to worry me. (IMG:style_emoticons/default/dry.gif) |
majkos |
Jan 13 2012, 05:55 PM
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#9
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Senior Member Group: Members Posts: 1,370 Joined: 29-February 04 From: Mile High 914 Member No.: 1,729 Region Association: Rocky Mountains |
(IMG:style_emoticons/default/lol-2.gif) |
yeahmag |
Jan 13 2012, 10:21 PM
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#10
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Advanced Member Group: Members Posts: 2,421 Joined: 18-April 05 From: Pasadena, CA Member No.: 3,946 Region Association: Southern California |
Yikes! What crank is that?
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wndsrfr |
Jan 14 2012, 08:45 PM
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#11
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Senior Member Group: Members Posts: 1,428 Joined: 30-April 09 From: Rescue, Virginia Member No.: 10,318 Region Association: MidAtlantic Region |
Yikes! What crank is that? It's an 80mm stroked VW crank with counterweights welded on....something like 5 years old but with relatively little mileage on it. 6 DE events this past summer & fall put a bit of stress on it--lets see...three 30 minute sessions per day, 13 days in all, maybe averaging 60-70mph at VIR, CMP, SUmmit Point.....maybe something like 1300 miles of HARD driving might have something to do with it, eh? Oh, yeah, something like 7000 miles on the street in the same time period....who knows? |
Jake Raby |
Jan 15 2012, 02:20 AM
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#12
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Detonation can lead to this.. It is perfectly in line with the other modes of failure that your engine has exhibited. Not saying that's the only thing that leads to this, but it is a serious contributor. The tuning issues tht plagued the car when you bought it could have been impacting the crank even before you bought the car.
We have used and sold north of 1200 of these crankshafts. Of those 2 have failed and two more have had cracks form that were caught before they failed completely. I'd like to see this one and try to force it to break to see where the weakest spot actually is. |
PeeGreen 914 |
Jan 15 2012, 03:23 AM
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#13
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Just when you think you're done...wait, there is more..lol Group: Members Posts: 10,219 Joined: 21-September 06 From: Seattle, WA... actually Everett Member No.: 6,884 Region Association: Pacific Northwest |
I bet he'd sell it to you (IMG:style_emoticons/default/biggrin.gif)
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stewteral |
Jan 15 2012, 12:22 PM
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#14
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Old Member Group: Members Posts: 384 Joined: 4-December 07 From: Camarillo, CA Member No.: 8,424 Region Association: Southern California |
Sooo....with the P&C's off to do a simple bump up in CR with thinner shims, I contemplated going ahead to crack the case and replace the main & rod bearings since I was this far along. Well, lo and behold, as I got the crank out it looked like one of my gray hairs had fallen down on the journal.....wait a minute, there's another one---OMG, there's cracks on this thing!! Take a look at the pics--surprising that the thing didn't let go completely! I didn't even need a magnaflux...could see them with the naked eye--I put a bit of white paint on & rubbed it off to highlight the cracks for the pics.....ain't this a hoot? Hey Windsurfer, To my mind, you should a VERY happy guy: you found the bad crank BEFORE it blew your engine apart!! As far as still running while broken: It's always AMAZING! I tore down a Ford 260 V8, years ago, that had 4 pistons with fractures right across the top of the crowns. When removed, they fell apart, and yet the engine ran fine before the tear-down. Sometimes the gods of engine bits smile on us. Best, Terry |
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