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So any suggestions what the next step is?

There is no play when I did assemble this rod/cap with the new BE bearings and snugged up the bolts.
Well, you need to do what every engine builder does. You must measure the journal in every possible angle to make sure its round. You could also measure the con rod - you may be a REAAALLY lucky guy. If everything is within spec then sure you can reassemble, use plastigauge for one final check and be done with it. I'd say 50% chance crank is good, 90% con rod is toast.

Judging by your last statement you may not be familiar with micrometers and bore gauges. Stop by your local engine builder, tell them your story and ask them (pay if you have to?) to show you how to measure crank and bore.
 

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Discussion Starter #42
I'd think the engine is coming out for that....that's a big project. I could be wrong, maybe that is doable...without splitting the bottom end.

Could you post pics of the inside track of the vanos bearing ring? Make sure the wear is even 360 degrees. the width should be about 6mm and about 0.5 MM deep. Also, each needle bearing/roller should freely rotate.
Sorry, I'm not on the same page, are you talking about the rod bearing still or the vanos pump bearing ring?
I did not take any measurements of the vanos pump bearing ring... but I might take it apart again seeing as I might have lots of time now ( waiting for parts )
 

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Discussion Starter #43
I don't normally rebuild engines no. I work in the electrical field but I have done a lot of mechanical and rebuilt parts of engines before.. Never a Complete rebuild.
I have worked on vw's vr6 engine, 1.8 and 2.0T engines, a few of their TDI engines including the old mechanical TD, and a handfull of GM v8 blocks and one ford 302.
I have also done work to this m5 engine, with a broken valve spring on cyl 3. which i managed to change without removing the head :) luckily it was on the intake side otherwise I would have had to pull the head.

So micrometers I used once somewhere but bore guages... never. Saying that, I have used dial indicators before but I've never used a Dial Test indicator before, didn't know the difference between them and all, but... well I can use one now.
 

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Right, I remember your valve spring thread. That's why I suggested for you to learn. Had it been someone else it'd be just take the thing apart and send out the crank and con rod for inspection (also an option no?). Although most micrometers have a ratchet there's still a certain 'feel' as to how tight a micrometer should be and make sure its flat, etc.
 

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Discussion Starter #45
I will do everything I can to avoid replacing the rod and cap, and especially the crankshaft!
Right now I'm waiting to hear from Jim, is he on vacation by any chance ? anyone know?
 

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Sorry, I'm not on the same page, are you talking about the rod bearing still or the vanos pump bearing ring?
I did not take any measurements of the vanos pump bearing ring... but I might take it apart again seeing as I might have lots of time now ( waiting for parts )
No worries....just trying to save you an extra step....down the road. If the Vanos pump is already together no biggie.

You are getting a taste at these beastly things....ain't nothing fast or predictable about projects. I've always done extra or a few unanticipated things while I was in there and they've always taken twice the time I planned.
 

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Hey Rick, just got around to emails for the day and replied to yours.

I hate to say it, but that crank journal is not ok. Remember, when a bearing spins, it's due to friction, therefore heat, and galling. Galling is a welding process, meaning metal is transferred between the two surfaces. Any of the cranks I have repaired, the shop actually grinds down to get to clean, homogenous metal before weld build-up and rough grind, finish grind back to original dimension polishing to under 10 microinches Ra, and finally hardening.

The rod big end bore itself, there should be very clear diagonal hone marks on it with a surface roughness of around 50 microinches Ra.

If you are completely ok with the possibility that a further failure could permanently damage the block, you could try and and reassemble as is, but I kind of liken it back to sending a submarine to sea with a significant departure from spec. There's things that you can get by with and things you cant, and even if this was a mission critical job, I wouldn't send it. I have a few blocks with skylights in them and this is how it starts. You caught it early in the spin process at least so the likelihood of cylinder wall or other collateral damage is low. I have one block here that spun 4 bearings identical to this one and the block is still undamaged. Light honing and alusil exposure for new rings and it's good to go.

I have another that took out the #2 cylinder, cooling jacket, split a throttle actuator in half and punctured the intake plenum from below.

IMO, don't let the desire to get it running again override doing it properly. You can get the engine out in about 10 hours by yourself (I could in 7 before I had a lift, now in about 5.5 without using a lift table).
 

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Discussion Starter #48
alas the king has spoken :)
Thank you for the email as well Jim, your input is very valuable to me, and to the community when learning about our motors.
I can say that I shouldn't have waited so long to do this job, I would like to blame others and point fingers, but I always make this mistake... not listening to my gut feeling. So if any of you out there are contemplating doing your rod bearings, don't wait any longer than you absolutely need to.

Moving forward, I will try to measure the rod, cap and crank.
What really boggles me is that literally 2 days before I started this job/tread I fired up the car and ran it for about 20 minutes and moved it in my garage to get it away from the wall. During this time the motor ran fine, no noises or clunking or vibration of any kind. How could it be there is not even the slightest change in the way the engine runs (at idle/very low rpm) when you have a spun bearing?
 

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Discussion Starter #49
Gentlemen,


I have some more to share with you all, and ask for advice/opinions. This is the first time I'm using Plastigage so I am adding my results here to confirm if what I think is a okay clearance is what I have :)

I cleaned my rod and cap with brake cleaner, I dried it off with a clean rag, I then inserted a brand new set of BE rod bearings (upper is +0.0025) and bottom is stock. I put a small piece of plastigage only on top of the bottom rod/cap and placed it over the crank journal, I used my OLD bolts as indicated in ISTA, and I torqued them to spec.

I then removed my bolts and took a photo of the squashed plastigage with the metric print since the imperial is a little confusing for me (still learning it) although I suppose I could do the same thing but specs are listed in both so whatever.

Please see these photos and tell me what you think!!??
 

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Discussion Starter #50
I have one more question, it's regarding the bearings them selves. The upper ones feel very smooth when I run my finger along them. But the bottom ones have minor dimples sticking up i random spots.. You can see this in the photo above. I can feel these and I'm not sure if this is okay? Should I try to scuff it down or just leave it? Or is it a defect? Although I doubt it's a defect, all 10 bottom ones are like this.
 

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Well... you are measuring the gap across a single diameter line only. You don't know if the journal and rod bore are round. Measure using proper tools given bearings spun.

You're supposed to oil the plastigage spot so that it doesn't stick. And make sure you fully remove all of it once done.
 

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Discussion Starter #52
I am in the process of measuring in 4 different spots on the bore 0, 90, 180 and 270.
I am also doing this on cyl 5 to see what it comes up with.

I purchased a T Guage set, if I get lucky I can assemble the rod cap to the rod above the crank and measure it this way, in the motor :) , but I have to wait to get my Micrometer that does 2-3".

I will in the meantime just use a vernier with the T guage, I took time off work for this project, might as well do whatever I can with this time.
 

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Discussion Starter #53 (Edited)
You're supposed to oil the plastigage spot so that it doesn't stick. And make sure you fully remove all of it once done.
I didn't know about the oil... from the quick google search I did, it didn't mention oil. I will research more on this.

edit: the oil is to make a more precise measurement? or to hold the plastigage in place?

https://www.youtube.com/watch?v=I3GD8g0gFG0 this guy says use oil to hold in place
 

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Can you take photos of the crank journal from all angles 360 degrees? If its damaged its likely to be visible. Same for rod bore. Since each journal serves 2 cylinders just see/feel if the journal is even across both surfaces. Should be clear if overheated (bluish tint, not shiny, etc)

I created a thread when I did mine, you can compare how plastigauge looked.
 

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Discussion Starter #56
Can you take photos of the crank journal from all angles 360 degrees? If its damaged its likely to be visible. Same for rod bore. Since each journal serves 2 cylinders just see/feel if the journal is even across both surfaces. Should be clear if overheated (bluish tint, not shiny, etc)

I created a thread when I did mine, you can compare how plastigauge looked.
Not sure If i already put this photo up or not, but this is the journal, cyl 1 and 6, 6 has a small scratch looking mark, but i can't feel it with my fingernail. cyl 1 is the affected cylinder, and this is the photo of the journals with
 

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Discussion Starter #57
so far i did one more test with plastigage at 45deg away from 1st one. its exactly the same. width. however im not using a micrometer so yes there could be errors.

i will do 2 or 3 more tests then i will test cyl 6 in 1 or 2 spots.
 

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Rod cap has all signs of galling. And you can clearly see how different the journal is on the cyl that didn't spin. It has the classic blueish hue. Sorry, both have to come out.
 

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Sorry to see all this, man. :( I just dropped mine off for the rod bearing service this AM, also with BE Bearings sourced through Jim. (Thanks for the data point on the +025 TOP, btw. I was a little confused first time I saw the packaging!) Here's hoping mine comes through it OK.

For a data point, which year and how many miles on your car at the time of this service?
 

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Discussion Starter #60
Its a 06 with almost 140000kms.
I decided this is too much work for me. It will take a toll on my family time.
I am talking to a local mechanic shops who are willing to undertake this job. The intent is to pull engine out of car, remove crankshaft and have a local machine shop service the crank. mechanic will fit new rod for cyl 1 and piston rings on all 10 cylinders since they will be in there - they might aswell do it now so i dont have another surprise down the road.
I am now going to pull the battery out of car, throw the oil pan back on with only a few bolts, put the subframe all back in to get it ready for towing. I will decide on the mechanic and tow it by this weekend. i am told to expect it no sooner then 2 weeks due to maching shop.

I have this feeling that the bearings wouldn't have spun had i not started the car 2 days prior to this job in order to move it away from the garage wall.
 
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