Findings about Noisey v8 with scope in bad cyl #1.

[bimerguycw]

From earlier threads I submitted I finally got the bore scope and viewed the Cyl #1 and valves that had the low compression.

Here's the video link and photo link for reference again:
Video:
http://www.youtube.com/watch?v=m54s5SmC25k

Photos of valvetrain camshafts Bank 1 through 4 cyl:
http://cw332.photosite.com/BMWValvetrainphotos/

Using the bore scope and rotating the camshaft for valves I found that Cyl # that had low compression 88 psi vs 180 psi in other 7 cyls had scoring along cyl wall (in stroke direction...up-down) as compared to the other cyls with a smooth, polished finish and zero scoring/scratches. Piston head appears undamaged and similar to other good cyls.

All valves, exh and intake, appear clean on flat surface and shafts...no visible damage like burning, pitting, rough edges from interference.

Still wondering what I can do myself to re-condition/fix this cyl rings and bore myself...any advice/experience in removing a cyl and repair would be helpful.

Still not sure how the "valvetrain" sound is involved here except that the poor compression and PCV plate vacuum problem may be influencing this sound like bad timing, etc. by ECU???

Thanks fo rthe advice comments guys.

[Kalevera]

The block can be sleeved, but it's not really worth it unless the car is getting serious forced induction treatment.

I guess there's no evidence of (anything falling) into the cylinder?

[gale]

Is it cheaper to pull the engine & strip down the block & get just 1 cylinder sleeved or just buy a new shortblock? Perhaps getting a good used Alusil motor would be cheaper? Not suggestions, just wondering. The last time I checked into sleeving all 8 bores in a Nikasil block, it turned out almost as expensive as getting a new Alusil shortblock.

Aside from that, the video sounded like a bad lifter to me but if the boroscope showed serious scoring in the cyl. wall, it could be broken rings?
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[632 Regal]

well this isnt good news at all. The guy that rebuilt the motor sucks... The only thing I would be thinking right now is where your going to score another either complete engine or short block. Make sure its the alusil block too, why take a chance. If you go complete engine its pretty much plus n play but if you swap blocks you have to contend with the cams timing, chains etc etc.

http://cgi.ebay.com/ebaymotors/PARTI...spagenameZWDVW
http://cgi.ebay.com/ebaymotors/BMW-E...QQcmdZViewItem
remember if you go 4.0 your starting another headache... isn't there anything you can do about the clown that sold this thing to you?

[bimerguycw]

I was thinking that ight be possible to minimize the labor costs and repairs needed for just the one cyl issue.

If I dis-connect the cyl 1 rod and push up through the removed head and repair rings and re-surface the light scoring walls of cyl I thought this might be likely. And have the head checked and repaired while removed.

Is this possible...has anyone done this?

[bimerguycw]

It's been 1 1/2 yrs now and I don't have the actual evidence(broken ring, etc.) in hand yet. But once I have something to point to his work I may discuss it with him just for the response and expect nothing.

Any thoughts on removing the 1 head and pushing the rod up for repair of ring and cyl and check head and repair?

[bimerguycw]

Does this upgrade require trans upgrade, or what?

Is there a procedure posted somewhere that I could be directed to for ref. on the work invovled?

Thanks for the continued advice/help guys.

[632 Regal]

you can try although if it's a nikasil block the thin coating of nik is trashed...I believe the alusil blocks do not have a coating and you might be able to get away with a light dusting of a hone, rering and hope for the best.

Now... you saw a problem, whats making all that noise? certainly isnt a ring.
I get bad thoughts whenever i click on that video....:eek:

[bimerguycw]

That's why I thought to have it removed and checked while "hopefully" being able to repair the cyl.
But if it's nikasil than is my cyl not okay to re-surface the scoring and re-ring and expect good results?

[632 Regal]

yes need the trans, not sure about driveshaft and harness. someone just posted here in the past couple weeks about doing the swap. think there was 2 conversions.