View Full Version : Findings about Noisey v8 with scope in bad cyl #1.
bimerguycw
01-04-2007, 11:21 PM
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
01-05-2007, 01:02 AM
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?
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?
__________________
632 Regal
01-05-2007, 07:42 AM
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/PARTING-OUT-1994-BMW-740IL-E32-E34-92-93-94-M60-HVAC_W0QQcmdZViewItemQQcategoryZ6763QQihZ013QQitem Z230072961232QQrdZ1QQsspagenameZWDVW
http://cgi.ebay.com/ebaymotors/BMW-ENGINE-540-740-E32-E34-MOTOR_W0QQitemZ150050725168QQihZ005QQcategoryZ3361 5QQrdZ1QQcmdZViewItem
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
01-05-2007, 07:47 AM
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
01-05-2007, 07:51 AM
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
01-05-2007, 07:54 AM
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
01-05-2007, 07:55 AM
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
01-05-2007, 08:12 AM
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
01-05-2007, 08:36 AM
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.
Since the bore is already messed up I would give it a whack with a bottle brush hone to knock down any sharp edges and rering it. Have a good look at the spark plug & piston for signs of detonation and if present only in one cyl. start looking for vac leaks.
From here your noise sounds like it's up top, I would guess a valve hung open creating excessive lash.
It didn't seem to be shaking in the video so perhaps my vale theory is NG.
If you've got head and bottom end trouble I would call it a core and find a new motor.
brosher
01-05-2007, 11:17 AM
You can get a running used M60 for $1000. Get an new one and drop it in! :D
bimerguycw
01-05-2007, 05:15 PM
So, does this change my options for the repairs such as re-surface is easier and rebuild is more useful since it has the better block to run another 150,000 miles if rebuilt?
Bill R.
01-05-2007, 06:25 PM
an alusil block, it requires a special process to bore and hone. You can buy a oversize piston and have on cylinder bored and honed with alusil but the shop that does the bore and hone has to be familiar with the process. It takes specialize stones for the grinding process to expose the silicone in the cylinder walls
So, does this change my options for the repairs such as re-surface is easier and rebuild is more useful since it has the better block to run another 150,000 miles if rebuilt?
bimerguycw
01-06-2007, 01:02 AM
Does this mean I can have the cyl's honed in the car with heads off for possible re-conditioning so I can save labor $$$ due to removal and installation of eng/tranny?
Bill R.
01-06-2007, 11:53 AM
done in the car typically.
Does this mean I can have the cyl's honed in the car with heads off for possible re-conditioning so I can save labor $$$ due to removal and installation of eng/tranny?
BlueM60
01-06-2007, 06:07 PM
The damage you describe and the noises heard almost sounds like a case of piston-slap. This is where the piston actually becomes too small for the bore due to really worn, broken rings, improper assembly etc. Your best option IMO is to source a known good, used alusil 4.0 block from a supplier. Find one with some kind of warranty in writing. Be sure and go back with a 4.0 so youll be at least in a faster car when done. you could prob do it all for about 1500 bucks. Thats way youll knw you have a good solid engine under the hood and the job will be done right, assuming you take on the task yourself. I wouldn't bother rebuilding a block thats supposedly already been rebuilt.
PS, find the guy you got it from and see where the hell the rebuild went wrong.
-Ben
bimerguycw
01-06-2007, 08:15 PM
I any case, what cost range should I expect for a mechanic to remove and rebuilt the engine and heads?
And what's required to go from my 3.0 eng and tranny to the 4.0?
Has anyone every swapped eng/tranny in these car and have advice on the compications.
I have removed eng/tranny from my e36 325iA for frame repairs and re-installed it in my garage but really don;t want to spend that effort again unless I'm saving at least $1500 and end up with a good eng/tranny for another 80k miles.
Paul in NZ
01-06-2007, 08:42 PM
typically the 4.0 also has a bigger diff too.The 540 uses the same diff(if no the ratio) as the M5.Iresisitble force +immovable object=serious trauma for driveline parts
632 Regal
01-06-2007, 09:18 PM
you will be much better off replacing the whole assembly vs rebuilding an already pretty much unrebuildadbe scrap heap. Stick with a 3.0 instead of the 4.0, your life will be much less stressful on what is involved.
Powered by vBulletin® Version 4.2.3 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.