4th Cylinder No Compression

YoshiBolo · 12-15-2017, 03:27 PM

Anyone seen this with their cylinders before? I didn't over rev the car, now sure how this happened.

BayE30 · 12-15-2017, 03:45 PM

Whats the problem?

YoshiBolo · 12-15-2017, 03:49 PM

No compression in the 4th cylinder.

Duk996 · 12-15-2017, 04:36 PM

Quote:

Originally Posted by YoshiBolo

No compression in the 4th cylinder.

Like zero? Bent valve or something. Nothing in those pics looks too bad. Not sure if that much carbon is normal or not...

roastbeef · 12-15-2017, 04:46 PM

Is it normal for any of them to look all caked up like that?

YoshiBolo · 12-15-2017, 04:54 PM

Quote:

Originally Posted by Duk996

Like zero? Bent valve or something. Nothing in those pics looks too bad. Not sure if that much carbon is normal or not...

No valve problems. Zero compression after the oil is vacuumed out but there is an oil leak somewhere.

tlow98 · 12-15-2017, 05:17 PM

Zero is a very small number and is not reflected in these pics...

Unless there are no rings, but looks pretty well centered int he bore...

BayE30 · 12-15-2017, 06:11 PM

looks like HG failed from the pattern of carbon blown off the piston on the inside edge.

almost every motor I have ever opened up had this much carbon inside.

YoshiBolo · 12-15-2017, 07:01 PM

zero compression. So its the movement of the piston head from the front and back of the engine. Does not think its a bent rod because the piston goes all the way up.

pbonsalb · 12-15-2017, 08:48 PM

Looks ok to me. Bad head gasket? Issue with valves?

jcolley · 12-15-2017, 09:18 PM

Check for a broken valve spring. Fairly common on the S85 and usually no PTV contact.

deansbimmer · 12-16-2017, 06:49 AM

You ought to pull the piston out and inspect the wall and the rings. As I mentioned in your other thread about this, the cylinder looks washed out leading me to believe the injector may have failed. That may also line up with your pre-failure symptoms you mentioned.

Bottom line is there's not enough info from four pics to diagnose an engine failure.

YoshiBolo · 12-16-2017, 08:20 AM

Quote:

Originally Posted by deansbimmer

You ought to pull the piston out and inspect the wall and the rings. As I mentioned in your other thread about this, the cylinder looks washed out leading me to believe the injector may have failed. That may also line up with your pre-failure symptoms you mentioned.

Bottom line is there's not enough info from four pics to diagnose an engine failure.

Thanks deansbimmer. Thank you for the engine contact as well. I will ask him to do that.

TomHudson · 12-16-2017, 11:38 AM

Quote:

Originally Posted by jcolley

Check for a broken valve spring. Fairly common on the S85 and usually no PTV contact.

This

GMWNashville · 12-20-2017, 12:38 PM

Much more common to see a broken valve spring as mentioned above...having zero compression is HIGHLY unlikely to be caused by washed out rings or even cyl wall damage as that would just cause very low compression.

LVI · 12-21-2017, 12:22 PM

Quote:

Originally Posted by YoshiBolo

Thanks deansbimmer. Thank you for the engine contact as well. I will ask him to do that.

any updates? i've been following this from the general forum so i'm curious what you ended up finding.

YoshiBolo · 12-21-2017, 04:49 PM

Quote:

Originally Posted by lawrence1

any updates? i've been following this from the general forum so i'm curious what you ended up finding.

Mechanic will be sending video of the movement of the piston in the next few days. Pretty much he said there is something wrong with the bottom of the block under the piston that is causing non-normal movement of the piston at the bottom of the cylinder which has caused a ring malfunction and is causing the zero compression. He said the bottom portion of the block is useless but I should be able to resell the top portion.

pbonsalb · 12-21-2017, 07:07 PM

There are more upper ends for sale.

deansbimmer · 12-21-2017, 07:40 PM

Quote:

Originally Posted by pbonsalb

There are more upper ends for sale.

No kidding I’ve got like sixteen heads on the shelf. I can barely give them away.

12-15-2017, 03:27 PM	#1
YoshiBolo Private 25 Rep 55 Posts Drives: 2008 E93M White Join Date: Dec 2017 Location: LA, CA iTrader: (0)	4th Cylinder No Compression Anyone seen this with their cylinders before? I didn't over rev the car, now sure how this happened. Attached Images Last edited by YoshiBolo; 12-15-2017 at 05:35 PM..
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12-15-2017, 03:45 PM	#2
BayE30 Lieutenant Colonel 1354 Rep 1,881 Posts Drives: 2011.75 E90 M3 ZCP Join Date: Jul 2014 Location: San Francisco iTrader: (5)	Whats the problem?
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12-15-2017, 03:49 PM	#3
YoshiBolo Private 25 Rep 55 Posts Drives: 2008 E93M White Join Date: Dec 2017 Location: LA, CA iTrader: (0)	No compression in the 4th cylinder.
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12-15-2017, 04:46 PM	#5
roastbeef Lieutenant General 11865 Rep 12,880 Posts Drives: E92 M3 Join Date: Nov 2010 Location: Orange County, CA iTrader: (4)	Is it normal for any of them to look all caked up like that? __________________ Instagram; @roastbeefmike
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12-15-2017, 05:17 PM	#7
tlow98 Major General 3414 Rep 6,263 Posts Drives: 2009 E91, 2014 F15 x35i Join Date: Aug 2011 Location: Bay Area iTrader: (2)	Zero is a very small number and is not reflected in these pics... Unless there are no rings, but looks pretty well centered int he bore...
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12-15-2017, 06:11 PM	#8
BayE30 Lieutenant Colonel 1354 Rep 1,881 Posts Drives: 2011.75 E90 M3 ZCP Join Date: Jul 2014 Location: San Francisco iTrader: (5)	looks like HG failed from the pattern of carbon blown off the piston on the inside edge. almost every motor I have ever opened up had this much carbon inside.
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12-15-2017, 07:01 PM	#9
YoshiBolo Private 25 Rep 55 Posts Drives: 2008 E93M White Join Date: Dec 2017 Location: LA, CA iTrader: (0)	zero compression. So its the movement of the piston head from the front and back of the engine. Does not think its a bent rod because the piston goes all the way up.
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12-15-2017, 08:48 PM	#10
pbonsalb Lieutenant General 7679 Rep 13,761 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	Looks ok to me. Bad head gasket? Issue with valves?
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12-15-2017, 09:18 PM	#11
jcolley Lieutenant 381 Rep 413 Posts Drives: 328 Join Date: Jul 2007 Location: Maine iTrader: (1)	Check for a broken valve spring. Fairly common on the S85 and usually no PTV contact.
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12-16-2017, 06:49 AM	#12
deansbimmer BimmerPost Supporting Vendor 4324 Rep 3,023 Posts Drives: 2011 E93 M3 Join Date: Nov 2014 Location: DFW, Texas iTrader: (17) Garage List 1988 E30 M3 [0.00] 2006 E46 M3 [0.00] 2024 X7 M60i [0.00] 2011 BMW M3 [0.00]	You ought to pull the piston out and inspect the wall and the rings. As I mentioned in your other thread about this, the cylinder looks washed out leading me to believe the injector may have failed. That may also line up with your pre-failure symptoms you mentioned. Bottom line is there's not enough info from four pics to diagnose an engine failure.
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12-20-2017, 12:38 PM	#15
GMWNashville Colonel 174 Rep 2,373 Posts Drives: 19 G05, 16 F80, 10 E70x5D Join Date: Jan 2008 Location: Nashville, TN iTrader: (2)	Much more common to see a broken valve spring as mentioned above...having zero compression is HIGHLY unlikely to be caused by washed out rings or even cyl wall damage as that would just cause very low compression.
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12-21-2017, 07:07 PM	#18
pbonsalb Lieutenant General 7679 Rep 13,761 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	There are more upper ends for sale.
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