Found all the missing pieces in an oil passage....pics

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05-29-2007, 12:50 AM

Big Dave

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Found all the missing pieces in an oil passage....*pics*

After a nice weekend in Vegas, I spent a little time in the garage tonight. I took off the head and found all this good stuff crammed into the oil return passage...

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05-29-2007, 12:52 AM

Big Dave

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Spark plugs look good. Here's what the broken head looks like versus an intact version.

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05-29-2007, 12:54 AM

The DareDevil

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Wow. It looks like they were placed neatly for you to find!

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05-29-2007, 12:58 AM

V2Rocket

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****...what the hell happened? Broken chain?

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05-29-2007, 01:01 AM

the flyin' scotsman

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what caused the head to fracture? Did the tensioner sieze?

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05-29-2007, 01:01 AM

Big Dave

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Quote:

Originally Posted by V2Rocket_aka944

****...what the hell happened? Broken chain?

Nope. Chain is fine. The cylinder head broke where the tensioner was mounted. The tensioner came completely free, along with various other bits and pieces. Timing was not affected (no valve-to-piston damage).

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05-29-2007, 01:04 AM

Big Dave

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Quote:

Originally Posted by the flyin' scotsman

what caused the head to fracture? Did the tensioner sieze?

I don't know for sure. Other than being chewed up by the camshaft gear teeth, it was intact. It could have seized, but I don't know how or why. I had a low oil pressure situation earlier in the day (dropped to just below 2 bar at idle and gradually went back up once traffic started moving), so I have to assume it's related.

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05-29-2007, 01:04 AM

V2Rocket

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But you're screwed for one head.

Guess its time for some stage-3 racing heads...

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05-29-2007, 01:06 AM

Big Dave

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Quote:

Originally Posted by V2Rocket_aka944

But you're screwed for one head.

Guess its time for some stage-3 racing heads...

Nope. The intact head in my picture is the replacement. Lots of cleaning to do. I'll have some valves/lifters for sale soon, assuming they check out OK.

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05-29-2007, 01:12 AM

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the flyin' scotsman

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Dave.........you did work on his engine recently; did you re-mount the tensioner? If everything else is good then the problem happened at the tensioner or a head fracrure........unreal!

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05-29-2007, 01:18 AM

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Chris

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Exactly what happened to mine when the tensioner pad broke, evidently the same thing happens to 944 and 968's i.e. the mounting point for the tensioner breaks. I feel for you and good job for not getting too discouraged.

I found small fragments all the way to the oil pump but none further on (I split the block just incase), unlike our 4 banger bretheren the 928 continues to run on 4 cylinders which only helps ingest the debris.

Chris

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05-29-2007, 01:55 AM

#12

Big Dave

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Quote:

Originally Posted by Chris

Which pad? The thicker top pad didn't break. The bottom, flat pad broke the edge off but not where the chain made contact.

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05-29-2007, 01:55 AM

#13

Big Dave

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Quote:

Originally Posted by the flyin' scotsman

Dave.........you did work on his engine recently; did you re-mount the tensioner? If everything else is good then the problem happened at the tensioner or a head fracrure........unreal!

Yes, I re-mounted the tensioner. Eveything was torqued to spec.

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05-29-2007, 03:44 AM

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Bill Ball

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Man, Big Dave, that's a load of junk. I'm almost surprised you didn't find some old coins, a few pertrified french fries and a wedding ring down there.