metal bits in the sump

[speedo]

I have a 2.7 with no history. I have given myself several "outs" to rebuild vs run...the leak down was good, the head studs solid and I had recently torqued the rocker bolts and adjusted the valves. I was replacing the oil return (collapseable) tubes and removed the sump cover to check inside and replace the gaskets. I took the sump cover off and removed the screen. When I took the screen out I dislodged some stuff that had been trapped by the screen and when I lookd carefully, they appeared to be very small metal bits. Didn't look like bearing parts, or rings. Almost small teeth...like broken off dog ears from a trannie. What could these have come from?
I then thought that maybe they were from the tensioner idler gears, or the cam sprocket. I took off the chain covers and all the teeth on the idler gears and cam pulley looked fine.
When I took the chain covers off...I was surprised to see the mechanical tensioners converted to solid tensioners??What is with the bolt and nut instead of the stock piston/arm?

[cgarr]

Are they steel or alum?

[ajwans]

Bits from your rings?

andy

[speedo]

And they look to be too small to be rings. They are 1/8th long and tapered...beats me.

[Brant]

not as bit as I feared.
are they magnetic?

[speedo]

They do not attract each other...but individually they are attracted to the drain in the sump cover. So no, they are not magnetic. If they were pieces of a ring, that would have meant my leakdown numbers would have been poor on one(or more) cylinders...yes?

[MBruns]

They look alot like the tips of the timing sprockets, if you looked at the cam and idler, it may be the lay shaft sprockets or possibly a prev. repair that was not cleaned out. There are not many other items that look like that.
Mike Bruns JBRacing.com

[MBEngineering]

HI speedo
It may not be the timing gears you can see !!!BUT



the inter-gear chain gear that you cannot, which could be why the chains have stretched and the tensioner's have been re-worked???

only a guess, poss wrong, but then again??

regards mike

[914/6]

Worse

[Eagledriver]

Most likely the mechanical tensioners caused excessive wear on the sprokets and you are seeing the broken teeth. You are living on borrowed time.

-Andy

[speedo]

This was the culprit
Weird thing was number 6

I'm guessing that a valve or plug broke a piece off, bounced around the cylinder and caused the sprocket to shear teeth. Someone did a top end and ignored the intermediate shaft....which is why when I did the leak down...the numbers were good. Anyway...on to a 2.7 E or solex camed rebuild. Thanks for the help.

[notmytarga]

Coupla hours work - complete tear-down? You could work for motormeister.

By magnetic - I'm sure Brant meant to ask if they are 'ferrous' - meaning will a magnet pick them up. This helps to determine if they are steel or aluminum. They will be ferrous if they are from those teeth.

914/6 - thanks for the shots of the worn sprockets - mine are 9.9/10 to the right one. I'll keep them.

That combustion chamber trauma looks like it could momentarily sieze the engine and cause the sprocket trauma - but the engine would become untimed and run like crap. They may not be related. Your tensioner/sprocket system was set up to fail in a hurry with the mechanical tensioner and all - do you have pictures of the chain housing setup? The chamber bits can not easily get to the case without a hole in the piston. Like this:



This piston trauma above didn't even surprise me while driving - the exhaust smoke and general roughness did. I don't think it changed the timing - I drove for 100 miles after!

Another theoretical route for the bits from the sprocket to get to the combustion chamber or vise-versa would be through the crankcase breather.