Do I have worn timing chains?

[safe]

Hi
I removed my chain tensioner covers to rebuild my tensioners and this is what I found!!
Do I have worn timing chains?





As you see the chains have been flopping around hitting the case and my tensioner looks like it is nearing its maximum, at least the left one.
The chains are probably the original (one piece), but the left tensioner has been replaced by the 930 one. Right side has an older tensioner.
I belive the damage is new for I have also found traces of metal in my oil filter.

Its a bit hard to see but I can lift the chain maybee 2mm from the sprocket with the skrewdriver.

The chain ramps looks like new (when I compare them with a new).

The engine is a 2.7 -77 with 100k miles on it.

I think I remember a simular post but I cant find it.

[john walker's workshop]

combined chain and sprocket wear. when you see the left idler support lever that close to the top of the chain housing, you can assume that the right chain and sprockets are equally worn.

[safe]

Ok, I guess I can change the chain and cam sprocket, but will that do?
I mean the inner sprocket is kind of hard to get at.... I dont have the cash for a rebuild.

[Wayne 962]

John, do you think the sprockets are actually worn to the point where they are allowing the chain to slacken? It would seem that they can only wear a few thousandths of and inch, and if the sprocket wears a few thou on one side, it should theoretically only translate into a few thousands extension on the sprocket?

Chains have a tendency to stretch and wear. I would indeed replace the sprocket because the sides are showing signs of wear, but I wouldn't worry too much about the inner sprocket right now. Upgrade to the pressure-fed tensioners:

http://www.pelicanparts.com/catalog/shopcart/911M/POR_911M_911REC_pg11.htm#item74

-Wayne

[john walker's workshop]

it's mostly chain related, but sprockets wear somewhat also. replacing just the chain would definitely get the tensioner shaft back into it's normal operating range.

[safe]

Ok, I will probably replace chains and cam sprockets. Now I got to decide if I will do it myself (need to by tools for it) or not.

One more question: Where does the oil go from the chain housing? I hope it goes to the sump and then to the oilfilter so it doesn't go arount the motor with metal in it?
How does the chains get lubrication by the way?

[Jim Sims]

"It would seem that they can only wear a few thousandths of and inch".

Yes, however there are many elements to a chain and the wear on each element adds up. There is not only the wear at the locations the chain contacts the sprockets (chain wheels) but also internally at every pin and link of the chain. Chains do not stretch much (if at all) unless they are overloaded to the point of yielding. One is mostly seeing wear of the elements.

Oil goes toward the sump, then through screen around the the scanvenge pump pickup, then through the scavenge pump, then to the tank and oil filter or to the external oil cooler thermostat. Chains are lubricated by oil dragged and splashed up from the sump and intermediate shaft chain wheels.

Jim