very early gear wear

[TexasKnucklehead]

I have a new chain and both sprockets, and finally have the cam to crank timing set properly. I must have turned the engine over by hand 50 times. When I went to put on the timing cover, I noticed wear marks on the teeth of the crank gear. I had to look closer to believe it. It's hard to get a good picture, but I've attached two. The top sprocket looks fine and so does the chain. Normally there would be more oil in there, but the chain is not dry and I didn't expect to see wear already. Is this normal, or should I give Moss a call -or maybe try another crank sprocket?

 

[TR3driver]

I'm not sure calling Moss will help, but I'd definitely do something. Otherwise it could wind up looking like this:

 

[bgbassplyr]

Looks like the manufacturer forgot a very important step in the manufacturing process. That gear will probably last a good five minutes with the engine running. Maybe even less. Moss should be informed, IMO.

 

[Lewis_McDorman]

Sorry to be cryptic, but if you have the Bentley manual you should read page 136.

 

[poolboy]

Sprocket alignment. That's what it looks like. The chain is shearing off the side of the teeth.

 

[TexasKnucklehead]

I do have a Bently (1976 edition), but my page 136 is an engine diagram.

But that comment and the 'alignment' hit a nerve. I know somewhere I saw where you're supposed to check the alignment of the sprockets, but can't find it now. And know I didn't do it. So I took off the cam wheel, pulled the chain, and pulled the crank sprocket and put it back on with the stamped lettering towards the engine and it looks so much better. If something can go together two ways, guess which way I do it first?

The teeth are not centered in the crank wheel.

I'm glad I noticed it now...

 

[mallard]

It's very easy to check. Use a good straight edge and put it on the flat face of the larger gear and try to slide a feeler guage under the straight edge on the smaller gear. Try to get it so you can't put a feeler under the straight edge. Make sure you keep it square. To get it correct you may have to use some shims washers behind the gear. When I took my engine apart there were two shims, with news gears it only required one.

 

[poolboy]

Yes shims or as Haynes calls them "packing washers" placed behind the sprocket on the crankshaft. See Haynes Chapter 1,Section 51.

 

[DNK]

From Bentley