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rsfruitbat · Posted: Wed Sep 26, 2007 7:27 am Post subject: 16V crank cam drive pulleys

Got loads of 16V bits but never actually took one apart. Just begginning to build engine up now and have noticed that cambelt drive cogs have a concave face, and a flat face Sad

. I am guessing that the cog nearest the crank nut has to go on flat face in, else there isnt much to drive on the Woodruff key. However havent got the foggiest idea if I am right or how the inner cog is orientated Crying or Very sad

.

Can someone please clarify this for me Confused

.

Also is the front engine casting different on the 16V as cogs are broader?

Thanks RSfruitbat

tvatavuk · Posted: Wed Sep 26, 2007 3:28 pm Post subject:

What is cog? Hope picture is helpfull.

_________________
Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

rsfruitbat · Posted: Wed Sep 26, 2007 5:12 pm Post subject:

From the crankshaft at the front in sequence there is:

nut
pulley spacer
pulley
COG
belt shield
COG
belt shield

It is the crank driven COGs that take the drive via the belts out to the camshaft pulleys / cogs.

Unfortunately the photo doesnt show what I am after. You can only see what I mean if you have the COGs off the crank in front of you.

RSfruitbat

Alan · Posted: Wed Sep 26, 2007 8:46 pm Post subject:

Now i would like to know what is COG Question

I have built a lot of 33 engines but my english is poor so i dont understand what do you mean.

rsfruitbat · Posted: Thu Sep 27, 2007 7:24 am Post subject:

In this instance I am calling a COG the round piece of metal with teeth that is used to drive the belt.
The belt then in turn rotates the camshafts. On the end of the camshafts is another COG but people tend to call tthem pulleys.

RSfruitbat

tvatavuk · Posted: Thu Sep 27, 2007 9:32 am Post subject:

Ok now after that nice first illustration I know what is cog.
I remember having same problem which I solved by looking at beltshields and how they were worn. Unfortunatly I have no recolection what was orientation of those now Sad

Alane - toothed wheel on crank shaft that moves cambelts.
_________________
Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

john 33_16v · Posted: Thu Sep 27, 2007 10:51 am Post subject:

Hi,

Scroll down about 10 topics to Bobbbers post- ''What's wrong with these photos''

Not sure if those pics help??

John
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08 Fiat Grande Punto Exotica Red
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rsfruitbat · Posted: Fri Sep 28, 2007 7:33 am Post subject:

Had a look at Bobbbers posts but the crank pulley hides the cogs I am on about. Thanks though.

RSfruitbat

tvatavuk · Posted: Fri Sep 28, 2007 10:42 am Post subject:

These are cogs Smile

(picture of Alans engine buildup) Still not help for orienting them I know. But it should make clearer to people what it is.

_________________
Tino Vatavuk
Little black dress which replaced Alfa Romeo 33 S 16v Permanent 4 GMo

rsfruitbat · Posted: Fri Sep 28, 2007 1:28 pm Post subject:

Thanks for that Very Happy

. The picture identifies exactly the pulleys / cogs I mean.

RSfruitbat

Alan · Posted: Fri Sep 28, 2007 10:29 pm Post subject:

The inner cog goes with flat side first, so it leans onto the edge of the crankshaft. If you would mount it with concave side first, then it would bent the washer when thightning the nut.

rsfruitbat · Posted: Sat Sep 29, 2007 6:31 pm Post subject:

Thanks for that Alan. Any idea on the outer cog?

RSfruitbat