TOPIC:

Update chain slack
i have two primary chains, 1 out of my A5 and the 1 out of the ZG.
i have tried both chains connected between the crank and primary shaft

chain one had 18mm of vertical play measured between the crank and primary shaft. this equated to 3 degrees of rotation on the crank
chain two had 21mm of vertical play measured between the crank and primary shaft. this equated to 4.5 degrees of rotation on the crank
add onto this the possible amount of stretch on the cam chain then the valve timing will be retarded as john explains above.

kwak1261 wrote: Update chain slack
i have two primary chains, 1 out of my A5 and the 1 out of the ZG.
i have tried both chains connected between the crank and primary shaft

chain one had 18mm of vertical play measured between the crank and primary shaft. this equated to 3 degrees of rotation on the crank
chain two had 21mm of vertical play measured between the crank and primary shaft. this equated to 4.5 degrees of rotation on the crank
add onto this the possible amount of stretch on the cam chain then the valve timing will be retarded as john explains above.

Hmmmmm.......... 18 mm of slop in the chain and only 3.5 degrees of crank rotation?? Something's not sounding right there. Think about it. How much would you have to turn the crank to lift the chain 18mm? When I pull my engine to replace the chains I'll take the service manual's reading. I've got 12 degrees of crank rotation right now so if your measurement is correct then I should be seeing my primary chain dragging in the bottom of the oil pan?
I'm wondering if when you did your check possibly all the slack was not at the top or the bottom? Just a thought. I'm thinking that 3.5 degrees of crank rotation might be around 5or 6mm of chain slop.

LEDKZ1300 is in the perfect position to verify this info. I see he has the engine split and Lots of slack in the chain. Perfect time to see how much crankshaft rotation it takes to remove the slack. Up for the task Bud??

i am only talking slack between the crank and the primary shaft.
the new chains arrived today so i can install the first chain and see what we have.
ill keep you posted.
the first pic shows the amount of slack in the chain and the dial gauge reading 25. if you lift the middle of the chain to its max that gives you 18mm of slack total. now rotate the crank to take up the slack as shown in pic 2 and the dial gauge reads 22
now when i went to school 25-22=3 or am i doing it wrong ?????





and the new chain in place only 3mm of vertical play and zero movement on the crank

I think I would have held the secondary shaft steady and rotated the crank back and forth to take the measurement. but you've got the new chain in now so..........

Glad you got a chain !!

Kawboy wrote: I think I would have held the secondary shaft steady and rotated the crank back and forth to take the measurement.!!

I did, if you look to the right behind the piece of paper there is a clamp on the secondary shaft holding it steady while i rotated the crank back and forth. thats how i got the measurement of 3 degrees on the dial gauge, we'll have to wait and see what you find when you get your engine in bits.
and if you look at the dog teath on the end of the secondary shaft you will have noticed that they havent moved in relation to the case mating surface either.