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timing up camshaft with crank


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Hi, i currently have the crank at TDC and timing marks 'C' lined up as in brown repair manual. dots A and B are where the book suggests, but valves are open on #1 cylinder but closed on #6. Have I got the camshaft 180 degrees out?

When i turn the camshaft to close valves on cylinder 1 the timing mark 'C' is 180 degrees out. I'm confused.

Steve

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3 hours ago, JochemsTR said:

Steve, I use the full lift method to set my cam. You can find the method on Kent Website...

https://www.kentcams.com/support

Jochem

+1

I also use the full lift method, aiming to set the camshaft timing up to 1 degree advanced if the exact figure can't be achieved.

I would say from your photos that the cam is 180 deg out.

Nigel

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Since the cam turns two revolutions for every one of the crank, "180 degrees out" is indistinguishable from "0 degrres out", except for the timing mark. 

You will have to take this into account if you use the timing mark when you install the distributor.

Ed

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Steve,

The cam is 180 out, but the cam sprocket is correct!

You need to take the sprocket off, turn it through 180, put it back on.   Then turn both sprocket and shaft through the 180 to align the marks again.  And Bingo!   All will be well!

You will find that the No.1 valves are closed, and No.6's are both just a little bit open.    This is the basis of the Other Method, called "Equal Lift on Overlap" (QV!) which IMHO is a lot simpler!

Good luck!

John

Bl**dy tablet misspellings corrected!

Edited by john.r.davies
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I understood that the 6 gear could not be turned over like the 4 cylinder ones, The alignment with the crank would be wrong, I think you should see oilways in the outer groove of the gear, they should be facing the rear. The oil comes from the holes in the end of the cam to lube the chain.

Please correct me if I'm wrong pls.

John

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1 minute ago, John L said:

I understood that the 6 gear could not be turned over like the 4 cylinder ones, The alignment with the crank would be wrong, I think you should see oilways in the outer groove of the gear, they should be facing the rear. The oil comes from the holes in the end of the cam to lube the chain.

Please correct me if I'm wrong pls.

John

I will you can turn it you will have more settings available and you should also renew the chain 

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35 minutes ago, John L said:

NTC

I dont believe you are correct, the gears for 4 and 6 are different part numbers, and as far as I know the 6 cannot be turned over like the 4 cylinder ones can.

John 

You can believe what you like John no skin off my nose and as for some of the reply's above valves on rock is a base setting and will run .But the cam needs to be timed correctly to allow for tappet clearance etc, and do you think the punch marks was put there for the sake of it ( no) it was done to mark where it is correct for that engine.

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On this occasion I am with NTC.   Singlex cam timing sprockets are reversible, but duplex are not.

Steve,  I'm sorry you're still not right.   Start again.   Set the cam shaft roughly without the sprocket - a pair of bolts in the holes and you can turn it with a screwdriver or similar.    Then fit the sprocket, with the markings in the correcty position - the holes should line up, roughly.     Then set the timing accurately.

John

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Factory cams are symmetrical so inserting the camshaft with the first two lobes equidistant from 12:00 o'clock while the crankshaft is at TDC will get it to within a hair of where it needs to be - one of the other pair of holes in the sprocket will be close to those in the camshaft; trial fit and check for final position, adjustable via the slop in the bolt holes. I set mine to ~3 degrees advance ( crankshaft ) to compensate for stretch, but to each his own.

Tom

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9 hours ago, John L said:

NTC

I dont believe you are correct, the gears for 4 and 6 are different part numbers, and as far as I know the 6 cannot be turned over like the 4 cylinder ones can.

John

I suspect you're both correct, but mean different things! The sprocket can be *rotated* 90deg to give a 1/2 tooth change in timing. *Rotating* 180deg brings you back to where you started as the pocket has an even number of teeth. It cannot be flipped over (to show its reverse side) as the back is recessed whereas the front is not. So John's right, it can't be turned over. And Neil's right - it can be rotated. Just talking about different axes :)

J

Edited by JohnC
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