Help on setting the Cam Timing on AJP

[mikesr]

A couple of questions for all those who have successfully rebuilt an AJP.

I have finally got the heads on the engine and I'm at the stage of setting the cam timing.
Heads are in 'safe'mode with number 1 cylinder and number 8 cylinder on equal overlap (cam followers level).
The crank is midway between number 1 and number 2 TDC.
Timing gear is in place and the chain is draped around the cams and I'm ready to fit the sprockets and then the front cover. Before I do that I want to confirm the procedure.

So from reading the build manual I need to fit the sprockets and cover then turn crank anti clockwise until before TDC on number 2 and then clockwise to take up slack until number 2 is at TDC. Then I adjust the cam.

What isn't clear is whether the sprockets should be bolted to the camshaft before turning the crank. (The book says the sprockets should "placed on the camshaft")

I'm going to adjust as recommended by several persons with equal overlap ie with the followers level. So if I bolt the sprocket to the camshaft am I not going to move it away from that position? Then I'll have to unbolt it and move the camshaft back to where it was. How do I turn the camshaft to move it back to equal overlap?

If I don't bolt the sprocket to the camshaft I can turn the crank to no 2 TDC and then fit the bolts. Then continue clockwise through to number 1 TDC and bolt the odd bank sprocket on.

I've got issues with this approach in that the crank will be rotated through something like 30 degrees which might not be too healthy for the valves!

I may have been over thinking this but after an hour staring at the damn thing I decided it was time to consult the all knowing Cerbera forum before I do some damage.

thanks

Mike

[itiejim]

Right... The cams do need to be bolted to the sprockets before moving anything. This does mean that you will need to move the cams once you've got the crank at both TDCs. I used a long, flat metal bar with 2 short bolts in which I was able to lever the sprocket bolts with (clearly once they had been loosened).
It is a bit of a pita, but it's easier once you're actually doing it!

If you want to talk through it I have sent you a PM with my phone number.

Edit - sorry PH won't let me send PM at the moment - I'll try later.

Edited by itiejim on Sunday 14th August 21:49

[mikesr]

Thanks for that. I'll make up a sprocket turning tool before I start.

How much do the cams have to be turned? I was thinking they might need to turn so much that the bolt holes would not line up with the sprocket slots.

[itiejim]

Yes, that can be a problem... The answer is to set the sprockets at one end of their adjustable range when you set them up with the crank between the 2 TDCs - this way you have the maximum possible adjustment available to you when you need to adjust them up.

I'm afraid I can't remember which end of their extension you need to go to though...

The other way to gain adjustment if you find you have insufficient, is to take the tension off the chain, remove the cover and move the chain by a tooth on the sprocket.

[ukkid35]

If you are using the AJP8 Manual on pdf, beware that some of the pages in the Engine Timing section are not in order! This can be a little confusing to say the least.

I made the mistake of printing them out double sided which means you can't even re-arrange them in order. Sod the trees, I'm reprinting it page per sheet.

[ukkid35]

mikesr said:

Thanks for that. I'll make up a sprocket turning tool before I start.

This fits perfectly, Draper brake caliper wind back cube:

http://www.drapertoolbox.co.uk/draper-52334-38-squ...