Cam Timing
Turbo Mini Forums

Hi

Am going to be setting my cam timing this weekend and just want to double check a couple of things:

I am going to set to TDC on number 1.
Set a protractor to 0 degrees with marker.
Turn the crank so that the exhaust rod is at the top of its travel and not the degree the protractor has turned.

Does anyone have a file I can print for the protractor as I have only got 180 degrees ones.

Which is the exhaust hole behind the number one cyclinder, is it on the left or right as you look from the front of the engine.

Does it matter what way you turn the crank, or will it just give a positve and negative reading of the same value.

Thanks

Jon

Don't use the exhaust rod!!! You use the inlet rod. The hole for this is the second one in from the right hand side of the block (water pump end). The crank rotates clockwise (looking from the timing gears end) You must rotate this in that direction!!!

i've replied to your post on tmf jon, you' find a potractor there

Its not quite that simple.. You cant really find the top of the lobe like that, you need to look at it on the way up and down again and then split the difference, same for locating TDC.


Check out my guide

http://www.terryhunt.co.uk/mini/pics/tech/picsa/pics.htm

Or Toms

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=4769

Terry

website:- http://www.terryhunt.co.uk

Ok.

So cam timing checked, need to take it off now and rebuild the engine but it seems ok.

I set to tdc by roughly aligning it, making it accurate using the DTI and then turning clockwise .007 and then anti-clockwise .007 and halfling the degrees to get it correct.

I then set this to TDC on the protractor.

I then set the DTI on the push rod (2nd in) and turned roughly to TDC, I then set with DTI. I then rotated again clockwise and anti-clockwise .007. The readings were 85 degrees and 121 so this gives me a middle postion of 103 degrees.

I think the figure is 106 degrees, (Kent 296 cam) so this is right as you need to allow 3 degrees for when you put the head on etc?

Is this right?

Thanks

Jon

why do you need to allow 3 degrees for the head??

do you mean for cam chain stretch? if so personally i wouldn't give it that much, 1-2degrees maybe.

also while your at it check the cam end float.

End float, I have heard of this but how would I check it?

I have heard you need to allow for chain stretch plus alterations when the head is all torqued up, with the rockers on the push rods etc?

Just to check is 103 the right direction from 106, or should it be 109? If you see what I mean?

Thanks

Jon

stick the dti o the end of the block so it touches the cam in the centre of the gear, then push the cam into the block and pull it out, use gentle persuasion with a screwdriver,

cant remember the tolerance of hand but its probably around 2 thou, if there is too much clearance remove some material from the back of the cam gear.

103 is the right way, as the inlet opens after tdc, the ex opens before.