Pelican Parts Forums - how to come back and check cam timing?

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how to come back and check cam timing?

please excuse my ignorance but Im thinking that somehow i made a mistake on my cam timing and before i go any further I'd like to check it. trouble is, i can't get my tiny mind around how id set up the dial guage and crank position to get my reading (1.28 for my 964 cams)

can someone enlighten me?

thanks

The same way you set them in the first place. I don't understand your question. There are lots of pages of threads on this subject. I'm not trying to be harsh but maybe you should have someone else check them.

-Andy

Hi Andy, sorry , sounds lke a silly question I know. I timed both cams to match each other then, happy that id got them so close, put everything away and started thinking about the next steps. now, going back to the engine, i need to get the process fresh in my mind. Im assuming that when you say that 'i check my timing the same way i did it the first time' that you are saying that i need to start all over and set no 1 at tdc, back off the cam nut and set it with the dot facing up etc.... is this the only way to re check my timing? by doing it all over again?

Quote:

Originally posted by adomakin
Hi Andy, sorry , sounds lke a silly question I know. I timed both cams to match each other then, happy that id got them so close, put everything away and started thinking about the next steps. now, going back to the engine, i need to get the process fresh in my mind. Im assuming that when you say that 'i check my timing the same way i did it the first time' that you are saying that i need to start all over and set no 1 at tdc, back off the cam nut and set it with the dot facing up etc.... is this the only way to re check my timing? by doing it all over again?

No, no, you don't need to disassemble anything (unless you put the chain box covers on already).

Set the motor at TDC for #1 - just like you were going to adjust valve # 1. Your distributor should be pointing near #1 spark plug or close (but not exactly on) the faint mark on the distributor for #1.

Check that the valve clearance for #1 intake is .1mm/.004".

Tension the idler arm in the same way you did when you set the cam timing originally. The tensioner alone is not sufficient.

Put Z block and indicator on #1 intake with the tip of the dial indicator on on the top of the valves spring retainer. Adjust the holder so the dial indicator tip is pressed in ("preloaded") 5-10mm.

Note the dial indicator setting or zero it if possible (digital indicator).

Turn the crank one revolution i.e. 360 degrees right back to the TDC mark on the pulley.

The dial indicator should now have your the cam setting value.

Rinse and repeat for #4.

Is it coming back to you now?

-Chris

how embarrasing! thanks chris. Andy, maybe you are right!

I agree with what Chris says except I think you don't have to increase the tension on the chains. You can do this check with the chain covers on. You may get a slightly different reading than before but you are just checking to make sure you did it right the first time.

-Andy

Quote:

Originally posted by Eagledriver
I agree with what Chris says except I think you don't have to increase the tension on the chains. You can do this check with the chain covers on. You may get a slightly different reading than before but you are just checking to make sure you did it right the first time.

-Andy

You could be right Andy. You'll get a different value but it might be good enough for a sanity check. I'd be leary about doing it with hydraulic tensioners that aren't pumped up and "solid".
-Chris