Series Timing Questions What the heck

[bstraw]

So I have been reading the "green bible" about timing the 2.25 without front marks as I am putting in a new 2.5 cam. In a book that deals with tolerances of one thousands of inches, I am stumped at this. Please see the photo I posted at (https://picasaweb.google.com/byron.straw/SeriesTiming?authkey=Gv1sRgCMuH2fXa-JPecQ#5622407884092503026) to understand what I am talking about, you may need to click the "full screen" tab to be able to read it. Ok, here is what I do not understand; let's start with #8 in the photo. "turn the camshaft in the direction of rotation until the rocker pad has nearly opened the valve fully." What the heck, WHAT DOES NEARLY OPENED mean. How do I know when to stop? Additionally, is the point of the operation to get the #1 exhaust valve fully open? If you have a dial indicator, why would you need to go through the NEARLY fully opened option. My "nearly opened" may be different than the next guy's so how does this method make sense when you are just trying to find the maximum (open-ness) of the #1 ex. valve. Am I completely missing something here? Am I just dumb , or can I just use the dial indicator to set the #1 ex. rocker to the maximum full position and then set the crank, and then put the chain on? Sorry for the confusion but I do not want to take the front cover off after I have the motor in. I have looked at the "Land Rover FAQ" and I am still confused. Why would they say "Nearly." Ahhhhhhhhhhhh!

[Wolf Fabrication]

So I have been reading the "green bible" about timing the 2.25 without front marks as I am putting in a new 2.5 cam. In a book that deals with tolerances of one thousands of inches, I am stumped at this. Please see the photo I posted at (https://picasaweb.google.com/byron.straw/SeriesTiming?authkey=Gv1sRgCMuH2fXa-JPecQ#5622407884092503026) to understand what I am talking about, you may need to click the "full screen" tab to be able to read it. Ok, here is what I do not understand; let's start with #8 in the photo. "turn the camshaft in the direction of rotation until the rocker pad has nearly opened the valve fully." What the heck, WHAT DOES NEARLY OPENED mean. How do I know when to stop? Additionally, is the point of the operation to get the #1 exhaust valve fully open? If you have a dial indicator, why would you need to go through the NEARLY fully opened option. My "nearly opened" may be different than the next guy's so how does this method make sense when you are just trying to find the maximum (open-ness) of the #1 ex. valve. Am I completely missing something here? Am I just dumb , or can I just use the dial indicator to set the #1 ex. rocker to the maximum full position and then set the crank, and then put the chain on? Sorry for the confusion but I do not want to take the front cover off after I have the motor in. I have looked at the "Land Rover FAQ" and I am still confused. Why would they say "Nearly." Ahhhhhhhhhhhh!

That's quite common when building motors. I read that at setting the cam lobe right before it's apex on the exhaust valve. There is really no way to put a measurement on this due to varying tolerances on parts.

[kevkon]

The way to find absolute TDC is to go in one direction until movement has stopped make a mark, then rotate in the opposite direction and make a mark. Halfway between those two marks is tdc.

[slorocco]

The way to find absolute TDC is to go in one direction until movement has stopped make a mark, then rotate in the opposite direction and make a mark. Halfway between those two marks is tdc.


X2, that's how I've done it.