When to replace timing chain

IHi, i want to know when to replace timing chain on my 74-250ci maverick

 

i believe that the 250 uses timing gears. so you should have no chain to change.

 

Oh, there's a chain...

 

yes. my car use timing chain

 

this is not a timing "belt" like the newer japanese cars use, which go out at 90,000 miles and destroy your engine.

i have honestly never heard of a timing chain breaking, even though I know it has happened.

I replaced mine, with a double roller and USED sprockets (pulleys?) when I rebuilt my engine. I won't ever look at it again unless I rebuild it after a couple hundred thousand miles.

 

You should replace the timing chain and gears when you have the motor down for a rebuild.....................unless there is a problem.
You can't just buy a chain, it comes with new gears for the cam and crank.

 

They don't usually break, but they DO stretch to the point where they'll jump a few teeth. Especially the non roller chain sets.

 

ah ok good to know.

change the chain when it breaks or when your into your motor and its convenient to change it.

 

An easy way to tell how much slack you have in it, trans in park or nutural if standard, turn the crank pully either way about a quarter turn, then back the other way till you feel more resistance. From the stopping point to where you feel the extra resistance is the amount of slack you have in the gears and chain.

 

is this done with the plugs out...

 

Best to do this with the distributor cap off and one can observe when the rotor turns and when it doesn't.

 

Sooooo, how much movement dictates it's time for a "CHAIN" replacement?

 

It doesn't make any difference.

 

What does that mean? "It doesn't make any difference"!
How are u suppose to make the decision if it's time/needs replacement?

 

That reply was sopposed to go under MOJO's question of should the plugs be in or out.