timing mark

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It's allready marked.

There are 4 lines in it. When you put it on the crank and, spin the engine around until the piston is at TDC on the fire stroke. That'll be the line.
 
Get yourself a spark plug and knock out the electrode. Jam a 2" long bolt in there and cinch it down so it cant come out. Get the #1 cylinder started on the compression stroke and put it in the #1 cylinder.Rotate your motor by hand until the piston touches the stop, er..bolt. Mark the damper and then rotate it backwards until the damper hits the stop again, mark it and then bisect the 2 lines on the damper. Thats your TDC, or as close as the stretch on your chain allows...
 
, or as close as the stretch on your chain allows...


The stretch of the chain has nothing to do with it. This method is as accurate as you'll get in practical terms. I ALWAYS check an unknown engine in this way, because f the possibility that the damper can move with the rubber insert

pic_installation.jpg
 
....The stretch of the chain has nothing to do with it....

My bad, you are absolutely right. I was thinking cam timing. If you got mass amounts of slop in your chain, the crank can move 2-3 degrees before the chain tightens up on the backstroke. Thats why you move the crank in the operating direction and if you over shoot the mark, you back it past the correction a few degrees and run up to the mark again in the operating direction. If you have a chain tensioner or a single idler gear, this isnt necessasy, but a sloppy chain will fool you if you just backpedal to correct and leave it at that. This applies to distributor timing and cam timing.
 
Get yourself a spark plug and knock out the electrode. Jam a 2" long bolt in there and cinch it down so it cant come out. Get the #1 cylinder started on the compression stroke and put it in the #1 cylinder.Rotate your motor by hand until the piston touches the stop, er..bolt. Mark the damper and then rotate it backwards until the damper hits the stop again, mark it and then [bisect the 2 lines on the damper]. Thats your TDC

correct.:read2:
 
My bad, you are absolutely right. I was thinking cam timing. If you got mass amounts of slop in your chain, the crank can move 2-3 degrees before the chain tightens up on the backstroke. Thats why you move the crank in the operating direction and if you over shoot the mark, you back it past the correction a few degrees and run up to the mark again in the operating direction. If you have a chain tensioner or a single idler gear, this isnt necessasy, but a sloppy chain will fool you if you just backpedal to correct and leave it at that. This applies to distributor timing and cam timing.

For the more exacting approach :toothy10:
 
OK this explains how to find the TDC when the motor has some miles on it.... would this be necessary on a new build with a fresh chain?
or could you just run it up on the c stroke until the piston stops moving up.....I seem to remember using a longer thin screwdriver and watch it move up and up then it would just stop moving and the mark would be on zero or really close to it..... seem reasonable?







Get yourself a spark plug and knock out the electrode. Jam a 2" long bolt in there and cinch it down so it cant come out. Get the #1 cylinder started on the compression stroke and put it in the #1 cylinder.Rotate your motor by hand until the piston touches the stop, er..bolt. Mark the damper and then rotate it backwards until the damper hits the stop again, mark it and then bisect the 2 lines on the damper. Thats your TDC, or as close as the stretch on your chain allows...
 
OK this explains how to find the TDC when the motor has some miles on it.... would this be necessary on a new build with a fresh chain?
or could you just run it up on the c stroke until the piston stops moving up.....I seem to remember using a longer thin screwdriver and watch it move up and up then it would just stop moving and the mark would be on zero or really close to it..... seem reasonable?

This has NOTHING to do with the timing chain, and you can NOT find true TDC with a screwdriver.

There has been some other methods, such as rigging up some sort of dial indicator, or using a balloon partly filled with air/ water/ oil/ "depending" on what you read

The fact is, here-----balancers can "move" because they have an outer ring molded in rubber to the central hub. ANY engine using a rubber based balancer is subject to this movement and should be checked occasionally, CERTAINLY when it's a "new build."

The problem with trying to use a screwdriver--or anything else, is that the piston SLOWS DOWN dramatically the last few degrees of travel.

EVEN if you are checking with the heads off and using an indicator, you NEVER "shoot" for TDC. You use the same method as outlined for the piston stop, I.E. you bring the piston up CW until you get "some reading" BEFORE the piston comes all the way up. You mark the wheel. Then you CONTINUE CW in the same direction, until the piston comes "up and over" and shoot for the SAME reading you had the first time, and mark the wheel again. Just like using the piston stop, you now have two marks.

Of course you can ALSO use a piston stop with the heads off. Just take a scrap of angle iron, etc, drill it for two head bolts, and tap or "jam nut" a bolt above the piston.


Back in "my day" I used to tune up cars on the Naval Station. I found a LOT of seemed like -'specially 352/390 Fords back in that era--on which the dampener had moved.
 
My fluidampr doesnt move.I can put the damper on 0 and the piston is tdc. One of the plus,s of a quality damper.
 
My fluidampr doesnt move.I can put the damper on 0 and the piston is tdc. One of the plus,s of a quality damper.

the key way can be off is the problem, you must have lucked out.
the factory cut the key ways slightly off most of the time.

mine seems to line up as well, but if you really check it and find true tdc...it's off almost 5*
 
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