Damper mark @ dot to dot ? ASAP

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rustytoolss

rustytoolss

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I'm building my 273. I've got the 1 piston at TDC. Cam mark at 6 o'clock/ crank mark at 12 o'clock (dot to dot) Put on timing cover and check the damper mark to )0.

((On my cover the timing marks are on the drivers side.))

Well the damper mark at TDC are 90* off., the damper mark is at the location for A PASSENGER SIDE MARK LOCATION. Whats the deal ? What am I missing . Never had this happen before.
Mind you I've just bought this truck, and it was rebuilt at sometime in the past.
 
pre 1969 the timing marks on a 273 were on the passenger side of the timing cover,,1970 and up they were on the drivers side of the timing cover,,, you have a mix match of parts,,, you either have a 1970 and newer timing cover,,thats my guess and a 1969 and older dampener,,,
 
as said in the previous post...mix match of parts.....with #1 at tdc..and slide damper on ...make new marks on damper and/or timing chain cover where they can be seen...
 
Heads not on yet and do you have a dial indicator?

If so, just remark the balancer so you can use the 70+ cover. Not hard to do.

If heads are on, get a piston tdc stop and remark the balancer.

Do a hillbilly timing tape while you are at it.

 
both #1/6 pistons are up at this point #6 on compression stroke #1 power stroke.
 
Just line up the dots on the timing chain first. The cam dot at the bottom and the crank dot at the top to get your timing chain in the proper position.

Then turn it to TDC.

Also, you will not be able to install the mechanical fuel pump in the TDC position as it will be mid stroke of the fuel pump. You must again turn the engine to a position where the fuel pump can be put in place without any "load" from the fuel pump eccentric.

Once you find TDC, if the marks do not line up between the balancer and timing cover marks, then make a mark with white paint or white out to line up with the 0° mark on the timing marks for the timing chain cover. This will get you back to where you need to be if you have mixed and matched parts for early and late small blocks (pre 69 and post 70).
 
The early timing tab is a removable sheet-metal bracket that mounts on 2 water pump bolts on the passenger's side. No reason you couldn't install one of those if you are using the early cast-iron water pump (lower hose on driver's side). That tab should match the mark on your damper. It is small, so cheap to mail and someone here probably can sell one.

As mentioned, you could also re-mark your damper for the driver's side mark on your later timing cover. I did that since I install a later aluminum water pump in my 65.

Of course, all above could be incorrect speculation since you didn't post a photo of what you have.

I also got confused about the cam timing dots. I ASSumed they should line up at TDC #1 compression, and found they aligned at TDC #6 compression. I said WTF until I read "as designed". Good I didn't try to fix the "problem" in a creative way and FU my engine.
 
I like to line up the timing marks on with the timing chain and gears loose. The cam gear mark on the bottom (6 o'clock) and the crank gear on the top (12 o'clock). Then I put them on the engine and turn either the crank or cam until they fit on the keyways, make sure that once you set the marks and gears that they don't (skip a tooth) while you install them. Then double check the marks for 6 o'clock and 12 o'clock once they are installed on the engine.

That is the way that they tell you to install the marks. Then worry about TDC.

Bill Grissom's suggestion is worth looking into, but I have a feeling that if you are using the aluminum water pump, that the old style timing mark bracket may interfere with the outlet for the lower radiator hose (I'm not positive, but it's worth checking out).

As suggested before if you can't use the old style timing mark tab, then either use white paint or timing tape to mark the new TDC location with whatever timing cover that you are using after finding TDC.
 
Let's sum this up: (I have not said anything new here)

BOTH no1 and no6 pistons come up to "the top" (TDC) at same time, and the balancer timing mark should show that if accurate

The cam turns 1/2 crank speed, so aligning the dots at 12 /6 or at 12 /12 just doesn't matter as long as you get it RIGHT and not a tooth off. Look STRAIGHT into the front of the engine, and use a straightedge

Worry about no1 or no6 firing stroke later

You SHOULD degree the cam

REGARDLESS of what parts are "mixed" you should check ACCURACY of your TDC mark anyway. Easiest method (for me) is a positive stop. With heads off, all you need is a heavy piece of strap / angle with at least one head bolt hole and a method (bolt) of stopping the piston.

With heads on, use a spark plug piston stop, which you can build or buy

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First check the balancer and make or check the original TDC mark

Figure out how to mark the balancer out to at least 55-60 degrees to take care of advance / vacuum advance This is easy. You need a good flexible tape, a small square (can be homemade) a sharp scribe, small file, and dividers

Measure around the balancer carefully and accurately. Take that figure and figure "degrees per inch"

Measure off 40 degrees. You MUST use a tape, not dividers, to make this first mark.

Now you can take dividers and divide the 40 in half which gives you your "20" mark. You can check this from the TDC mark to the 40 mark and know that it's exactly half of 40

Now take this 20 setting and make your 60 mark from 20

And......you can do the same thing with 10, etc

Use a scribe and small square to make marks in the balancer. Use a small triangular file to make the marks deeper.


It also doesn't hurt to mark the crank every 90* from TDC. This can be of help for things like setting valve lash (using the "Mopar" chart) and ESPECIALLY for doing a leakdown test
 
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