A bit of an offbeat question that I wanted to run by the experts here. Thinking through the issue, I'm inclined to think that I could not have screwed this up, but let me know if you disagree.

I have a new crate motor installed in my '81. I'm just about ready to crank it up, so I go through the procedure that I found here to find TDC, and I know that I am in the ballpark. I put the timing indicator tab on the timing chain cover the only way that it would match up with the bolt holes and not interfere with the balancer, so, i think that is on correctly. The balancer that I have has inscribed timing marks on it. I have the zeros ligned up between the tab and the balancer, and I am sure that I am not on the exhaust/intake stroke TDC on #1.

Since the balancer and timing pointer each only go on one way, I am assuming that I am good to go at #1 TDC by lining these up after making sure I am not 360* off, so my question is, has anyone ever seen these things put together with bad timing marks and/or pointers being off, or is there anything else that I am missing here?

FWIW, the pointer came with the engine (GMPP) and the balancer is a Summit brand, mid-level (not the cheapest) job.

With all of the timing threads out there, this may have been covered before, but the question is obscure enough that finding the answer would have been quite difficult if it were. Thanks.

 

I've seen the timing marks and tabs WAY off on many occasions. I always verify and correct the marks with any new engine.
Lars

 

......and on some model small blocks, the timing mark on the balancer is NOT aligned with the keyway and the timing cover tab is indexed for it....i dont remember which years or models ..i think around 77-82?

 

Thanks Lars. I'll reverify with the method that I found on here (pasted below). It sounds fairly easy unless there is something that I'm missing about what Motorhead was describing.

Rotate the motor until you see the exhaust valve on the #6 cylinder closing and the intake opening. When they are equal ( you can look at the rocker arms, go back and forth until they look the same ) you are in overlap on the #6 cylinder and you will be at TDC on #1 cylinder.

 

I found that when I replaced the Ignition on my 1979 the balancer had slipped and was about 22 degrees advance TDC. I got a new balancer, replaced it with a good one. I compared the old and new. I also looked at the key way relationship with TDC. The key way on my 1979 was approximately 4 degrees retarded.

 

To verify the TDC timing mark u need a degree wheel and a piston stop. If u want the full procedure just ask. First remove the spark plugs then install a piston stop. It then involves rotating the engine each way to the piston stop and settineg the degree wheel to zero at the mid point. Verify it at least twice. Thats your TDC so set your timing tab and balancer to match.

Hardest part is to find a good piston stop. Most are junk and are easily bent by the piston no matter how careful u are. I now make my own piston stops from used spark plugs. Knock out the insulator and thread the hole for a common stove bolt (electrodes removed of course). Use a nut to lock it down.

Good luck,
cardo0

 

That's not accurate enough. You need a piston stop. I have a complete paper on how to do this without a degree wheel. E-mail me for a copy of the instructions:
V8FastCars@msn.com
Lars

 

You have mail. Thanks again.

 

As a follow up, I did the piston stop method, and it looks like the marks were off just a hair. TDC appears to line up with the 2* mark on the balancer, but the difference could be attributable to the lack of precision in my execution, but I think I got it as consistent as I could. In any case, I will be very close.

 

With early balancers, the TDC mark aligns with the keyway; on later balancers (~1969), the TDC mark is 10 degrees counterclockwise from the keyway.

 

As long as the TDC [you identified] is during the correct engine cylce (immediately following intake valve close), you should be fine. A couple of degrees off for a street engine is not a critical issue unless part clearances are extremely close.

 

I had the valve covers off the first time I went through just to line up the marks, so I know that I am on the right stroke. I'll have to yank them off again before I install the distributor though since I'll be turning the engine over while priming the oil pump.

I'm getting really close to being able to start this puppy up, provided all my wiring went together correctly.