I have seen it mentioned on other posts that 35 year old harmonic balancers can slip or rotate which throws off static timing. To understand if this condition exists, is there a way of checking the timing mark relative to the crank key way?
Where should it be?
Are they suppose to be in direct alignment? or offset?
If they are offset, by how much?

The reason I am asking is that I can't make my SL6 ping no matter how far I crank up the timing. I have a little over 10,000 on a new rebuild. The distributor is a clean rebuild from NAPA. The govenor is a 10R and the vacuum advance is a 11R. I am running it at 16 degrees initial.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

The best way is to bring #1 cylinder up to TDC using a Dail Indicator so that you get it truely at TDC. And then see where the mark falls.

It dont sound to me like it is out though. But even ones that have not slipped can be off some, so its a good thing to do this just so you do know exactly where your timing is.

Sounds to me like you have built a very good combo. Sometimes you just get things right. When you do they are very resistant to pinging & such. I bet it runs good no matter where you set the timing (within reason). A engine that has a combutio0n chamber that works very good will not loose as much power from having the timing off, compaired to some engines that want run worth a crap unless you have the timing within a very small window.

Also if the HB ring slips bad enough you can get a lot of vibration. But it would not hurt to check it the way I described just for a piece of mind & knowing exactly where your timing is.


It is possible that the machanical advance is not working like it should & your not getting the timing that you think you are. A timing tape & a good timing light can anwser this question. Also not having the timing vacume advance hooked to the right port can cause it not to get the right timing.

But with the MPG you quoted in your sig, and if it has good performance, my guess would be that it is doing fine. But still a good thing to check. Even when they are doing good, it may be possible for it to do better.



Jess

Everything is new. I took the distributor apart and it all looks good and the weights move freely. 10R govenor and 11R vacuum advance.

Do you have a picture of a harmonic balancer showing the crank key and where the timing mark is in relation to it?

Thanks,

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Happen to have an NOS balancer, and I never really looked at it closely until now. The part number on the box is 4095527, and the number stamped on the balancer is 85985 2283. With the keyway at 6 o'clock there is a timing mark at 2, 6, and 10 o'clock. The only mark that goes completely across the v-belt groove is at 6 o'clock, in line with the keyway. Wassup? Is this a generic one size fits all replacement or what? Have pics and would gladly post them but I haven't figured out how to do that yet. Hope this helps.

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If a MedAlert bracelet is the only bling you wear......You might be getting old.

Hope this works.

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If a MedAlert bracelet is the only bling you wear......You might be getting old.

It looks like the timing mark is in align with the crank key, since you said the 6:00 position is the only one going across both sides of the pulley.

I appreciate you posting the picture.

That really helps, thank you very much!

It is one of those details that I hadn't thought about much and took for granted too!

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

That pic is at an angle so its a bit hard to judge...

Please remember this offset is dependent on which timing cover (different timing mark tab location) is being used.

When DamperDudes built mine they built in a 5deg offset as they said that is what is right for me (1971 cover, 3 spoke dampner). I'm with Jess on this one, find true TDC and see. Once my piston stop comes I'll find out.