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Discussion Starter #1 (Edited)
SBC Harmonic Balancer/Damper Question

It appears my balancer is on its way out. The engine is a 74 350 2 bolt main I have rebuilt using stock pistons, edelbrock cam, edel. timing set, edel manifold & carb. When #1 is at TDC on the compression stroke I have the rotor pointing to #5 cylinder, valves are closed but the timing mark on the balancer is no where near the timing tab which is welded to the front cover. I can see the timing mark from the top (as you look down). To me the means the outer ring of the balancer, which is the stock 6 incher), is slipping on the center. Does this sound like the case? What else might it be?

The engine starts and runs with the current set up but when I try to bring it into time (8 degrees advanced without vacumm) the performance goes south.

Can I be missing something obvious?

Also, should it be the harmonic balancer, should I replace it with the stock 6 incher or increase the size and install a new timing tab? Obviously this is not a high HP set up and the truck is being built as a daily drive.
 

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It sounds like something is off for sure and when building engines its a good idea to degree the balancer in when the cam is degreed and when you check the balancer for zero mark the balancer for a 32,34,36,38 degrees so when your setting the timing you can find out what your total timing is.

On the street engines we build we use a Maroso dist. with no vacume advance and we use the light springs and most of these engines are 383 with Vortec heads and 10:5 on the compression and seems to work very well.

The timing light we us is built by Flame River and is a one wire light and does not fade out at high RPM like most timing lights do and the customers we build ther circle track engines for have these lights in the trailers and seem to work fine.
 

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When you assembled the engine were the timing marks on the cam and crank gear in line with each other, cam gear dot at the bottom of the gear and crank gear dot at the top of the gear?
If both dots were at the top of the gears the engine will start and run, but be a dud performance wise and heat up too. We found this problem on the engine in our 57 BelAir, reinstalled the gears and voila! smooth and no overheat problems ever.
 

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Discussion Starter #4
I was very careful to get the timing gear installed correctly but it appears I will have to pull the front off to make sure and solve this issue.
Thanks for the suggestions and replies.
 

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Houston54 said:
I was very careful to get the timing gear installed correctly but it appears I will have to pull the front off to make sure and solve this issue.
Thanks for the suggestions and replies.

Get the # 1 piston to top dead center + or - a few degrees, it don't have to be exact and check where the mark on the balancer is in relation to timing tab, if it's close your balancer is probably good.
Now if timing mark on balancer is to the top, you got a balancer for the cover that you have to look behind water pump to time or it has slipped on ring real bad.
 

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Houston54 said:
It appears my balancer is on its way out. The engine is a 74 350 2 bolt main I have rebuilt using stock pistons, edelbrock cam, edel. timing set, edel manifold & carb. When #1 is at TDC on the compression stroke I have the rotor pointing to #5 cylinder, valves are closed but the timing mark on the balancer is no where near the timing tab which is welded to the front cover. I can see the timing mark from the top (as you look down). To me the means the outer ring of the balancer, which is the stock 6 incher), is slipping on the center. Does this sound like the case? What else might it be?

The engine starts and runs with the current set up but when I try to bring it into time (8 degrees advanced without vacumm) the performance goes south.

Can I be missing something obvious?

Also, should it be the harmonic balancer, should I replace it with the stock 6 incher or increase the size and install a new timing tab? Obviously this is not a high HP set up and the truck is being built as a daily drive.
If you are at TDC compression firing the pointer should be pointing at #1 on the cap.
I think you got some front covers and balancers mixed.
 
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