Wrong balancer?


I'm trying to put a new 8" harmonic balancer onto a Goodwrench 350 engine. I bought a balancer cover with the timing marks on it. The problem is the timing marks on the balancer vs the cover aren't even close. Looking from the ront and with the keyways in the 12:00 position, the TDC groove in the balancer is at approximately 10:30 position and the TDC mark on the cover is approximately 11:58 position. I wonder if its the wrong balancer?

John DiMartino

PlowSite.com Veteran
Somewher in the late 70's GM changed the location of the timing marks on small blocks,the newer ones had then around 12 0'clock and you timed then=m by sticking the light down behind the water pump.I think you have an old style balancer on a newer engine,it wont harm anything,other than not being able to time it to manufacturers specs,you'll have to powertime it.I think they changed the location when they started adding lots of accesorys like AIR pumps,a/c powersteering,during the 70'sThe extra belts made timing it from the side impossible.


The timing tab on the old engine is located just right of center and I have to aim the timing light down on the waterpump to see the marks. I think the balancer and pulley are from a '75 350, but I'm not sure. I ordered another balancer today for a '75 350 instead of an '83 to see if it aligns right. I'd like to put the aftermarket cover on it so there is no shift in timing marks way out in the future. Another thing, what should I torque the harmonic balancer bolt to when I install it? That is critical on some engines.
Get an aftermarket timimg pointer (much stronger) which bolts to the block beside the timing cover.You can use any balancer,as long as they are the same diameter,and NOT for a 400.Jjust remark it with TRUE top dead centre.The factory marks are usually 2-4 degress off anyways.

Here's how you do it- install the new timing pointer (or you can use the original one if you wish),and the balancer on the engine.Take an old spark plug,and hammer out the centre electode.Run a 3/8 course tap through the centre,and install a long 3/8 bolt into it.Bring the engine close to TDC and install the modified spark plug.Screw down the bolt until it touches the piston.Make a temporary mark (liquid paper works well) on the balancer.Now,Slowly turn the engine backwards with HAND TOOLS ONLY,until the piston contacts the bolt again,and make a second mark.Halfway between these marks is TRUE TDC.Repeat the process just to make sure you were accurate.This will allow you to use any pointer and any balancer and not have to worry about marks lining up.When you are sure you have found it use a fine hacksaw blade to cut a small groove in the balancer and fill it with a bright colored paint.