I have a 69' 350 putting back together to sell. I took it apart to do a cam swap, rotating assembly stayed in. Now trying to put balancer back on, but there are no threads period in my crank. I have the right balancer, put a little grease on it and it slid right in, but it seems to wobble and can easily come off. Also I know I am hitting the crank gear, but it seems like the balancer is only half on??? I have different balancers, but they are for different engines. Anybody have any experience with this?

The early 283's and 327's were the same way. No crank bolt, and these fancy harmonic balancer installers ,,, well there is a reason old timers still have a 2x4 and a BFH laying around the shop ;) You can heat the balancer in hot water and then DRIVE it on. But your mention of 'pushing it on by hand',, that's not going to do the trick. Something is wrong. You have to have a 0.0005" interference fit for the balancer to have any effect, and simply for it to stay on!

Like Marv said, most early SBC did not have threaded crank snouts, but those balancers were pressed on at the factory. Using a block of wood and a BFH was an accepted method but led to other issues too.

By the time Chevy got around to 350's, crank snouts were threaded. If the threads have been stripped out, they can be re-tapped and there are several options available, this was just discussed a couple weeks ago. If you can't get it figured out, post back up and we'll be glad to help.

BTW, make sure it's a 350 first...

What would happen if I put a different 350 balancer on this engine?? This one seems too loose. I have another one that is tighter. I did blast this one in my cabinet (loose one) for re-painting, but I tried to stay away from the center portion of the balancer. It is still smooth on the inside I don't think this is the problem. Could it be the key? I don't know what to do at this point I am positive this is the balancer that came off this engine, now it seem to loose.........:(

OK I'm confused. I posted a balancer installation question a few weeks back and was told by everyone...DO NOT hammer it on as it can destroy things in the engine, like the thrust bearing, etc...

Here: http://www.nastyz28.com/forum/showthread.php?t=87704

I've hammered many of them on over the years, no other way to do it under the shade tree here. Hammered a few of them off too. In this case I'd drill and tap the crank end and put a bolt in it. The crank is pretty soft iron and is easy to work with.

How about drilling and tapping the end of the crank so that it could be installed like the later 350's? Just a thought............................

Drill and tap it for a 7/16" find thread. Then "pull" the balancer on with a longer bolt then install a harmonic balancer bolt to make sure stays put.

Before I had the knowledge and/or tools to drill and tap the crank, I used a bottle jack and a long 4X4 post between two posts in the garage to press a harmoic balancer on. PITA to do but you do what you have to do to invent and build the wheel.

I have NEVER hammered a harmonic balancer on. It creates a dangerous situation by possibly separating the outer ring from the rubber bond between it and the center hub. When the outer ring comes off (usually when the engine is at peak rpms) say goodby to anything in its path.

Shawn,
The BFH routine is a method of last resort. I surely wasn't advocating it as 'acceptable' unless you have no choice. There are a lot of ills to the hamer method, including destroying the bond between the initera ring and the hub of the balancer like Cardinal said, destroying the thrust flange at the rear of the crank, distorting the rear main bearing, many a many of cranks were cracked when some over zellous 'armstrong' shop labor hammered the crap out of the balancer as it seated on the timing gear. But,, I'd bet between 1955 and the early 70's a couple of hundred million balancers were hammered on and no one ever knew the difference. DON'T DO IT, it's not worth the risk these days. All I'm saying is before we knew any better,, it was done all the time and motors survived. (or at least the damage was blamed on some other problem ;) )

The BFH should only be used for delicate jobs...............like glass removal!!!!
;)