Professional Products harmonic balancer clearance...

[88 Fox GT]

I bought a Professional Products 50oz balancer off of eBay a while back and just got the chance to install it today. The reason I am using it is because I needed a 50oz balancer that would have the 3-bolts to allow me to run V-belts on my 5.0 since I will not be using any accessories other than alternator and waterpump. Anyway, I found out that to get it to clear, I had to shave off a peice on my timing chain cover just under the water pump. Well, I'm not sure what kind of timing chain cover I've got but the numbers on it say "C4OE" so I know it's from 64. The only reason I am using it is because it came off my carbed engine and already had the water pump. It looks alot different than the other timing chain cover I have that is labeled "C5OE". So different that the water pumps wont interchange.
So here is the clearance between my harmonic balancer and the timing chain cover "bump" right under the water pump.

The balancer DOES spin fine, but I am wondering if this much clearance (1mm probably) will cause any trouble in the long run.

 

[The Dan]

ATI makes a water pump specifically for this problem. Your right about the early timing cover, C4OE, compared to the C5OE. The water pumps are not interchangeable, but the water pump for a C5OE wiill work all the way through 68. The early timing cover, C4OE, saw a very small production run where the timing cover doubles as the water pump backing as well. Starting in 65 the water pump got its own back plate cover. Anywho, enough with the history lesson.

 

[88 Fox GT]

But, I should be ok right? I mean the engine spins and the balancer doesn't touch it. It's just very close.

 

[The Dan]

1mm is REAL tight, but there shouldn't be any lateral movement in your crank, so in theory you should be fine. I'd dial indicate it to check for ANY runout just to be on the safe side. No need to ruin a perfectly good balancer/engine.

 

[rbohm]

i agree, chech the balancer for run out. if you have none then you are good to go. if you have a little, and can gain more clearance by filing or grinding your pump to get it, then go for it. a smalle leak can be stopped with a dab of silicon. if oyu hav eot grind too much off the pump housing, then get a later model timing cover and a pump that will clear.