Harmonic balancer difference?

Catchb52

New member
I am fixing a 1973 1310 that had a 304 in it. The engine broke a rod. We found a 1968 266 that was in good shape but missing parts. So far I have been able to use the 304 for the missing part

The 266 is missing the pulley off the harmonic balancer on the crank. I found that the balancer and pulley on the 304 has more weight on the balancer than the 266. Can I use the 304 on the 266?

Also had to use the distributor from the 304. Fits, but it is not pointing at #8 even when turned 180 degrees. Was there a difference between distributors for the 266 and the 304?
 
I can't give you a definitive answer about the balancer. What I can say is these engines were externally balanced, so ring gears and balancers factor into that equation. Swapping those parts around between engines has been known to create vibration issues at certain rpm ranges. Not saying it necessarily would in your case. There's really no way to know without trying.
IH used different brands and models of distributors in the SV8 engines over the years, but the fitment was the same, no matter if it was a Delco, a Holley curved points, a Holley straight points, or a Prestolite etc. What fits in a 266 will fit in a 392 vicey-versy and all sizes in betwixt. The weighted mechanical advance curves differed somewhat between the engine sizes. GVWR also played a role in that setting. Those curves can be adjusted though by changing spring weights.
 
The other part of your question about #8 plug wire location has me thinking that maybe you aren't ensuring that the #8 piston is at the top of the COMPRESSION stroke. It will be at the top on the exhaust stroke also, but setting your timing to that stroke will place you 180 degrees out. If you ensure that #8 piston is at TDC COMPRESSION before you stab the distributor, then it doesn't matter which distributor cap location happens to be above the rotor. That is where your #8 plug wire goes. It can be any of the eight spots, just as long as it's the RIGHT spot.
 
Thanks. That was my understanding. I can just move the wires one wire over and #8 will be correct. I did check that it is on TDC compression.

Cap has a #1 and that is what threw me off.

I had the flywheel and clutch balanced, but just noted that the weight on the harmonic balancer is thicker and not cut out like the 266.

The 1310 is a High rail vehicle (runs on the railroad track and on the road). It is primarily used on the track, so not a lot of RPM or torque used.

Still a bit concerned on the balance. May check with IH Parts to see if they have the pulley that goes on the 266 balancer.
 
Back
Top