what is the bolt size for the 350 water pump pulley? To be clear, the bolts that hold the pulley on the water pump. Thanks.
It is studs and nuts, not a bolt. Pretty sure the studs are 5/16 coarse on one end and 5/16 fine thread on the other. I always forget which end goes into the water pump and which end the nuts go on. I believe the nuts are the fine thread. I am sure someone will correct me if I a have that reversed.
It’s a clutch fan but the studs are long gone. Had bolts on it when I got it now can’t find them after I replaced the water pump
The studs are the same as the Holley short carburetor studs. These are 1.5" long, pretty sure these will work, https://www.holley.com/products/fuel_systems/carburetor_components/carburetor_studs/parts/60 See the coarse and fine threads?
I'm sure you can purchase the proper studs at NAPA or other auto parts store. Studs make installation a lot easier. I think Larry is spot on with the size.