1962 "609" Water Pump

[Christopher R.]

Does this water pump have slotted screw heads or hex headed bolts holding on the rear cover?

[Joe L.]

Re: 1962 "609" Water Pump

chris-----

I believe that 62 was still using the slotted screws. If the backing plate is flat, then it definitely had the slotted screws. I don't think that any pumps were ever made with the flat backing plate and hex head screws.

[Mike E.]

Re: 1962 "609" Water Pump

Joe, I have to disgree with you. I've seen 20+ original 609 pumps on 62's over the years--all had hex head screws holding the rear plate on.

[Joe L.]

Re: 1962 "609" Water Pump

Mike-----

Did they have "flat" backing plates or those with "turned up" (reinforced) perimeter?

[Mike E.]

Re: 1962 "609" Water Pump

Turned up.

[John D.]

Re: 1962 "609" Water Pump

Chris, My knowledge is limited on the 609 pumps but I can tell you this since I own two of them. One has the flat backing plate and has slotted screws. THe other one which is on my car had the hex head bolts. Don't know which backing plate it has though. I have seen both styles on 609 pumps. Think the earlier ones had the slotted screws and the later had the hex plug. Check the date on the pump. Look inside the water passage way when you are rebuilding the pump and your might see a casting date.
Rev. Mike though is a 62 man for sure. I would stick to what he says on the pumps. Big thing to remember is if you use the later style backing plate it will probably smack up against the timing gear cover and cause you grief for sure. John

[Joe L.]

Re: 1962 "609" Water Pump

Mike-----

OK, I thought that the flat "plates" were used into the beginning of C2 era cars. As I mentioned, I've never seen a pump that appeared at all to be as originally configured with a flat plate and anything other than slotted screws.

However, I think that most, if not all, of those with the "turned up" perimeter reinforcement used the hex head screws. I thought that, if there was any situation in which the slotted screws were used with the "turned up" plates, it would be the 61-63 period. Looks like that's not the case.

The strange thing is that Tonawanda and Flint must have used different style screws at the same time. Early big blocks waterpumps, first used of course in 1965, have the slotted style screws. I don't know if Tonawanda small block pumps of the same period used the slotted screws, or not, though.

By the way, the "flat" plates used for earlier small block waterpumps do not really seal very well. I've tested some of these and they'll barely hold 15 psi.

The later "turned up" perimeter plates with the raised center section seal much better. However, their fitment is "touch-and-go" for many small blocks with short leg pumps. And, if one tries to use extra pump-to-block gaskets to increase clearance between the pump plate and the timing cover, then one ends up with pulley alignemnt problems.