69 435 water pump pulley numbers

[Mark A.]

Hi,
My 69 435hp engine has a #3890419 CT water pump pulley. It is a 2 groove pulley.I would like to know if this is correct for my car. It is a non power steering car. Thanks for the help. Mark
P.S. If someone could direct me to the correct book that has these numbers, I would appreciate it. My judging manual does not.

[Grant W.]

Re: 69 435 water pump pulley numbers

Hi Mark
From my parts book I have part number 3995644 I think that was also on my 69 435hp car when I had it. Anything else??? Thanks, Grant

[Grant W.]

Re: 69 435 water pump pulley numbers

Just to add. It is a 3 groove pulley. The one you have is incorrect. Thanks, Grant

[Mark A.]

Re: 69 435 water pump pulley numbers

Grant,
Thanks for the help. Would my car use a 3 groove pulley even without power steering? As it is now I am only using 1 groove because the A.I.R is not hooked up. Any idea where I might find the correct pulley? Thanks, Mark

[Grant W.]

Re: 69 435 water pump pulley numbers

Hi Mark
My car did not have PS either and it used the 3 groove. The AIR belt would go on one of the grooves. You can also use a 3889372BF pulley if you have a very late 69. In the book the 3889372BF pulley indicates its for a 70 but I had 70's 219 heads on my car and heads were dated Sept 69,
The 3995644BF pulley is really hard to find. The reason is it also fits the 67 tri power cars and they get snapped up really quick. I've seen them sell anywhere from 300.00 to 400.00 The reason is the S stamping and the part number is stamped on the pulley.
You can buy a repop non stamped pulley for about 88.00 from Corvette Central. However I would rather find the real deal because if you were to get the car judged I've seen them use the little mirror to see what is there. Just my 2 cents worth.
I probably know who has a bunch but they are "not for sale" If you are really in a jam I'll see what I have in my garage but I can't promise anything.
Thanks, Grant

[Joe L.]

Re: 69 435 water pump pulley numbers

Grant,
Thanks for the help. Would my car use a 3 groove pulley even without power steering? As it is now I am only using 1 groove because the A.I.R is not hooked up. Any idea where I might find the correct pulley? Thanks, Mark

Mark-----

The original pulley was GM #3889372, a 3 groove pulley of 5-1/2" OD. The GM #3995644 that Grant mentions is a 1971 replacement for the 3889372. It's 100% functional, but it's not the correct pulley for a 1969 L-71.

The 3890419 was a pulley used for some small block applications from 1966 to 1970. However, it or GM #3848904 can be used in conjunction with a 3883235 1 groove pulley for 68-69 big blocks. In fact, the 3848904 + 3883235 was used for 68-69 L-88. The larger OD of 3848904 slowed down the fan speed for the higher RPM L-88. In any event, while it can be used for non-L88 applications it's not what was originally used.

It makes no difference whether the car has power steering or not as far as the big block waterpump pulley is concerned. The power steering pump on all Corvette big blocks is driven from the alternator pulley, not the crank or waterpump pulley.

ALL 1968-69 Corvette big blocks require 3 grooves on the waterpump pulley. Usually, this is accomplished by the 3889372. In the case of L-88, it's accomplished by the 2 groove 3848904 + 1 groove 3883235. The inner groove is always a captive belt between waterpump and crank (except C-60); the center groove is the alternator drive; the outer groove is the AIR drive.