oldguy668
04-18-2015, 11:34 AM
I am using a Gilmer drive system for my 289, switching from a serpentine system which was totally out of character for an old school look. Initially, I used the late reverse rotation (CCW) pump to mock up the Gilmer system. Got all my spacers set up and set up the length on the tension arm under the alternator. When the standard rotation (CW) pump arrived, I discovered something I have never seen mentioned in any of the discussions about water pumps.
The CW pump's pulley mounting face is about 3/8" to 1/2" closer to the block than the CCW pump. and the shaft centerline of the CW pump is about 3/4" closer to the passenger side of the engine. Neither issue is causing me a problem, but I thought this particular observation might be helpful to someone else.
Both pumps were mounted to the old (1968) timing cover and I'm wondering if using the later timing cover with the CCW pump corrects for the difference in the pump body.
The CW pump's pulley mounting face is about 3/8" to 1/2" closer to the block than the CCW pump. and the shaft centerline of the CW pump is about 3/4" closer to the passenger side of the engine. Neither issue is causing me a problem, but I thought this particular observation might be helpful to someone else.
Both pumps were mounted to the old (1968) timing cover and I'm wondering if using the later timing cover with the CCW pump corrects for the difference in the pump body.