Sorry for all the cutting and pasting. I’ve got 3B manufacture date 9/82 in Denver being rebuilt and the builder ran across an issue with the pulley attached to water pump. It has new Toyota water pump which apparently fits but the pulley taken off the original water pump doesn’t fit.
Here is his recent email
Sorry for the late reply. It was my wife's b-day yesterday, so we took it off to do other things. The new pump you sent, of which I included the part number on the box in an earlier email, matched the old pump perfectly for fitment to the block. Only after I cleaned and painted the pulley for installation did I notice that there were problems. The original pump hub (and of course, pulley) has a smaller bolt pattern for the four mounting bolts or studs, the center hub is a different diameter (1.117" on original, 1.645" on new), and although impossible to measure accurately, the depth of the hub from the engine block appears to be about 1/4" shorter (closer) on the new pump than on the original. Each one of these dimensions will affect the pulley mounting and placement of the belt groove position relative to the balancer groove used to drive the belt. Here are several more detailed pictures of the original pump for identification of what we need. A pulley to install on the new pump would be far the simplest cure for me, since the new pump is installed, but it would have to not only fit the hub, but align the pulley grooves correctly, at the same time. The hub height measures almost exactly 5 3/4" from surface to top of hub, and the bolt pattern is just about 1.420" from center of bolt to center of the adjacent bolt. The bolt holes are 8mm X 1.25" and the pulley was originally mounted with bolts.
Going to attach some pics, hopefully some other mudders can shed some light on this so we can move forward.
Thank you all!
Here is his recent email
Sorry for the late reply. It was my wife's b-day yesterday, so we took it off to do other things. The new pump you sent, of which I included the part number on the box in an earlier email, matched the old pump perfectly for fitment to the block. Only after I cleaned and painted the pulley for installation did I notice that there were problems. The original pump hub (and of course, pulley) has a smaller bolt pattern for the four mounting bolts or studs, the center hub is a different diameter (1.117" on original, 1.645" on new), and although impossible to measure accurately, the depth of the hub from the engine block appears to be about 1/4" shorter (closer) on the new pump than on the original. Each one of these dimensions will affect the pulley mounting and placement of the belt groove position relative to the balancer groove used to drive the belt. Here are several more detailed pictures of the original pump for identification of what we need. A pulley to install on the new pump would be far the simplest cure for me, since the new pump is installed, but it would have to not only fit the hub, but align the pulley grooves correctly, at the same time. The hub height measures almost exactly 5 3/4" from surface to top of hub, and the bolt pattern is just about 1.420" from center of bolt to center of the adjacent bolt. The bolt holes are 8mm X 1.25" and the pulley was originally mounted with bolts.
Going to attach some pics, hopefully some other mudders can shed some light on this so we can move forward.
Thank you all!
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