Hi Guys, I'm trying to put a new pump on my 54 Mercury Monterey coupe (256 Y Block). The pumps I order seem to be the correct shape but way too big. The old pump had a 4 in impeller, and the replacements look like a scaled up version with 4.5in impellers, so they won't fit. Am I missing something?
These guys would surely know. You might even find an answer there by searching. http://forums.y-blocksforever.com/
sure, they changed the size of the pump some time in the mid 50s. Early ones are small, later ones are larger. Where are you ordering the pump from? What info are you giving them about the car/engine it is supposed to fit?
Original pump is in pieces, previous owner tried to push the bearings and it didn't end well. I put in 54 Monterey for a couple places (O Reilly, NAPA, etc.) they all come back with the same pump that's too big. I wonder if I can change the timing cover to fit the bigger pump, would that cover bolt up to the block?
The cover should bolt to the block, but there might be other differences...also truck and car and T bird covers have some differences, so be careful shopping. If you do a search either on the hamb or on google, you'll find lots of discussion about how hard it is to find the correct water pump, and how many different varieties there are.
Rock auto shows the same pump from 54 to 62. but try auto parts warehouse they list a different pump for 1954. There is one on Ebay that list a 4" impeller but it's pricey
Going outside the box : Any thoughts about finding a way to turn down the new impeller to 4"? Although replacing the timing cover is also doable, & would give you a chance to inspect the timing chain & gears.
Look up a pump for a 1954 Ford with a 239 OHV. They were a one year only smaller pump. Your 256 Merc will be the same pump
The Jalopy Journal
