Looking to replace the water pumps on my 51 Merc Flathead. There are many aftermarket pumps available, some offering different styles of bearings to replace the OEM bronze bushings and carbon seals. They are also offered with a better impeller design. I am not looking to rebuild the old ones. I have seen them available from Flathead Jacks, Dennis Carpenter, Speedway, Bob Drake, Hot Rod Supply,just to name a few. Are they all different, or are they the same just relabeled? Please let me hear of your experiences both good and bad. Thanks.
I don't think drake currently offers late flathead pumps, at least... they didn't when I needed some pickup ones last year. I used the sped-way ones and have been very satisfied with them so far (5k mi).
I have used Speedway pumps on three different engine...pre-48...no problems. Actually they worked beter than I expected. All these "new design" pumps are better than the stock units. Far better.
I also have a pair of Speedway pumps on my 52 flatty for a couple of years now with no problems and great results as to cooling the thing down.
The big difference is that his still has the bushings, whereas Drake and Speedway went to rolling element bearings. That change should make the pumps less sensitive to increased belt tension. Bob
Bought two Speedway pumps almost 2 years ago. FINALLY got around to putting the flattie back together and painted up the pumps really purty for install. The driver's side installed fine. Put the passenger side on, and CRACK! The casting broke at a freakin' bolt hole (and, no, I wasn't crankin' on it hard...). Called Speedway. Since it'd been way over a year, they wouldn't make it good --sigh-- (yeah, I know, it had been a long time...). After a long conversation with a supervisor, it was decided they'd sell me a new one at 1/2 price. Not sure if I just got one of the early castings and they sucked, or what. Haven't heard many folks have trouble with 'em, though. Well, besides me, anyway...
I have been running Speedway pumps on my AV8 for over 6 years and about 40,000 miles. When I first installed them, I had to grind some of the pump body to clear the timing cover. It interfered by about 1/32 inch. Also, is there any value in a pair of '49 merc pump cores? P/N OCM 8503/4 These look like the 8RT truck pumps, but the mounting "ear" is higher on the pump body and they have the narrow pulley.
I run speedway pumps on both my flatheads, all them bolted right up with no problems. Cool fine, don't leak, priced right.
I will say this... if you need the early pumps, the Drake ones seem to be of higher quality that any others I've seen.
I've been running the Speedway truck pumps on my 40 Ford coupe for about 6 years now, around 40K miles I would say - no issues.
Go on the Ford Barn and pm a guy named GM, he has a contact for water pumps that he is all into, he will probably tell you more than you ever wanted to know.