Back in 2012 sometime we were talking about new water pumps and Charles said this;
MSeriesRebuild wrote:All these vendors use the same source of supply that we do for these pumps. S&S Truck Parts. They are not a direct cross over, the shaft hub is shorter, but they are good pumps, however the spacer will need to be machined so it is thin enough to compensate for the shorter hub length. Otherwise the fan has nothing to center off of. We have never had a issue with one.
Does anyone know if this issue has been corrected on newer pumps.....or is the shaft hub still a bit short? I haven't seen anyone selling the pumps mention this, so I'm curious. I didn't want to PM Charles as I know he's a busy guy and will answer when he can.
I see new ones listed on eBay from ablinn and no mention is made of having to machine a spacer. I'd like to know as well, I was planning on holding off on replacing mine because I have a 4BT all set ready to go in, but time isn't on my side recently and I'm not sure I want to sideline my truck during prime driving season for the swap process.
Last edited by Tuko on Sat Mar 14, 2015 5:24 pm, edited 1 time in total.
I purchased one of the new water pumps from John after issues with rebuilt pumps available locally. Mine was to fit the 251 in the M37CDN and it was an exact replacement. It is the same as the one for the 230. Its working fine, unless I am missing something.... Maybe Charles could give you a better explanation if asked.
So when you installed the new pump (with the spacer behind the fan) the shaft was long enough to stick thru the center hole of the fan and center it? That's the crux of the issue.
The largest rebuilder of classic & rare water pumps in the US is just down the road from me. They even have an on-site foundry for parts unavailable anywhere else.
So when you installed the new pump (with the spacer behind the fan) the shaft was long enough to stick thru the center hole of the fan and center it? That's the crux of the issue.
thanks,
bob
I had to go up to the shop and look to be sure. My new pump installed with pulley, fan with spacer, lines up perfectly with the crank pulley and the centre extends beyond the fan over 3/8ths of an inch. Keep in mind this is on a 251, in case there is a difference but its the same pump as the 230. I got a rebuild before this one and after sitting for a month, the seal leaked like a sieve. Unfortunately I had it on the shelf for a year so did not get to exchange it. Hope this helps.
I know this is digging up old stuff but same issue. Does anyone have a correct water pump for the M37? All these new ones have a short hub and does not go all the way thru the spacer. I just can’t see putting the fan on without centering it. On top of that these new hubs are smaller than the hole in the spacer.
Anybody have any NOS ones laying around?
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