Putting on a b&m 250 supercharger on a 502 merc thermostat problem.
 

Ok so I have looked around on threads and google but I can't find the right part I need to keep everything stock for water circulation on 502 and a B&M 250 blower. I would like the exact part i would need to keep all 4 hoses connected and retain everything like it is now. please help me out with what i need to get this blower up and going.

Ok I got a hold of CPperformance and got the exact bypass I need. If your running a fresh water cooling system and not a closed cooling system there is no need for the water pump on the front of the motor. So the only thing that is needed is part number 520-250bmkw kit and it will hook everything up to b&m supercharger keep your cooling with or without a thermostat and gain a couple of horse by not having to turn the water pump. I know some people out there were wondering what to do and no one had the correct info. so hopefully this will help someone out.

fixx
 

ok if you say so...why do the 525 sc and 600 sc run a circulation pump??

all toy really had to do was use the hoses going to the lower part of the exhaust manifolds and plug the 2 on top,then use the 2 port thermostat housing that came with the blower set up..

I run recirc. pumps and with my B&M 250's. B&M made a thermostat housing extension that mounted to the intake manifold and curved to the side if the snout of the blower, and then you mounted the merc thermost housing to it. From what I have seen they are hard to come by, but they should be out there. I have been running this set up for 8 years, and I am really happy with it. I boat in Michigan's colder water and my engines always have engine temp, so I do not get the condensation build up like a lot of blower motors get with cold water / engine temps.
Hope this helps. I just wanted to let you know of optins you have with the 250's.

sweet all i posted was what I was told by cpperformance, I appreciate the other ideas if you run across the b&m part that i can run my stock setup i would be good with that, but i just dont know what that part looks like, so im not buying a bunch of stuff that may work or not.

Is this the part you were talking about? http://www.holley.com/90845.asp
If so, when I put the stock thermostat housing on that will all the hoses reach or will i need to do something with all the hoses like buy new ones or extend some of them?

fixx
 

this is what you need,,its made for your blower,put rubber caps with a hose clamp on the hoses that got to the risers and get some 1'' hose i think lol and from this thermostat housing to the lower paer of your exhaust manifold..

http://www.hardin-marine.com/p-12556...th-bypass.aspx

also order their 140* high flow with bypass thermostat and you will be good to go..also make sure you put big jets in and work your way down from their...you also want to put your fuel pressure at 7 psi and make sure your fuel pump is a MINIMUM 135 GALLONS PER HOUR..

you may want to order a 120 thermostat also just in case your oil gets too hot,,you may notive low oil pressure after a run,if so run a 120* stat..
http://www.hardin-marine.com/search....erm=thermostat

oops chit i forgot,,where is the hose going to go for the circulation pump,,duh me...with what i posted you will need a cross over...


sorry!!

Yeah that is what that whole kit it from cppeformance it has that piece and the crossover plus thermostat. I'm wondering if that Holley thermostat part would work to move the OEM thermostat housing to the right and just plumb the hoses over to the OEM housing. The only issue I see is the OEM thermostat housing will be up and down instead of front to back