500 efi seawater pump
 

Hi,
I am converting to a 500efi from a late model 502 mpi serpentine system.
I have everything except the sea water pump.
I kind of looks like I can use this the sea water pump off of the 502, it lines up but off just a little front to back. I was thinking of putting some spacers where the pump mounts to the bracket to solve the problem. Now I have someone that may need the pump because they want to buy my old blower setup and need to convert to serpentine system.

So here is my question. I am running a 565 around 1000hp. I figured the stock bravo, non-fuel pump, seawater pump would be adequate to feed the engine. I have a separate feed for the inter-cooler off of a separate Hull pickup and strainer.

So if I need a different pump, I was thinking the older 500efi pump (non-fuel pump version), or something after market.

So is my assumption that the single stock sea water pump is adequate for my needs?
If yes, does anyone have an older efi 500 seawater pump with bracket, pulley, etc, or know where I can get one?

Or is there a reasonably priced after market pump that would work with bracket, pulley, etc?

Thx
Larry

must be a tough question!

What do u use for a seawater pump?
There are probably a lot of 850hp plus motors out there?

I don't think the waterpump will be an issue so long as the impeller & housing are in good shape, the bottleneck is the thru transom fitting. If you have an aftermarket thru hull pickup the issue would be too much pressure, in that case you will need a relief valve plumbed in to dump excess water pressure. Randy

pressure
 

Why would too much pressure to the pump be an issue?
I also need to find a complete older style 500 efi pump with brackets and pulley, or a suitable aftermarket unit.
Thx
Larry

Not too much pressure to the pump, but to the engine. It can cause gasket failure. My 650s have dump valves set to about 14psi on the output side of the waterpumps. Supposed to prevent pressure spikes from jumping wakes or waves when you re enter the water. The engine builder said he wouldn't honor any warranty claims related to cooling without them. Cheap insurance but probably not an issue with stock power otherwise merc would install them from the factory. There are waterpump set ups for sale all the time in the swap shop. Randy

correct, bur i need the specific braket and pulley to match up with the rest of my 500efi serpentine setup.
i have been looking for 3 months and haven't found one yet

Larry my motors were 2000 500 efis, no fuel pump on the sea water pump, they are now 509s with whipples, I how I plumbed the pumps were from a transom pickup, to the sea strainer with a pressure relief valve, than to the pump, the intercoolers I plumbed from the pick up from the drives, to a strainer than to the intercoolers no pump. as far as fining some I would post WTB thread or look at ebay, I know if you have to buy it through Merc dealer its going to be $$$$ had to buy just a pulley it was $200/300 for it....

pressure relief valve
 

I have never heard of using a pressure relief valve on the water feed? Can't find them on Teague site?
So you had yours before the pump and Randy had his after the pump. Where did u dump it to? Out a dump hole in the transom?
I had the stock 502mpi with the small SC with a Hull P/U and strainer..
Where can I see one of these?
Thx
Larry

I'm sure Teague has them, I boat on pretty flat water so placement wasn't critical. If your leaving the water a lot & don't want to damage your strainers you can mount them in the strainers or the inlet side. I mounted my dumps next to my bilge outlets. You can get an aftermarket pump with bracket & just install your pulley, they have them like the older bronze pumps that are adjustable in the bracket but they are $$$. I can't believe it is that tough to find a pump/bracket assy that will work for your set up, p/s is a different story but not a waterpump. Randy

Here is my pressure release valve setup with a Merc pump and thu-hull pick up and strainer. In the charge cooler, that T with a gauge. Basically just a spring valve that dumps out the side of the boat. The water pressure gauge is about useless there, worked fine when setting it up, but once the hatch cover is installed, ya can't check it. An in dash gauge works the best.

http://www.altfuelsgroup.org/picture...922_160927.jpg
Pressure Relief Valve

http://www.altfuelsgroup.org/picture...922_160918.jpg
Sea Strainer

I also run that big block serpentine pump on this diesel. Mounted by a custom bracket someone fab'd out of aluminum. Works great, never an issue, but a real pain in the ass to change impeller each year...

so is the pressure valve the brass portion in the pic?

Yeah, the brass valve with the small hose coming off it.

water pressure
 

Cool, thx everyone, learned a lot.
I will run a regulator preferably off of the back of intake for 20 lbs, and then one in line be for the intercooler at 10 lbs.
Larry

If you are still looking for the sea water fuel pump setup I have a couple different ones with new bearings and seals.

still looking for a blue pulley 500efi seawater pump with pulley and bracket
 

About to buy new. Bracket 818368T1 with pump (no fuel outlet) pn 807151A22 and the associated pulley. My option is ti buy the bracket on eBay for 180.00 and a pump and pulley from harden marine for 370 for the pump and 175 for the pulley yippe