Re: 496 sea water pump
 

word of warning on the 496 style pumps, if the housing is scored do not change the impeller unless it is bad, alot of times the new impeller will not pump due tp capitation because the new impeller is not shaped to the housing(thats the problem with the brass housing) if this happens the only cure is to replace the housing

Re: 496 sea water pump
 

Housing was in good shape. No scoring. Ran it this morning at the local lake and all looks good.

Even though it didn't draw water when I first started it, I back flushed from the top of the motor and from the out drive when the pump was disconnected. I got several bits and pieces of impeller from each direction. I'm glad this board is around to provide all the advice and tips for stuff like this!

Re: 496 sea water pump
 

Changed mine yesterday, top and back brass plates were slightly scored (really light scores). I figured it would not harm so I replaced the impeller. The old impeller was in good shape, it had only lost it's flexibility.

Are you saying that as soon as you see scores, no matter the degree it should be machined and brassed?

Here is a picture of the situation:

Re: 496 sea water pump
 

that may or may not cause it to cavitate 50 50 shot

Re: 496 sea water pump
 

Mmmm... I don't like 50/50 equations in boating... I'l call a machine shop tomorrow and see what they can do and how $$$ it would cost. I am also worrying about damage that could be done to the shaft assy by heat when soldering and planing the brass. A replacement pump costs 268$. At that price, I'd better just replace it.

I found different costs on the 496's Brass pumps depending on the engine serial number... The other model costs 500$ :eek: . The design seems a little different. What is the main difference or improvement over the 268$ pump?

Re: 496 sea water pump
 

There is a machine shop in Lake Havasu City, AZ that makes a shim kit for the scored brass housings. Contact Absolute Speed and Marine in LHC for the machine shop and kit..... The fix for the plate is to have it brazed and machined flat.

Re: 496 sea water pump
 

Do you know what type of metal the shim in the shim kit is made of? Shame they did not design this all out of stainless or plastic with replaceable stainless liners like the out board water pumps. Those are really durable.

Re: 496 sea water pump
 

Pretty sure its stainless....Might call Absolute Speed and Marine at 928 855 2252 to check on the detals.

Re: 496 sea water pump
 

My 03 496HO's, got their 1st impeller change this week, 143 hours, and every thing looked like new, replaced all just for GP. Normally this is an annual thing for me on my boats.
I skipped last year due to minimal run hours.

I always do my first start of the season IN THE WATER, not on a hose.
Now I have 2 emergency spares...
My 2 Cents.
Bryan

Re: 496 sea water pump
 

Been lurking for some time now and have received lots of helpful advice. So, thanks to all that have posted their efforts for the rest of us to gain from.
Anyway, just put a new impeller in too. loads of fun! I would think Merc could come up with a better design or easier access.
Question is:
Can you hook up a hose to the Bravo 1x to test run? it has the littlest pick up holes in the worst location.