I replaced the stock pump on my 2004 496 HO with the stainless Hardin unit last spring and ran great all last season. Assumed I was golden for a few years. Winterized by pumping antifreeze into the seawater section as I've always done. First startup on the muffs yesterday and no rawwater from the exhaust, not a drop.

Removed and disassembled the pump (always fun). Impeller and pump look like new. Stuck a garden hose into the inlet hose and water came spraying out the outdrive inlet holes so no blockage there. Stuck the garden hose into the outlet hose and water came out both exhaust as expected, no blockage there.

Now what? Any suggestions?

Did you remember to release the air in the lines so the valves
Close . Remember 496 gets drained with an air pump

Yep, I've never used that drain system but I did check that they weren't pressurized and that no water was draining into the bilge from the valves.

Try priming the pumps by filling everything with water. Hard for impellors to create enough vacuum to draw water through to get things going. My guess, not familiar with your set up. I had one motor do this, refusing to pump water, I blipped the throttle and woosh, worked.

Rick

I found that blipping the throttle worked for my 496s every time. My engines did the same thing all the time.

+1,,also when you have the ears on the drive make sure the stream of water is in the up position..

Or, if you have a ramp close by just back it down and run it without letting it off the trailer.

I found that with my old 496 and now even worse with my 525efi that the exhaust gets VERY warm when running on the hose. Doesn't happen when the boat is in the water.

I try to limit my flushing and keep the rpms low. I'm on a well so the water is usually pretty cold, but the pressure might not be that high.

BTW, I still don't think we ever ran across each other on the water yet.

I've replaced the impeller and re-assembled the pump anyway since I have it out of the boat. I plan to re-install it tomorrow and try again, first without the outlet hose attached. I re-checked the inlet path and it's clear of obstruction and air leaks so it will have to work if physics are still the same. Jeff at Hardin was very helpful after speaking with him today.

I live right next to the boat ramp on the Wicomico in St. Mary's county so I was definitely planning on doing exactly what you suggested rather than the flush muffs.

You probably have seen me at some point. I've been going to Fairview, Cobb Island, Gilligan's and Capt. Billy's for over 25 years and when I'm not there I'm at Tiki Bar in Solomon's Island. I'm ready to get back out there with this weather .

My boat did the same thing with both the stock pumps and the Hardin pumps. I always backed the boat in the water to start it because it did not want to pull water from LWP on a hose at all. Never saw any damage to impellers though.

My boat did the same thing with both the stock pumps and the Hardin pumps. I always backed the boat in the water to start it because it did not want to pull water from LWP on a hose at all. Never saw any damage to impellers though.


I've heard lots of people say same thing. I've never had that issue though but I should find out today.