First Time Changing 496 HO Water Pump
 

Bought a new to me 2005 Baja 25 Outlaw last year with a 496 HO and its due for its 2 year seawater impeller replacement. Can anyone point me in the right direction to a step by step procedure on how to do this? I have tried searching and have found bits and pieces, mostly that gen 3 cool fuel module is a PITA, but have not found a great source yet. So far from my researching it looks like the steps to do it are to release the serpentine tension using the tensioner pulley, remove belt off of sea water pulley. Then some people zip tie the belt, while others remove the idler pulley?? Then remove the inlet and outlet hoses, which is apparently difficult because the cool fuel module is in the way, and then it can be unbolted from the motor and removed.

Any advice, or real world experience would be appreciated for this newbie. I would like to learn instead of paying someone several hundred dollars every other year if possible.

Thanks!

Its not that hard to do, but if you have the single or three point drain system you will have air lines connected to the back side of the pump.

So far as the belt, I wouldn't worry about it, if you get in trouble after replacing the belt, that question is easy to answer. Remove the belt, the hoses and air lines and then put it on a bench to replace the impeller. Note the direction of the impeller when its removed so you can put it back in the same direction. Have some glycerin available to lube the impeller, or if its going straight back into the water you can use soap.

Thanks for the response. Do you by chance know what size the bracket bolts are, and the tensioner nut?

Memory not the greatest, but the jam nut on the tensioner is 5/8, and think the center stud is 5/16, but I usually use a crescent wrench on it

The bolts and nuts holding the pump housing is I think 1/2, but may be 9/16.

Have done it many times but never thought of remembering, always had a full set of stuff with me

Thanks! Not a big deal just figured the less amount of times I craw in and out of the engine compartment the better. One last question, is there any procedure in order to prime the pump? What do I do about the new impeller / pump being full of air and no longer water?

Thanks again.

back it in the water and start it

Sounds easy

if you had the 23 outlaw with a Merc 496 you would pass on the job - I promise you that. Half the engine has to come apart or just pull the whole engine. Its an all day job for the 23. The 25 has more access but it is not no walk in the park either.

Can we do an over / under for hours it takes you to fully complete the task in hand and all correctly ?

2005 was right at the year the 496 set up changed a lot but -- depending on how late of a 2005 year model it is. - it goes by engine serial number for exact set up and parts installed not by hull year model.

But you have the Gen 3 cool fuel system and there is no jam nut nor bolt tensioner on the port side of the engine. I do know exactly which set up you have.

My over / under is 6 hours from start to complete finish and possible 7 to 8 hours after running it to make sure it is doing well with no water leaks.. So who says under the 6 and who says over the 6 ?

Access to the motor and underneath the motor is actually one of the reasons I raised my motor 3”. First season I had it I dropped one of the blue drains plugs underneath and it took me and my wife fishing for it with our feet to get it out! They’re definitely sunk in there

https://cimg2.ibsrv.net/gimg/www.off...fe0bb4dab.jpeg
https://cimg3.ibsrv.net/gimg/www.off...c37a30b46.jpeg