2000 7.4 Litre MPI

[McNally260DA]

Thanks everyone for the help. I took the boat out of the water and will be repairing it in the driveway. It seems that there are two ways to approach this. One is to remove the whole unit with the bracket and rebuild the pump on the bench. The other is to just remove the housing from the back of the pump leaving everything else in place and rebuild and install. The unit is fairly easy to get to although not real easy to see if you were rebuilding the pump in place. If anyone has done this could you please advise? It's a 2000 7.4 litre 260 Sundancer.

[Lazy Daze]

Take it out and do it on the bench. We're quite lucky (with our model) to have very good access all around the engine. But, even so, it's just that much easier on the bench.

[McNally260DA]

Thanks Lazy Daze. Thats the way I'll do it. This is a maintanence item so I want to learn to do it myself. I boat about 75 Hours a year in the St. Lawrence River. Should I do this every year? The river is like bottled water but I don't want neglect preventive maintanance.

[Lazy Daze]

Nah, I wouldn't do it every year. You can't go wrong by doing it, but it's likely overkill. In fresh water, with minimal silt/sand, you should be good for about 3 years. I absolutely wouldn't recommend this, but we get boats in all the time (from local lakes) that haven't had the impeller changed in 6-7 years + and they're still flowing good water. I can even remember a few times when I've asked customers (owned their boat for about 10 years at the time) "when was the last time you changed the impeller". Their response... "What's an impeller"?

Jabsco makes a better pump, if you're interested. It's a bit pricey, but it's rebuildable and made from bronze, not plastic.

[McNally260DA]

Thanks for the info. I'll pull it this weekend.

[Bob & Sue]

A couple tips when you install the impeller into the housing use dish soap as a lube don't use any oil products on the impeller it will cause it to swell and seize up I did this last year. Also it's a lot easier to remove the whole bracket assembly and don't forget to mark which hose is intake and exhaust. I also use Loctite 242 threadlocker on the bracket bolts. There's a lot of videos on the web to show how to do it.

[mwph]

One last thing; Your engine is newer than mine so this may not apply, but... IF the pulley itself is plastic, replace it with a metal one while its on the bench. My plastic pulley, (again 1998), failed, leaving me dead in the water. Its an easy & cheap enough job on the bench.

[McNally260DA]

Thanks for the tips. The pump housing is plastic but I think the pulley is metal. I don't think the bearings are seized up it feels more like the impeller is preventing the pulley from turning. When you try and turn the pulley by hand it feels spongy like a rubber impeller might be twisted up in the housing. Hope so anyway the rebuild kit is alot cheaper than a new unit.