Impeller change Bravo 3.

Ian

Okay, first time to do this myself in the spring so looking for the smarter than me guys for some clarification.

2003 FV310 with 0M34xx serial numbered 5.0 MPI's and B3's. I see from the Merc site parts list and drawings I see that I have this style of pump:


I see I can buy a new impeller and mickey mouse ears shaped o-ring, another with 2 round ones but then also see kits with a wear plate, housing etc:

Based on the Merc info and reviewing a couple of YouTube videos, I'd go the first option but I question the wear plate use - it seems there is a need for it somewhere sometime but it doesn't seem to match with this pump. What am I missing? 

Dream_Inn

What you should need is the impeller with just the one o-ring.

As for the wear plate, you may not know what you need until you have it apart(is it worn enough that could cause a new impeller to loose suction). You also need to look inside the other side of the pump to see if there is wear as well.  If so, you may need to either go with a new pump such as Hardin and then get a wear plate.

My advice, buy the impeller and o-ring.  Take it apart and see how things look.  If not bad, just install new impeller and o-ring and try that out.  If it does not prime, then you will need consider options with pump and/or plate.  

I'll add that when I did my last one, I just bought the hardin pump and went that route.  Very happy with the decision.  

rasbury

So, if not familiar with wear on these pumps, it takes next to nothing for the brass pumps to get a little sand in there and wear grooves in the tops and bottoms. Maybe it's a FL thing and not much issue for you. I went round and round with mine but did not want to spend the money for a new pump (700.00) so I found on line a company that makes a wear plate for both sides of the pump and they make an impeller that is not quite as tall to make up for the wear plates on both ends and it has worked great- kit was 98 bucks I think it was....that wear is not where the blades run up against the pump but on the sides of the impeller.

reneechris14

Listen to the boys if you can catch your finger nail on the groves pump is shot. On the pic's above the 1st impeller has 2 flat on the inner hub( that's the one you need) 2nd pic has 1 flat on the inner hub older impeller that is used on the Hardin pump.
 Make sure the back if the pulley is dry some time the seal behind the pulley leaks(this is my case on both pumps) 350 mag 300 hours salt water boat.
 If the pump has groves you can get the impeller and wear plates like Ras did. 
 In the diagram above remove #19 +#20 pull pump of the stud and lower it down take a 10mm ratchet wrench remove the 6 bolts from the back and you will not have to take of the hoses.(if your space allows)

Ian

Thanks gents for the feedback. I will get them off first and see before I order parts anyway, I was just unclear as to where the difference in parts came in. Where we are is more greasy mud than grit and I don't have any flow or temp issues, it's just that I want to do them as I haven't and with a trip to NYC next summer I'm not risking it for $100 or so.

It will be a while anyway with only 3 weeks gone since shoulder surgery, a good spring exercise before she goes in the water along with a new head flush pipe pulled in to the tank.

@reneechris14 "(if your space allows)" - yeah right! You'd think with a bigger boat there'd be more room, at least I did until I had to get in there to do anything serious.

Dream_Inn

Good luck with the shoulder (I had surgery a few years ago, all good except if I sleep on that side all night). 

I've always had better luck just removing the entire pump off the hoses.  Just spray some silicon spray in the hoses before you reinstall.

I don't admire you with that new hose pull awaiting you in the spring!  (I just finished changing out 4 duck bills in the vacuflush and a seal in the toilet a week ago - oh man was it nasty!  I was glad at that time that I have absolutely no sense of smell)

Ian

@Dream_Inn - that's the plan - pull of the hoses and pump and have a look in a normal heads up position on a flat surface!

I am planning to do the hose in the earlier spring than later and still indoors so it's cooler - read: not fermenting from the warmth. Hopefully pull it in and swap quickly and stuff the old pipe. Tank is empty so while there's some scent left over hopefully minimized.

LaRea

For actually removing the pump:
1. Remove serpentine belt.
2. Remove idler pulley.
3. Remove pump and bracket (#16 in the diagram) as an assembly.  

Ian

Thanks @LaRea, I figured this would be the easiest path - pop it off, pull off hose and have a good look on the bench with some light and clean it up.