First Mistake Of The Season
 

Put the muffs on started the port motor & no water coming out the exhaust. Well then I hear the squealing. Thought @ first it was a dry pulley bearing or alternator belt noise. Then I realized it was pump impeller. Well needless to say I shut it off & sure **** pump housing was smoking hot. Well I thought you dumb **** why didn t you prim it first & this wouldn t of happened. So I got smart and primmed the starboard motor. Filled it to the top until I heard it running out the drive to the concrete. Fired it up with the muffs engine idling, & it would not pump water out the exhaust until I forced the muff by hand tight to the drive for like a minute & then it finally pumped. WTF, anyone else have this experience? On my old boats I never even ran muffs I ld just put it in the water & ran it but then again I was not so smart back then & apparently I still not smart.

So I see there is no longer an impeller in the out drive. This is a 28 Formula with a pair of 350 mags,2006. @ first I thought that was the issue but come to find out thats not it. So again WTF? I m thinking no body primes blocks now a days? But I think its a must or you will be replacing pump impeller's yearly. Any body have some
in site on my dilemma? Lost the whole fricking Memorial weekend. Signed one pissed off guy.

yes the impellor is just bad enough not to have enough suction. they sure dont seem to last anymore.

Do you prime yours every year or not?

I had a problem with my muffs skating forward with the water on and eng off. By the time I climbed in and got the eng started, the muffs skated far enough to partially expose the holes. Connected some safety wire to the muffs and wrapped it around the back of the drive so they couldn't skate forward, no more impeller squealing.

all impeller changes are 2 years max and worse if you do not use your boat - Impellers sitting they form a set. Just like your car tires that have not moved in months - they get a flat spot.

Impellers fold over in one section of the housing they sit in and will not prime very good upon zero movement for months -- for a jist.

Anyways at the beginning of the boat season every season its best to install impellers regardless what one thinks. Its a piece of mind and your volume of water flow is back like how it should be unless you have issues in the cooling systems elsewhere. Many used boats can develope other cooling issues as well. ie boaters whom never change out water circ pumps and t stats think they last 4 ever. is 2 great prime examples.

Anyways if one has side feed water pick ups for their outdrive apps === your best muffs on the market are in the next post. I have posted this before about the best water muffs to use. Been using these exact muffs for about 20 years to current. For all Merc and the newer Volvo apps.

side water picks ups. these will never move and aid in water flow using the water hose to run the enginehttps://cimg3.ibsrv.net/gimg/www.off...a848aa0575.jpg

next info is you most likely have Mercruiser engines and Bravo 3 for outdrives and that means you will have the brass junk Gen VII water pump assembly and that junk brass housing that scores up badly. Another reason why you did not prime water.

I have the fix kit for the scored GEN VII pumps for 50 bucks shipped

good to know,,I hate working on those pumps,,they suck.

Yeah, supposedly the pumps had been replaced just prior of my purchase. Didn't know about brass housings thought they were all cast steel.
As far as that style muff goes if they don't leak and you have 60 pounds house water pressure ,how could it not supply water throughout the block?
As long as the impeller is spinning water is going to get through out the block. But you definitely have a great point that impeller housing is oblong for lack of better description and like you said the impeller is bent over more on half of the side of the housing versus the other side of the housing and it will set and not want to go back to its natural position from sitting.

Problem I'm up against right now is I can't get down in the bilge to remove the pump assembly and I don't know if anybody can get in there unless they're very small person I think I might have to pull the freaking motor to replace the pump

I think I've got you beat BUP with those muffs . I've had my set for 31 years ! But I think it might be time to replace them though .
When it comes to cooling issues we all have our unique experiences. 2 seasons back the boat was pumping and cooling like a champ . Hauled it and went to flush it out 2 hours later and it would not pick up even a drop of water on the muffs.
Of course I was scratching my head . Later pulled the water pump off (and it's a B3 and it's always had the 'plastic' water pump housing) and 70% of the impeller vanes are gone .
Now HTF did that happen between the slip and connecting the hose 2 hours later ? ? These things are sent to try us .

When I went to buy the new impeller at West Marine here in Milwaukee the retail sales person said he had already sold six impellers that morning.