Raw water impeller

Glassguy54

I just bought a 2007 246Captiva bow rider. This has a Mercruiser 350 Mag MPI w/ Bravo III. With the limited access to the engine, my question is,"How in the world does a guy get in there to replace that impeller?" 

Black_Diamond

Get the mercury shop manual, worth the cost to have. You need to take the belt off, then the pump. Word to the wise, replace it or it will go out.

Tsquare

The 246 has a removable floor panel for access to the front of the engine.  The seats must all be removed and relocated.  The 246 usually for a sea water pump exchange/impellor change 3 hr max. 

Dream_Inn

Yes, definitely pull the entire pump first.  The hoses in the back are usually what makes it difficult for initial removal (lube them inside before putting back on, makes installation much easier).  Also, when reinstalling the new impeller, use a good wire tie to help keep the impeller in the shape needed to push in.  As far as access, it sounds like Al hit it right on.  Good luck!  (& yes, change it out now)

Babyboomer

It's in the RBO Archives

http://www.outdriveshop.com/rebuild_bravo_raw_waterpump.html

Glassguy54

Thanks to all who have responded to my query regarding impeller replacement. This is my first Rinker, which I have only had since tuesday. I've owned other boats in the past, but access was always easier. This particular 246 Captiva I have is a 2007 model, and I have searched, in vain, for the above referenced removable floor panel. This deck is a seamless glass construction where the lounge seating forms a bulkhead in front of the engine. I would have to take out the removable cooler, then take a rotozip to cut a large hole through the bulkhead to get any better access to the front of the engine. I'm not keen on this approach! It seems the only solution is to try to squeeze myself down along the starboard side of the engine and try to get at it that way or else hang upside down! How do the certified service techs do it? Thanks again.

brianluck

Start takin yoga, you will need the flexibility, my 300fv requires me to be a contortionist in the bilge.

Babyboomer

Now you know what jockies do when not on a horse )

Black_Diamond

@brianluck: great statement.  you do have to be a contortionist at times to work in the bilge and other places!  What I need is like an 8 year old with all the know-how and strength to do the jobs I need.

Dream_Inn

BD, my son is 10 and the other week in someone else 342 we had seriously thought about getting hiim to change out the spark plugs!

Tsquare

Hold on a couple days,  I have a 246 with a Bravo III 350 mag coming in for service and I know it will need and impellor.  The more I think you are right, the floor does not come out, that is on a 232.  Remove the black plastic tub and craw into the motor cavity.  I usually pull the hatch rams and lift the cover real high.  Anyway, I can give a much better assesment after the weekend.  Al

Glassguy54

OK, thanks Al,

I won't attempt to tackle this until you post what you have learned. I did manage to get down in there to get the lay of the land, as it were, and I have discovered a large rectangular casting, resembling a big black brick, under the alternator which has what I believe is a fuel line coming into the front of this unit from the fuel tank. There are two hoses going into the back of the unit that are apparently just pressed on (no hose clamps) and on top of this unit there are what appear to be some sort of service access covers, screwed on. The forward one has sort of a handle on it and the rear cover is kind of an inverted pan-like dome with an electrical connection on top. I cannot identify a pulley driven pump housing unless it would be buried under this brick & alternator and thus virtually impossible to get at. The engine sits very low in the bilge deep between stringers. The fuel tank is maybe a mere 2 or 3 inches in front of the serpentine belt and crank pulley ,etc. For something that is recommended to be replaced each season, it seems like a poor location for the raw water pump! Or they could have made an engine hatch cover more like on a Crownline or Chaparral, that exposes the entire front of the engine. 

TikiHut2

Sometimes cramming a camera into spots you can't see to get a few pics will help you visualize how to pretzel yourself or a hand into an otherwise impossible spot. Posting a couple pics will also help others recognize what you are dealing with. That sounds like a tough one. Al will know if it's possible but pulling the engine isn't as dreadful as you might think....easy for me to say sitting here.

This sounds like a perfect job for Undercover Boss. Let the engineer who thought that one through give it a try and we'll see if the design doesn't change instantly.

Sure hope it turns out easier than it seems. Mike

Tsquare

Well first of all the Sea Water pumps are located and designed my Mercruiser.   The sea water pump is located on the front of the block starboard side of the crankshaft.  The Serpentine belt will have to be removed.  Yes these are a pain in the a$$, but are replaceable.   I will post more tomorrow night.    Oh, the "black Brick" glass guy saw is the high pressure fuel pump.    Al 

Dream_Inn

& yes, it is down under the alternator & definitely pulley driven.  If you have only 2 or 3 inches in front of the pulleys, that will be extremely tough!  I did this on a '00 340 and it had about a foot in there and that was the worst I had ever changed.  Also, that box (fuel cooler) makes it very tough as well.  Hopefully the pump housing doesn't have a little tab on it which makes it extremely difficult to pull off cause it causes it to hit the main crank pulley (you'll know what I mean if you get to that point).  Good luck is all I can say!

Babyboomer

VIDEO

http://www.youtube.com/watch?v=UxLfF2abE_o

raybo3

Awesome vid Boomer....

Spacelord

nice vid.. but the 2 piece raw water pump is a little different.  No long bolts for one thing.

This one looks a little more like what I have in my 05 270.  I need to pull the bracket etc similar to this video.

https://www.youtube.com/watch?v=eZYJq746awc

Babyboomer

Spacelord said:

nice vid.. but the 2 piece raw water pump is a little different.  No long bolts for one thing.

This one looks a little more like what I have in my 05 270.  I need to pull the bracket etc similar to this video.

https://www.youtube.com/watch?v=eZYJq746awc

Thanks for the update never saw that one I added the link in RBO Archives this is how we build a library and we try and post these kind of links to help everyone out this is what RBO was and what RBOC will become.

Glassguy54

I just watched the video posted by Spacelord and I am convinced that this is the set-up I have on my 2007 246 Captiva, only there is much less room to work with in the 246. Apparently the big brick like thingy is the Gen III cool fuel module with the raw water pump next to it under the engine block. What a bummer! As a last resort, what is a guy looking at in terms of cost to have a certified marine mechanic pull the engine to replace the impeller?

Babyboomer

Good Question for Tsquare

Tsquare

Ok, the job takes no more than 3hrs start to finish.  We just completed a 246 with a 350 mag

1st remove the **** pit seats and bases as well as the back wraps.

2  Remove the removable panel located directly in front of the motor

3  The convoluted foam will need to be trimmed to remove the fiberglass panel

4  Remove the hatch ram struts and use a long pole as a prop to open motor hatch higher

5  At this time you will need to be in the motor compartment as well as in the cockpit working back and forth

6  Remove the belt assy, pay attention to which direction belt is running

7 loosen hose clamps and hoses from sea water pump

8 Remove bolts for sea water pump

9 once pump is on the bench disassemble pump and replace impellor

10 Reassemble in reverse order. 

This engine does not need to be pulled to service this pump.  We intergrated the removable panel to allow for such access during prototype stage of the 246. 

Good luck  Al

Capt_Steve

Pay attention to the man behind the curtain!

Glassguy54

Thanks for the tips, but you're going to think I'm some kind of nut!  I removed the "J" shaped seat back that forms the cockpit lounge and unhinged & removed the seat cushion over the removable cooler. I got real excited because there was a panel section that is held in with screws. OK, so I took out the screws and lifted off the 30"w x 17"h panel that only goes from the top of the backrest down  to only about half way to the floor. Guess what? Solid glass behind! Apparently this panel just fills in a recess in order to make it flush for the seat back cushion. Is my 246 an odd ball, one off? 

 

Tsquare

Once the panel is removed, you should have access to the front of the motor.  If this is not cut out from the factory, someone skipped a position and covered it up with foam.  I really don't have any photos of what it shold look like.  Sorry.  Al;

Black_Diamond

Got to love the improvised assembly used sometimes!  Every boat has quirks and seems no two are quite the same.  Personally, from an engineering point of view, that drives me nuts.

Glassguy54

Could a Volvo/Penta type raw water pump, the kind that is mounted on front of the crank pulley, be retro-fitted onto a Mercruiser for easier servicing?

Dream_Inn

Wow, I think some pictures are needed here.  This is getting interesting.

Glassguy54

Interesting and frustrating!!! I will try to get some pictures on here so that others can see what it is I am trying to describe. If, as Tsquare mentions, some one at the factory forgot to cut out for the access panel, it seems like a pretty huge omission! How would something like that get past quality control? Or was it initially designed this way and then someone realized, "Ya know what? Engine access is a ****! Let's make a removable panel here!" I'm thinking my 246 is destined for a little bit of rotozip modification.

Glassguy54

I will attempt to post these pictures I just took..

#1 Cushions in place

#2 Cushions removed - panel visible in upper half

#3 Panel removed

No access panel to front of engine. So what gives?

TikiHut2

Take your pick. Bummer, but it's up to you to cut it out.

http://www.google.com/imgres?imgurl=http://www.popularmechanics.com/cm/popularmechanics/images/ee/oscillating-tools-01-0709-de.jpg&imgrefurl=http://www.popularmechanics.com/home/reviews/power-tools/4325505&h=480&w=600&sz=54&tbnid=8NWtS4P8NHPrEM:&tbnh=90&tbnw=113&zoom=1&usg=__WIWHcigIwQ5HXFxPqG9Y7W-JMrs=&docid=2x8Fvb0-Kb9LIM&sa=X&ei=4H2WUd28GZTU9QSoiYHICw&sqi=2&ved=0CHoQ9QEwAw&dur=3644