I thought changing an impeller was easy?

After reading all about the importance of changing the impeller and how simple it is I decided to tackle the problem myself. I have a V-drive (Indmar) and took a look at the engine. I followed the water intake and the hose goes from the bottom of the boat, through the V-Drive and eventually to the "front" of the engine. The problem is the "front" of the engine is actually in the rear of the boat. Also the exaust risers and pipes cover what I think is the water pump housing. So am I wrong or is this where the impeller is located. It seems such a pain to remove the exhaust system just to get to the impeller.

Thats why v-drives are such a pain to work on! Enjoy

I don't think it's that difficult, the cap is pretty accessable. I have Indmar on my MC and, while it's not on the top of the engine, it certainly isn't something you have to disassemble the exhaust system to get to...

Haha, not that i'd ever refuse a V-drive for my DD, but i find it funny that if i ever fry an impeller i can change it out without leaving the drivers seat. Is it really that tight in there, can't you remove the side panels of the engine compartment and hop down there and get to it from the side?

I may try to remove the side panels of the engine compartment. My boat is in storage so I can't take a pic. but the exhaust definitely blocks all access from the top.

Mark- did you access the pump from the side?

http://www.globerubberworks.com/

these impellers look interesting.

A.P., don't confuse the impeller housing with the actual water pump. I know it is harder to get to on V drives but the impeller in the "raw water pump" should be on its own bracket with a fan belt going over it. The water pump would be directly on the "front" of the engine and rarely needs servicing. The impeller gets the lake water up to the actual water pump and then it takes over from there, circulating it through the engine. Perhaps we are talking about the same thing.

I changed the impeller on my vlx. It was located at the stern side of the motor, a few inches below the deck. Four or five bolts held on the cover plate. A ratchet worked best for those. after removing the cover and the old gasket, I used pliers to pull the thing out. It was a major pain. You can buy impeller pullers, but I also hear you can crank the engine (once you pull that cover off) and the impeller will work itself out a bit.

Putting it in was a bit easier, I used a bit of binding lube to help it slide in.

My vlx has hard tanks, which made it tough to stand back there. Apparently, some people take the tanks out to work on the engine, and others take the whole engine cover off.

i don't know if its different on different indmar models but on my mx plus its a crank driven raw water pump right on the front of the engine. PCM's are fan driven, the 310 indmars are crank driven(as far as i know). So it doesn't necesarily have a fan belt running over it.

This is where the impeller is located

yep

You guy's have it easy. Mercruiser puts it in the bottom right side of the motor. To top it off they block it with the fuel filter and pump. Took me 4 hours to get my impeller out and 2 hours to put it back in. Now that I have it down it should only take 3-4 hours to replace it next time. Just crazy for something that needs to be changed every year.

Thomas thanks for the link seems like a better soulution.

www.Wake-Me.com

yea i've seen mercs, seems like an awful place for it

Why every year? Just replace it when it is toast.

if you replace it every year you are much less likely to have it go toast when you're out on the water

DJL we put 136 hrs on our boat from June 16th to Oct. This year we will put much more than that on it. An impeller is only good for around 200 hrs in my experience.

plus toasting it requires backflushing the cooling system to get the pieces out, so if you can keep it from disintegrating and blocking some of the smaller cooling passages in the block you are less likely to fry your engine, easy insurance.

You really can't go by hours on the impeller. They are more effected by getting dried out than being used on a continuous basis. Just remember that if it does go out while you are on the water it will be at the worst time. I always keep a spare in the boat. I have had to replace them twice while I was on vacation. The V-drive does such. I took the side panel out and it took about an hour and a half and more flexiblity than I was probably capable of.

Phaeton was your pump body scored? My merc one was showing pretty bad marks after 120 hrs.

i have a merc right on teh front left very easy ta get too. i have also seen a boat almost get fried from an old impeller. don't risk a big money engine on a 15 doller part

OKAY HERE'S THE SECRET AFTER REMOVING PUMP COVER, GREASE INTO THE IMPELLER SPLINES WITH SOME SORT OF MARINE GREASE I RECOMMEND MERCURY 2-4-C NOT TOO MUCH BUT TRY AND SQUEEZE SOME ALL AROUND IMPELLER, REMOVE KILL SWITCH LANYARD AND BUMP OVER MOTOR A COUPLE OF TIMES, THEN GRAP YOUR NEEDLE NOSE PLIERS AND YANK IT OUT, BEFORE INSTALLING NEW ONE GREASE INNER SPLINE SHAFT THAT THE IMPELLER RIDES ON NEXT TIME IT'LL BE EVEN EASIER, NOTE THE WAY THE FIN'S OF THE IMPELLER WERE BENT, INSTALL NEW IMPELLER SAME WAY

I just did this last weekend for the first time on my Indmar-powered Supra V-drive. After several frustrating hours on Saturday and quick 15 minutes on Sunday, here's what I learned:

1. Soapy water doesn't work as a lube for this operation. But, silicon spray lubricant works WONDERS. I even got an extra can to leave on the boat for emergencies.

2. Turning the engine over -- and over, and over, and over -- only moved the impeller out about 1/16".

3. Get a small pair (6" or 6-1/2") of needle- nose vise-grip pliers. I picked them up at Autozone for $9.99. Use them to grab the impeller with one jaw on the metal hub (on the inside of the impeller) and the other jaw on the outer rubber part, between two vanes. Tighten them down and wiggle the impeller up-and-down and side-to-side a little as you pull on it, and it should come right out.

Darren no there was not scoring in the housing. Sand maybe?

My impeller blew out on the water last summer. 10 minutes in-between sets and a brand new one was in. A plus in the DD column.

Yea when i took mine out at the end of last year only about 2 of the rubber vanes were intact, the rest were all busted up, guess i got lucky. When i went to take it out i was having trouble but sprayed some lube on the splines, turned to motor over once and out it came, of course its pretty accessible being an indmar dd.

AP, I found it easier with the side panels off, I have the same engine in a VLX

Thanks for all the help! Sounds like it still isn't as easy as I thought it would be.

ITS NOT HARD

I have been following this thread because I needed to change mine out this year. I got some quotes (around $200) and decided to try it my self on my lunch break today. I have a 98 Centurion elite v-drive with a Mercruiser.I'm not unfamilure with having a wrench in my hand but I am not a mechanic. It looked intimidating at first, but I had the pump on my bench in 15 minutes. Its not hard. Here's how it went.

1. Remove the side compartment board.

2. Unbolt to fuel/water filter from the bracket.Two bolts, no need to take off the lines. Just move the whole thing fore and aft as needed.

3. Loosen the clamps of the 2 hose's. remove the long hose. the short one won't come off. its to short to manipulate.

4. Loosen the belt. Its the pulley just above the pump and filter.

5. remove the pump. Don't mess with the pump housing bolts. Remove the 2 bolts that attach the bracket to the engine block. Now just manuver the entire thing out. It will slide off the short hose at this point. You will need to move the fuel filter foreward do get it out. Take it to your bench and disasemble the pump. its easy.I aslo made a diagram of what way the impeller vains pointed for reassembly.

I'm picking up the impeller after work and will put it back together tomorrow at lunch.

jesus, that sucks, definitely not the standard indmar "10 minute between set change"

I know that you are supposed to change out the impeller every year, but how do you know when it "blows out" while on the water?

just a tip after getting old impeller off put some plumbers putty (lube) on the splines. its made to not come off even in water.

Daniel, the impeller supply's the raw water to the engine's cooling system (or raw water to the heat exchanger in a closed cooling engine), either way, if the impeller blow's the boat will overheat due to lack of flow through the cooling system. In terms of knowing when it is about to blow, i guess if a bunch of vanes got torn up it might move less water and the engine temperature might rise slightly, but i'm not sure there is any way of knowing an impeller's condition without opening up the pump and pulling it out.

shoot you guys are complaining about V drive impellars... try an I/O once and youll appreciate your v or d....not to say they are better boats but that for this particular item it sucs on an I/O

If the impellar does fry how do you backflush the cooling system?

Too easy on a mc dd. Remove 4 screws, take off cover and remove inpeller. Install new one and put screws back. Take off tranny cooler hose and remove any debris in the filter, put hose back on. Takes about 5 min for the whole thing.

that's just to replace the impeller and clean the tranny filter. The tranny filter is before the impeller so pieces don't get stuck on that. Still a good idea to check it though, could have been the reason the impeller fried. Backflushing involves running water from the back end of the cooling system out the front end to remove any pieces. I'm not sure which hoses you remove to do it on different engines, but i'm sure somebody does on here...

I have a direct drive but I still find it easier to remove the whole pump and then extract the impeller at the workbench like Brad said. Also I always grease the impeller and spline with white lithium water pump grease - it make the process a whole lot easier the next time.

Where is the tranny cooler hose/filter on a Black Scorpion?

jimr, i take it you have a pcm or merc engine?

It's a Merc.

yea indmar's are much easier than mercs and pcm's

5 minute joobie

After you pull the cover (4 screws) spray some wd-40 in there and then crank the motor over for a second. Then take 2 pair of needle nose pliers so you can pull evenly and the thing slides right out every time. my 2 cents.

thomas, thanks for the link to Globe. Someone was telling me about these and I couldn't remember the name. They guarantee you can run them dry for 15min!! I'm going to be replaceing mine with one of these.