How to Change Your Impeller (Mercury Engine)

[jmstige]

Well, I think I've answered my last question...

The guy at Mercury Marine over at Pier 121 - he took one look at the impeller and housing, then came back with a housing kit.

He said that if you don't catch it before one of the blades come off, then the housing may not need replacement but if the impeller gets to the state it was in - then you need to replace the housing also.

He also said that the missing blade was most likely in the thermostat area and I should fish it out from there.

Charged me $100 for the replacement impeller/housing/bolts.

Anyone have any opinions on a) the price paid for the replacement kit or b) the comment about the missing blade up in the thermostat area (easy enough to check I guess).

[Jason B]

Well, I think I've answered my last question...

The guy at Mercury Marine over at Pier 121 - he took one look at the impeller and housing, then came back with a housing kit.

He said that if you don't catch it before one of the blades come off, then the housing may not need replacement but if the impeller gets to the state it was in - then you need to replace the housing also.

He also said that the missing blade was most likely in the thermostat area and I should fish it out from there.

Charged me $100 for the replacement impeller/housing/bolts.

Anyone have any opinions on a) the price paid for the replacement kit or b) the comment about the missing blade up in the thermostat area (easy enough to check I guess).

Sounds about right. Make sure you find that missing fin.

[TigeDuner]

I thought I had read that on the newer pumps on the MP engines, the pump could remain installed and only the cover of the pump was removed to replace the impeller. I need to change mine in the next couple of weeks and hope this is the case. Should be easier if I can get to it. We have a 6.0 and it seems like there is alot in the way to even see the pump.

[mtnsmith]

I replaced mine this summer, 2005 5.7 liter/340 hp...I think it has about the same room for working as the 6.0 liter. I only had to remove the cover and use one of those little hook tools that they make to remove the top of a paint can. It worked well to hook the inside edge of the impeller and work out.

[TigeDuner]

I found the pump on the front of the motor at the rear of the boat. The cover is held on with four small bolts. I assume that I do not need to remove the pump, hoses, or belts, just remove the cover and extract the impeller.
This will be tomorrows project.

[illiniboarder88]

FYI, I changed my impeller today, and I learned that while my boat is a 2000, apparently the engine is not. The dealer told me this is not uncommon, but the only reason I mention it is that I ordered the impeller in their book that was for a 2000, and it did not fit. The impeller that fit was for older models. On another note, this tutorial helped a lot. It made the job quite easy!

[samw]

I just took my pump out. It was pretty straight forward. I have a pm into Andrew I impeller didn't come with the O rings. So do I have to replace them??
Also I have some scouring in my housing so it looks like I need a new one. So where do I locate one of them beside going to a dealer.
Thanks

[Wakemaker]

Great write-up

Great write-up! Just completed it myself for the first time and the info and pics were great. A few thoughts: I also considered trying to replace without removing the unit, but can now say that removing the belt and the bracket is quick/easy and trying to remove just the back cover is an issue with figuring how to back the hoses off and not being able to "see" the inside. The three bracket bolts came off no problem and I was able to pull the unit off the hoses easily just loosening the hose clamps and moving it forward, so I could work on the impeller on my bench. Also, the step where they suggest making note of the bolt locations is really important. I did a quick pencil drawing to remind myself how the wear plate sat, how the bracket sat, and which holes got long bolts that go through to the bracket and which get the shorter ones, otherwise it could be tricky to re-assemble correctly. Another thought, I marked which was the bottom/out portal and which was the top/in portal which also helped on re-assembly. I used this website: www.mercruiserparts.com to run my engine serial number and get part numbers, but got lucky and found it local. They also sold the o-rings separately. About 29 for the impeller and 2.50 for the o-ring. Thanks again for taking the time to provide the instructional.

[flyboy]

The pictorial looks nothing like my 05

Can someone direct me to R&R the impeller on a MP 340 Vortec?

Ok..found mine, but it aint got no teeth left..how does one extract it from the housing though?

[chpthril]

The pictorial looks nothing like my 05

Can someone direct me to R&R the impeller on a MP 340 Vortec?

Ok..found mine, but it aint got no teeth left..how does one extract it from the housing though?

Yep, as the title indicates, this is for the Merc engine. The Marine Power is the 4th "sticky" down, 3rd below this one, and is titled "Change your Marine Power (Jabsco) Impeller"

http://www.tigeowners.com/forum/showthread.php?t=6303

[chpthril]

The pictorial looks nothing like my 05

Can someone direct me to R&R the impeller on a MP 340 Vortec?

Ok..found mine, but it aint got no teeth left..how does one extract it from the housing though?

Easy when the teeth are gone, grab it with a pair of pliers and pull it out.

[flyboy]

Easy when the teeth are gone, grab it with a pair of pliers and pull it out.

How important is it to find ALL the teeth? And where would one look for them? I feel a few behind the impeller and I removed the bottom hose, but I'll need to remove them once I remove the old damaged impeller.

TIA!

Edit: Sorry, I posted this in the wrong thread!

[pwhicks]

This worked great for my 03 22V. 7.5 teeth were in the housing. The last .5 was at the front (bow) of the engine inside a 6" cylinder.

It takes a couple seconds to loosen the serpentine belt to gain access to the mounting bolts. It is very easy to remove and replace the housing since the lower mount is a threaded shaft from the engine block versus a bolt like the top mount. That made the job easy on my work bench.

Thanks for the help! I now have the right spare with me if I need to do this away from home.

Paul

[Yessup]

I am so grateful for this thread. I changed my impeller today by myself . I am not very mechanically inclined, and the job went very smooth. I have done it before with my mechanic cousin looking over my shoulder, but today I was solo!!! Thanks again for the helpful tips!

[TigeDuner]

Just think of the money you saved. I paid almost $2oo bucks the first time I had it done near the lake after being towed in. Now I change it annually for $35.00. Good job.