volvo penta MD2030 impeller question

bobdamiano · Dec 12, 2010

Hello all,

We have a Pearson 34 which was unfinished when (then) Cal-Pearson folded. It was later finished and sold by Bristol Marine. They put a Volvo Penta in it. The engine has very low hours with only light usage for two seasons (one since we've owned it). I'm embarrassed to say that I've never inspected the sea water impeller - until yesterday. (Actually judging by how the green paint was still uncracked around the screws, it looks like the first owner didn't either)

I was surprised to see this brass insert along the wall of the housing as seen in the photo. As you can see, it completely bends over the fins of the impeller as it turns which I would think would tear it to shreds. Apparently not though. I've looked at lots of photos on the web of other housings and have only seen this in the Volvo. Does anyone know why Volvo does this and what the purpose is?

While searching, I also learned about SpeedSeal covers. I'm thinking that looks like a good idea.

Thanks in advance

mitchbrown · Dec 12, 2010

Hi Bob

your pump is the same as every other neopreen impellar pump. As the impellar turns past the plate it causes it to compress and squeze the water out of the port on that side of the housing, then when it expands on the other side it pulls water in from the port on that side. I change the impellars on my yanmar every 3 years and they still look new when i replace them. Average 100 hours per year.

Mitch

TejasSailer · Dec 12, 2010

We have a speedseal on our MD2030 and are quite satisfied with it. The MD2030 apparently used two different pumps, and you'll need to be able to describe the cover when you place the order.

BTW, we change the impeller annually at much lower hours.

BELLATRIX1965 · Dec 12, 2010

As Mitch correctly points out, your raw water pump woudn't work without that brass plate - in fact, that plate (often called a cam) is a replaceable wear part - keep an eye on it! The extreme flexing of the rubber impeller accounts for the frequent failures and the recommendation to change it out annually (I agree with that suggestion). What is wierd about your photo is the fact that one vane is going in one direction, and the other vane is going the opposite (the two that are in contact with the cam plate). They should all be going in the same direction - strange - the engine must have rotated slightly in the opposite direction?

Even more important than the speedi-cover is to have an impeller puller and a spare impeller&gasket on board. They are not cheap, but if you have to change one out in a hurry - priceless! (pretty handy for routine changes too - you can do lots of damage with screwdrivers!)

JABSCO SMALL IMPELLER PULLER #50070-0040

bobdamiano · Dec 12, 2010

Thanks for all the help folks. Makes perfect sense now. I just never noticed the cam before in other boats. Then again, the only time I saw inside a pump was during a class with a bunch of other students. Didn't get that close of a look.

talbot · May 1, 2011

Part number for Volvo MD2010 impeller

Based on the picture below, I have this identical pump on my volvo 2010.
The part number on the impeller reads volvo 17 on one side and 3586502 on the other.
But there is no match on the internet for it.
Anybody have an idea on the correct part number?
BTW If I search "volvo 2010 impeller" I get a different looking impeller. This is what was sent to me by a dealer last year and it is much smaller then the one I have, so is the gasket.
Thanks
Talbot

volvo penta MD2030 impeller question

Attachments

Top Contributors this Month

Recommended Communities