Re: [Amel Yacht Owners] Onan 6.5 MDKDP Water Pump Part Number

Bill & Judy Rouse <yahoogroups@...>


I did not mention the Speedseal Life, because I know nothing about it. However, your description makes a lot of sense and hopefully SpeedSeal has impeller improvement figured out..

Frankly, I have felt like I was a little "conned" by SpeedSeal with their first version. Not much to it unless you think that the thumb screws are revolutionary.

I hope that you will keep us posted on your results. I change the Yanmar at 500 hours and the Onan at 250 hours. Changing with these hourly limits, I almost always change before losing a blade.


BeBe 387

On Sun, Feb 15, 2015 at 8:59 PM, Germain Jean-Pierre jgermain@... [amelyachtowners] <amelyachtowners@...> wrote:


Hello Bill,

There could be a misunderstanding here. Speedseal produces 2 kits: standard Speedseal and the Speedseal Life.  I agree with your assessment of the original Speedseal but the Life unit is different.  

Speedseal  machined a recess into the cover and add a Teflon disk at each end of the impeller.  The end cap on the water pump is then sealed with a thin rubber gasket.  This is the type I have on the Volvo; I can report in excess of 1000 hours of use without failure using a 500 hour replacement regime.  The impellers show surprising little wear upon removal.  In my opinion, this is a much improved product.

When I talked to Speedseal about 2 months ago, I asked them to duplicate the latter design for the Onan.

That said, I also procured a second water pump… as per your suggestion.. and yes, I have a wet/dry vac on board.  (… a frequently used tool..) Your suggested procedure is too good to ignore.  :-)


Jean-Pierre Germain
SY Eleuthera SM007

On 15 Feb 2015, at 23:06, 'Bill & Judy Rouse' yahoogroups@... [amelyachtowners] <amelyachtowners@...> wrote:


I am a little late to this conversation. I am familiar with the SpeedSeall product as I have one on my Yanmar. I think it is 80%hype and 20% product because all it really is, is knurled thumb knobs that replace bolts...yes, they give you a new end-plate with 2 holes and 2 slots, rather than the stock 4 hole end-plate, and supposedly they have a great extractor tool, but...the vice grip tool that Gary Silver designed and posted a photo of is 100 times better.

BeBe (2003 - 387) has a 2002 Onan Model 7MDKAV, SN# JO10296057. A SpeedSeal solution will not work for this Sherwood water pump because of the way the pump is designed.

However, that said....

I believe that the best way to deal with impeller changes on this pump is to remove the pump. It is very easy to remove (two bolts/nuts). Once removed, it is very easy to change the impeller, and more importantly inspect the output port of the water pump where impeller fins will get lodged. You cannot really see that output port well unless you remove the pump, and having SpeedSeal would not help you see this port.

I have two pumps onboard because although the Onan may be the best generator you can buy, that water pump is the worse part. In addition to frequent impeller changes (avg 250 hours), the mechanical shaft-seal will fail (leaking salt water onto the pan) and the shaft key for the impeller will fail (causing the impeller to spin on the shaft).

BTW, I never disconnect a water line or a water pump without a wet vacuum in my hand. The wet vacuum will keep salt water from getting where you do not want it, and it will also suck up debris and impeller blades...always inspect the pumped water in the wet vacuum before you dump will be surprised. You c an also use the wet vacuum to clean debris and impeller fins out of the Onan heat exchanger by removing the end-cap. Suggestion: have a new end-cap on hand (part number 130-5176 with gasket and O ring...requires 2 - 1 for each end). These end-caps are delicate and may break when removed..


BeBe 387


On Sun, Feb 15, 2015 at 4:02 PM, divanz620@... [amelyachtowners] <amelyachtowners@...> wrote:

The Sherwood G702 pump fits the Onan but its not the same construction.

The Sherwood G702 is a one piece casting, doesn't have an external plate that could be used with the Speed Seal system.
SV Elyse SM437

Posted by: "Bill & Judy Rouse" <yahoogroups@...>
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