Hi Nonsuchers
I have gone 3 years now without changing out my raw water impeller - mainly because it has been so cumbersome to do this. In past, I used to take off the alternator to remove the raw water pump, so as to have easy access to removing the cover plate to change out the impeller on my workshop bench. This year, I found that that one of the 4 nuts securing the pump housing to the engine block was rusted and eroded to the point that I could not get it off. It is a blind manoeuver and very tricky to do even when the nuts and threaded rods were in clean condition.
I am now considering removing the engine, so I can get at that bolt to remove the raw water pump, and then having a machine shop build a conversion so that the raw water pump/impeller cover is more accessible. One idea is to machine a coupling so that the impeller cover is rotated 90 degrees so it faces to port, and could then be easily accessed through the engine room hatch in the port quarter berth.
Has anybody done such a conversion - otherwise - how the heck would you change out an impeller at sea if necessary - given the limited access?
To replace the impeller in my boat a circlip on the pump shaft needs to be removed before extracting the impeller - this is next to impossible to do with the way the pump is installed and with access impeded by things like the starter motor which is just aft of the impeller pump cover.
I am now very concerned about an impeller failure that I would not be able to repair and replace at sea.
Thanks to you all for any info and shared experiences.
Speed Seal certainly made access much better on my 30U Westerbeke 27A.
I don’t know whether there are additional access problems on a 22, Greg sure made the job sound like it is difficult, but I can’t imagine that Speed Seal wouldn’t help. It has also been improved in recent years.
Fred Rachwitz
Concerto, NS 30 U 445
Harbor Springs, MI
Northern Lake Michigan
Ahh yes the Water Impeller change. Another one of those maintenance items I no longer have to deal with since converting to electric propulsion on my Nonsuch 30. You might want to consider what I did before I got rid of the Westerbeke engine all together. Which is to put on a Speed Seal cover. Be aware it may require you to purchase a new version of the water pump since the covers are not made for the original water pump on my Nonsuch. You can keep your current pump as a spare. It seems to be the way to go on the Nonsuch if you have a Westerbeke and want an easier time of changing the water pump. I too use to go several years before changing the impeller. But, I had a yikes moment when I got around to finally installing the Speeb Seal cover: THE BIANKA LOG BLOG: Lessons learned: The raw water impeller.
THE BIANKA LOG BLOG: Lessons learned: The raw wate…
I decided while I was waiting for parts to repair the engine I would tackle another item on the maintenance list. It was something I had been putting off for a few …
lookup speed seal. company in England makes replacement cover with large finger knobs to remove cover.
John Iscaro
SV / PHUNSUCH NS26U
Vice Commodore / Halloween Yacht Club
Stamford CT
I’ve got the pump removal time down to about 20 minutes. Replacing it is about 25. I do it every couple of years but if I use one of those blue impellers, I may go every 4 or 5. However, I do flush my system every year when I haul for a month in January.
Joe Valinoti
S/V IL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
You only haul out for January ???
I hauled Sept 15 this year, and plan to launch June 15 next year.
Different up North eh?
But…I DO live aboard all summer, so I get 90 full days of use.
The Blue Systems one lasts an awful long time and don’t go bad if run dry. I don’t have to haul, but because I have the hull scrubbed prior to every race, and use ablative paint, I need to replace that coat. In addition, I like to dry the hull for a month. Don’t want to rub it in, but we sail all year in eastern NC.
Joe Valinoti
S/V IL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
There are apparently 2 pumps that Westerbeke sold for that engine. The original one that you describe and the new one that is a Sherwood pump.
The main difference is that instead of the stupid circlip and half moon key to hold the impeller in place there is a pin that crosses a slot on the impeller shaft. As well there are 5 blades vs I think 8 and the “Speedseal” is available for the new pump.
The new one is easier to change, however on a hot engine I doubt I would want to try it. I need to remove the hoses to get access and I do it from the quarter berth. Takes about 15 minutes.
As far as the old pump is concerned. It is easier to remove the entire pump than change the impeller. I had to remove the alternator to change the impeller and it was at least a 3 hour job.
The frozen bolt is not good news. You may want to check the oil pan below if the problem is salt water exposure. I have had good luck removing rusted fasteners on my MG using a product that is a freezing / penetrating oil. It uses a gas to freeze the fastener which when it returns to room temp causes enough expansion to break the hold of the rust. It is the reverse of using a torch, but not as much fun :).
As far as the blue impellers are concerned, have a friend who loves them, Joe has had good luck as have others. On my engine they have been an epic fail. The will not prime the line after sailing in any kind of wave action. After two adventures like this we went back to the old black ones. You can find Sherwood impellers for this new model pump for about $25.
Actually, my last experience with the blue impeller was not good. Some of those impellers although spec’d for certain W-27 pumps actually did not fit correctly. I finally got the manufacturer to change their listing.
Joe Valinoti
S/V IL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
