MD6/7: How to replace water pump impellor *quickly*?

V

Vega1447

.
Oct 19, 2019
921
Albin Vega 27 Limerick
Hi all.

I have an MD6A and the water pump impellor is a Jabsco 4528-0001K

6 blade. Width: 3/4", Diameter: 1 9/16". Shaft diameter: 3/8". Drive: Slotted shaft pin.Fortunately I replaced the original water pump cover last season - with
gasket & (?) 5 tiny bronze screws - by a custom cover with O-ring and 4
knurled screws; easily turned by hand.

But securing the new impellor with the "slotted shaft pin" is still a pain.

The impellor must be seated on the Water Pump drive shaft which has a
(?) 3-4mm hole drilled through which takes a threaded pin with tiny
Allen key head to secure the impellor to the drive shaft.

This was a PITA to screw into position. I finally managed to rotate the
drive shaft to get a clear line for my equally tiny Allen key.

There "must be a better way" (TM). If I had been 10 mins of the rocks,
the rocks would have had me....

Fortunately I was on my berth...

Any suggestions?

Replace rubber/nylon impellor with bronze casting???

(BTW the old impellor was just starting to develop a crack at the base
of one of the blades so for once I seem to have got there in time.. :) )

John V1447 Breakaway
 
T

tim_klynn

.
Feb 12, 2008
337
Probably the best way to solve the problem of the poor access of the impellor is to take off the brass cover plate, remove the engine from the boat and then install a Beta Marine bz482 from Steve. On the bz482 the water pump is right on the front of the engine and easy to get to. Hopefully, others may have a less costly solution to your problem....
 
V

Vega1447

.
Oct 19, 2019
921
Albin Vega 27 Limerick
Not quite the reply I was hoping for Tim but thanks anyway... :)

John V1447 Breakaway
 
V

Vega1447

.
Oct 19, 2019
921
Albin Vega 27 Limerick
Hi Steve, OK a great reply then... :)

Yes, I have a Speedseal (couldn't remember the name).
It gets around the problem of having to undo 5 tiny bronze screw &
replace paper gasket.
A great product.

But I still have the problem of having to use a tiny Allen key to remove
and replace the almost as tiny shaft pin.

I did notice that you can just push/force the old pin out with Allen key
which is a lot quicker than unscrewing it.
Maybe I could have forced the new pin through the barrel of the impeller
rather than *slowly* screwing it in?

John V1447 Breakaway
 
D

dougpol1

.
Feb 13, 2010
528
Here is a part of an e-mail I sent to a friend about my water pump. I
had to clean it up a little for the list :) Doug
The pump is under the exhaust line right were you can only see it if you
lean just right but even then it is only partially visible. Struggled
but got the screws out of the cover plate buy prying on the back of the
screwdriver with a board against a bulkhead and turning the driver with
the other hand. Finally got the last screw out by turning the driver
with a wrench. The sun was bearing down and I had to hide my tools to
keep them from getting too hot to handle. No awning yet! I pried the
impeller out with two screw drivers hoping to get it out far enough to
get the screw out that goes through the shaft. The d^*(# thing popped
out shaft and all. There is an "O" ring between to seals and it dropped
down. Well nuts. Had to take the pump off. Held by two bolts in a
place where you can't get anything but an open end wrench on it made it
tough. Since I couldn't see the bolts I had to feel so It took 30
minutes to get the two bolts out cussing and sweating. Sweat all over my
trifocal glasses that are always out of focus. Fingers hands and knees
bleeding where I cut them on hose clamps and other assorted sharp
things. I guess it's called repair by blood transfusion. The gasket
was broken. By now the guy on the radio was saying it was 100 degrees
so I gave it up and went looking for gasket material. Couldn't find any
but was told the Napa would open at 10: am Sunday morning. My
daughter was coming to take me for a fathers day breakfast. I sat
around on the boat drinking coffee from 4:00 am till 8 am not wanting to
have to get sweatty and have to go shower again. She dropped me off at
the boat after and I worked on a couple little electrical problems and
got the running lights all working. So thats good.
Napa only had real thick gasket material and by then at 11 am the
temp was 97 and climbing. The weather man said it would likely go above
100 again. I packed it in and headed for home. There were cars broken
down on the interstate and the traffic just crept along until I had
driven a hundred miles. I was driving the little pick up with no air.
Hotter than two h__Ls.
I had, had it when I got home.
OH, by the way the impeller in the pump was in good condition. I
guess the thermostat in the engine manifold may be on the fritz. I hope
that is it because another problem could be that the engine might be
full of salt crystals since it is saltwater cooled. Hope to heck not.
Anyway with the exception of these few problems it was a nice
trip. I ate in local restaurants and didn't get diarrhea ,the truck
didn't break down, and I didn't have a sun stroke so all and all it was
a quite nice weekend.
 
T

trevy_kins

.
Oct 31, 2019
230
John, that was funny enough for publication in any sailing magazine!!
Good for the spirits. Especially to one who has been sweating just like
that for the past few months trying to get my Vega back together to
salvage what's left of the season. Keep on writing. :) Trevor -
V2915



________________________________

From: AlbinVega@yahoogroups.com [mailto:AlbinVega@yahoogroups.com] On
Behalf Of Douglas Pollard
Sent: June 23, 2010 9:31 AM
To: AlbinVega@yahoogroups.com
Subject: Re: [AlbinVega] MD6/7: How to replace water pump impellor
*quickly*?





Here is a part of an e-mail I sent to a friend about my water pump. I
had to clean it up a little for the list :) Doug

The pump is under the exhaust line right were you can only see it if you

lean just right but even then it is only partially visible. Struggled
but got the screws out of the cover plate buy prying on the back of the
screwdriver with a board against a bulkhead and turning the driver with
the other hand. Finally got the last screw out by turning the driver
with a wrench. The sun was bearing down and I had to hide my tools to
keep them from getting too hot to handle. No awning yet! I pried the
impeller out with two screw drivers hoping to get it out far enough to
get the screw out that goes through the shaft. The d^*(# thing popped
out shaft and all. There is an "O" ring between to seals and it dropped
down. Well nuts. Had to take the pump off. Held by two bolts in a
place where you can't get anything but an open end wrench on it made it
tough. Since I couldn't see the bolts I had to feel so It took 30
minutes to get the two bolts out cussing and sweating. Sweat all over my

trifocal glasses that are always out of focus. Fingers hands and knees
bleeding where I cut them on hose clamps and other assorted sharp
things. I guess it's called repair by blood transfusion. The gasket
was broken. By now the guy on the radio was saying it was 100 degrees
so I gave it up and went looking for gasket material. Couldn't find any
but was told the Napa would open at 10: am Sunday morning. My
daughter was coming to take me for a fathers day breakfast. I sat
around on the boat drinking coffee from 4:00 am till 8 am not wanting to

have to get sweatty and have to go shower again. She dropped me off at
the boat after and I worked on a couple little electrical problems and
got the running lights all working. So thats good.
Napa only had real thick gasket material and by then at 11 am the
temp was 97 and climbing. The weather man said it would likely go above
100 again. I packed it in and headed for home. There were cars broken
down on the interstate and the traffic just crept along until I had
driven a hundred miles. I was driving the little pick up with no air.
Hotter than two h__Ls.
I had, had it when I got home.
OH, by the way the impeller in the pump was in good condition. I
guess the thermostat in the engine manifold may be on the fritz. I hope
that is it because another problem could be that the engine might be
full of salt crystals since it is saltwater cooled. Hope to heck not.
Anyway with the exception of these few problems it was a nice
trip. I ate in local restaurants and didn't get diarrhea ,the truck
didn't break down, and I didn't have a sun stroke so all and all it was
a quite nice weekend.
 
V

Vega1447

.
Oct 19, 2019
921
Albin Vega 27 Limerick
Thanks Trevor but the story of the repair by blood transfusion was by
Douglas Pollard! (We never get 100 degrees F in Ireland unfortunately. :-( )
Made me laugh too... :)

John V1447 Breakaway
 
B

bobnlesafloat

.
Oct 31, 2019
163
Hi John,

On Spring Fever, I use the following method to renew the impellor:


Ensure you have a spare impellor and a cut-down 13mm open ended spanner - about 3 inches long
Close sea-cock - 10 seconds
Open cockpit floor - 60 seconds
Disconnect inlet & outlet hoses from the impellor pump - 30 seconds
Undo the two 13mm bolts holding the whole impellor pump unit to the rear of the engine block - they'll be stiff the first time, after that, it takes about 60 seconds
Remove the whole pump unit and then sit upright in the cockpit - 10 seconds
Remove front cover, replace the impellor and re-fit cover - about five minutes, but if it was desperate then I wouldn't worry about gaskets/sealant/slight water leaks and could probably do it in three.
Head back down into the rear of the engine and refit the complete pump assembly (I find it much easier to get the slot on the impellor shaft to line up as part of refitting the whole unit) 30 seconds.
Refit the two securing bolts - 90 seconds (in an emergency finger tight/60 seconds would suffice)
Reconnect hoses - 45 seconds
Re-open seacock & start the engine - 15 seconds.
The foregoing pre-supposes that you know where the spare impellor is - a couple of years ago we met a couple on a 45 foot Amel, who were tentatively anchored for nearly nine hours before they discovered where they'd stowed the spare impellors.
 
T

trevy_kins

.
Oct 31, 2019
230
Hmmm. . . sorry Doug . . . . maybe I need new trifocals too. Trevor
V2915 Mystic Rose



________________________________

From: AlbinVega@yahoogroups.com [mailto:AlbinVega@yahoogroups.com] On
Behalf Of John A. Kinsella
Sent: June 23, 2010 12:45 PM
To: AlbinVega@yahoogroups.com
Subject: Re: [AlbinVega] MD6/7: How to replace water pump impellor
*quickly*?





Thanks Trevor but the story of the repair by blood transfusion was by
Douglas Pollard! (We never get 100 degrees F in Ireland unfortunately.
:-( )
Made me laugh too... :)

John V1447 Breakaway
 
T

trevy_kins

.
Oct 31, 2019
230
Hmmm. . . sorry Doug . . . . maybe I need new trifocals too. Trevor
V2915 Mystic Rose



________________________________

From: AlbinVega@yahoogroups.com [mailto:AlbinVega@yahoogroups.com] On
Behalf Of John A. Kinsella
Sent: June 23, 2010 12:45 PM
To: AlbinVega@yahoogroups.com
Subject: Re: [AlbinVega] MD6/7: How to replace water pump impellor
*quickly*?





Thanks Trevor but the story of the repair by blood transfusion was by
Douglas Pollard! (We never get 100 degrees F in Ireland unfortunately.
:-( )
Made me laugh too... :)

John V1447 Breakaway
 
V

vegasailor2001

.
May 3, 2004
34
Hi!

I am not sure I really understand the proplem, but this is the way I change my impeller:

1. Remove the lid. Normally the trickiest part since I still have the the orginal lid with tiny screws, but manageble with som small screwdrivers.

2. Use two small flat pliers and carefully grabing the wings of the impeller and pull it out.

3. Inspecting the impeller and if needed, change it. I normally change it every second year, needed or not. It is very easy since you have it removed!

4. Put on vaseline on the new impeller and try to put it back oriented the same way the old impeller was.

5. Put on a new gasket and put on the lid.

It takes about 20 minutes if, like someone pointed out, you remember where the new impeller and especially the new gasket, is located.

Yours,

Björn
Vega 2757
 
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