Yanmar 2gm raw water impeller removal?

pateco

.
Aug 12, 2014
2,207
Hunter 31 (1983) Pompano Beach FL
Last Wednesday, I got a temp alarm on our way out for evening races. I looked off the stern, and saw no water pumping. Shut down, and went below to check. Pump would spin, but no water. Luckily I keep a spare pump with fresh impeller in the parts box. I quickly changed out the pump, (just two 1/2" bolts) and was able to make it to the race start on time.

This morning, I took the dead pump home and opened it
. 2017-07-22 13.39.00.jpg
Impeller was torn and all bunched up on one side.
2017-07-22 13.45.11.jpg
I was able to pry it out.
2017-07-22 13.46.20.jpg
But the central collar seems to be seized to the shaft.
2017-07-22 13.50.53.jpg
How can I remove this with out messing up the shaft or the bearing in the pump? Prying and needle nose pliers have not worked.
 
Nov 6, 2006
9,885
Hunter 34 Mandeville Louisiana
One way to address would be to take off the circlip that holds the bearings in the housing.. Support the body on the mounting ears.. then tap the shaft out the (pulley) end using a large flat faced punch (or a bolt) that is slightly smaller than the ID of the impeller hub that is seized on. .. you'll want to have a new seal and bearings and impeller and gasket on hand .. then it'll be rebuilt and ready. attached is the pump drawing...
If it is a 2 GMF the bearings are 6202.. if a 2GM (no heat exchanger) the bearings are 6200 on the original pumps. Read the numbers on the bearings to be sure.. they are inexpensive.. A good bearing supply plce should have them for 6-10$ each.. the seal should be about $6..
 

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Jan 7, 2011
4,727
Oday 322 East Chicago, IN
Penetrating oil would help, let it sit for a while. Then maybe some pointy locking pliers to get a good grip on what's left of the impeller.

Be careful of prying against the pump body with a screw driver....don't ask me how I know

Greg
 

pateco

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Aug 12, 2014
2,207
Hunter 31 (1983) Pompano Beach FL
PB blaster overnight worked. Thanks guys. New impeller should be here Tuesday.
2017-07-22 14.11.39.jpg
 
Apr 14, 2010
195
Jeanneau 42DS Larnaca Marina
You are very lucky that you carried a spare pump. Most of us carry spare impellers....
 
May 24, 2004
7,129
CC 30 South Florida
Just a thought, when an impeller comes apart like that there is a fair chance that small pieces can work their way into the cooling passages of the exchanger and cause immediate or future blockages. Just inspect the torn impeller and gauge whether it is all there or there might be pieces missing and how large could they be.
 
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pateco

.
Aug 12, 2014
2,207
Hunter 31 (1983) Pompano Beach FL
You did order TWO, didn't you?
Fresh one in the replacement pump, and once this one rebuilt, I will have another spare. I guess I could order another impeller kit so I don't have to wait shipping time without a spare next time, But I have a good used one (still supple and no cracks) in the parts kit from my last annual replacement just for emergencies.

You are very lucky that you carried a spare pump. Most of us carry spare impellers....
I can give thanks to the previous owner for the spare pump. Trying to replace the Impeller at inopportune times can be a real pain.

I did the impeller replacement the first time we had a failure by dropping sails and anchoring near the inlet to our home port and then trying not to lose any of the cover screws while bobbing around in seas and 100° Heat. Two weeks later I found the spare pump in one of the lockers in an unmarked cardboard box along with some spare V belts. The pump swap is much easier, and takes a lot less time than replacing the impeller. LOL

Just a thought, when an impeller comes apart like that there is a fair chance that small pieces can work their way into the cooling passages of the exchanger and cause immediate or future blockages. Just inspect the torn impeller and gauge whether it is all there or there might be pieces missing and how large could they be.
This is a standard 2GM (Raw water cooled) so no exchanger to worry about. But from taking it apart, it looked to be all there Just destroyed.
 
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pateco

.
Aug 12, 2014
2,207
Hunter 31 (1983) Pompano Beach FL
One way to address would be to take off the circlip that holds the bearings in the housing.. Support the body on the mounting ears.. then tap the shaft out the (pulley) end using a large flat faced punch (or a bolt) that is slightly smaller than the ID of the impeller hub that is seized on. .. you'll want to have a new seal and bearings and impeller and gasket on hand .. then it'll be rebuilt and ready. attached is the pump drawing...
If it is a 2 GMF the bearings are 6202.. if a 2GM (no heat exchanger) the bearings are 6200 on the original pumps. Read the numbers on the bearings to be sure.. they are inexpensive.. A good bearing supply plce should have them for 6-10$ each.. the seal should be about $6..
Any idea where to get a spare shaft or pulley? The shaft in the spare pump seems to be very slightly off at the end where it attaches to the pulley. Either that or the pulley is a little bent. It spins fine and doesn't vibrate, but it is enough off that I am worried about possible belt wear . Once the original is repaired this one will go back in the spares box, but having it perfect would ease my mind.
 
Jul 27, 2017
1
Hunter 30T Ft. Myers Beach, Fl
Just for reference, I recently had to replace the raw water pump on my 91' 2GM20f and found I could spend $200 less by ordering the Johnson pump vs the identical pump in a Yanmar package. The pump was identical in every respect and bolted on with no modifications. I figured it's worth sharing.
Screenshot_20170727-175526.png
 
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pateco

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Aug 12, 2014
2,207
Hunter 31 (1983) Pompano Beach FL
Water pump refurbishment completed. Going back on the boat tonight.
2017-07-31 08.21.25.jpg 2017-07-31 08.21.51.jpg
 
Jun 1, 2007
265
O'Day 322 Mt.Sinai
Just for reference, I recently had to replace the raw water pump on my 91' 2GM20f and found I could spend $200 less by ordering the Johnson pump vs the identical pump in a Yanmar package. The pump was identical in every respect and bolted on with no modifications. I figured it's worth sharing.View attachment 139287
Where'd you have that price of $400+ ? I see Toad has it for $245. I think I'd like to get a spare myself..

http://shop.toadmarinesupply.com/ships_store/?p=details&mfc=Yanmar&sku=128397-42500
 

pateco

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Aug 12, 2014
2,207
Hunter 31 (1983) Pompano Beach FL
Two weekends ago, after I had just finished up doing a fuel filter change, and restarted the motor, I noticed I had no water flowing out my exhaust. I stopped the engine and spent 10 minutes swapping it out for my spare water pump. This solved the cooling issue, but left me with a pump to overhaul. When I took it apart, I noticed two issues, both requiring new parts.
  1. Impeller (only about 6 months old) lost a fin, and the fin had jammed itself into the water outlet.
  2. Jammed impeller somehow managed to strip the keyway cuts in my pump pulley, allowing it to spin under load.
2018-06-10 11.49.04.jpg

2018-06-10 11.49.12.jpg

So I picked up a new impeller locally, and ordered the pulley from Toads. Got it put back together and it is now in the spares box.

This is the second pulley that I have had to replace for this very reason, so now both of my pumps have brand new ones. Have any of you had similar issues with the pulleys?

How long do your impellers last?
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
FWIW. I installed a SpeedSeal Life a couple years ago. I think they re-named it to "Easy Slider'.
The premise may be, if it's easier to replace the impeller, it will get done more often. Also nice in a failure if you don't have the proper tools handy.
Not going to help if your shaft locks up.
 

Sailm8

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Feb 21, 2008
1,746
Hunter 29.5 Punta Gorda
You might consider replacing the shaft and bushing. Maybe some wobble might be jamming the shaft and damaging the pulley.
 

pateco

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Aug 12, 2014
2,207
Hunter 31 (1983) Pompano Beach FL
You might consider replacing the shaft and bushing. Maybe some wobble might be jamming the shaft and damaging the pulley.
If I replace the shaft, that means new bearings and seals as well. I found the shafts at Toads, and a Yanmar bearing and seal kit on E-bay. However I think I will wait and see how well the new pulley works on the spare pump I have installed now.
 

HMT2

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Mar 20, 2014
899
Hunter 31 828 Shoreacres, TX
Chip,

I’ve had my boat almost eight years and have never had a single issue with my water pump, (saying this in writing could be the kiss of death to that good fortune) I have replaced the impeller maybe three or four times. But they were always in great shape. That you have had so many issues would make me think something is not quite right. Good luck!