Yanmar Water Pump rebuild

[Warren Milberg]

Anyone have step-by-step instructions for replacing the seals in a Yanmar 2GM20f water pump. Mine has begun to leak a bit and I assume it needs new seals. I have the diagram for the water pump, but am looking for instructions for how to remove/replace the seals.

 

[Sailm8]

I just used a vise and the appropriate sized socket as a tool to press the seals in and out. Extremely easy once I found someone with a vise.

 

[Stu Jackson]

Here's how we did ours. Maine Sail also has a writeup for a Johnson pump on his website and most likely in his Musings, too.

http://c34.org/bbs/index.php/topic,6766.0.html

There are a couple of links in that which you should read, too.

 

[njsail]

This might not be written instructions but many years ago I did a photo essay of each of the steps. Of course it doesn't show banging the shaft out (that was fun...not). It seems to still be here at this URL. Before buying a full rebuild kit which turned out to be useless to me try replacing the shaft seal for about $10. If not just buy the new water pump (my opinion). Good luck.

http://ipphotos.com/view_ad.asp?Ad_ID=586

 

[RichH]

I suggest you get the Yanmar tech manual specific for your engine series and follow it, as there are precise tolerances/clearances between the bearings and seals for most Yanmar pumps. If you dont follow these specs. a rebuilt will be 'wasteful' in both time and $$$.

 

[Ray Bowles]

Dress the seal riding area on the shaft with crocus cloth before installing the new seal. This removes burrs and stuck on debris from this area.
Ray

 

[onecoolair]

Anyone have step-by-step instructions for replacing the seals in a Yanmar 2GM20f water pump. Mine has begun to leak a bit and I assume it needs new seals. I have the diagram for the water pump, but am looking for instructions for how to remove/replace the seals.

Here are some pictures of my pump that I had to service just this past summer. BTW..Lessons learned don't ignore that small drip. So just as you clear the marina entrance you have a total failure.
The spring in the rubber ring seal needed tightening just a bit. Was able to get the rubber "o" ring in and over the spring ( or was it under ??)to increase the seal tighteness to the shaft. I figured this out after I had just bought a new one. Its still working so the new one is just saved as spare for now. I hope the pictures help. It really was not that hard to fix.

 

[Scott B]

Warren, I have the Service manual for the YM Series. Assembly instructions are very detailed.... they essentially tell you to put it back together.

When replacing the oil seal, coat the oil seal with grease and insert.
Moun the pump shaft, ball bearing and v-pulley to the pump unit and fit the bearing retaining ring.
Coat the shaft with grease.
Mount the impeller.
Mount the O-ring and the cover.

Only spec's given are flow rates and clearance for the fresh water impeller to the housing.

Disassembly are even shorter..... take it apart.

Stu and Maine Sail have much more detailed info above.

 

[Ken13559]

I have written instruction for own reference. Hope it makes sense to you. Attached herewith.
Oops! Cannot upload Word doc. Need to convert to pdf first. Later.