Maintaining My Boat: How a Starter Repair Created an Opportunity
April 9th, 2013
Boat Maintenance

Warning: This post has nothing to do with marine electronics. Instead, the subject relates to taking advantage of a repair opportunity to improve my general systems. This post describes an opportunity to move my water pump to a better location, even though the starter was the original issue.

As boaters, we all have those ordeals maintaining out boats. It takes work but the joys of sailing are so worth it!

A couple weeks ago my family and I decided to take the boat out for a spin on a sunny Sunday afternoon here in the Pacific Northwest. It was an early spring trip and not all my maintenance had been done to get her ready for cruising season.

The diesel started quickly and we motored out of the slip when we noticed an electrical burning smell and some smoke coming from the engine cavity.

I quickly shut the engine down and turned off my battery switches. A boat fire, even on Lake Union, can quickly turn into a serious deal. I suspected a corroded lug end might be the culprit. My boat is old and she has been on a budget for a long time. The engine is a pretty new Yanmar that rebuilt and installed myself in 2007 and I have lots of faith in the engine. The battery lugs I did in 2001 with less than stellar tools and I’ve had my reservations about their quality.

With the engine and batteries off, we still had a delightful sail on Lake Union and we did not have to break out any fire extinguishers. We tried the engine at the end of the sail but it would not start and made more smoke. I felt relieved that it was not a difficult sail back into the slip. However, something needed addressing before we could use the boat again.

A couple days later I got a chance to take a look and try to figure out what had failed. The main lug to my starter looked like it got a little hot but I quickly figured out that was because my starter had melted and dropped a ball of ooze on the stringer underneath it. I needed a new starter motor and of course it is located in a hard place to work on the boat. In fact I rarely inspect that side of the engine and it was obvious that the rear seal on my waterpump had been spraying some water on that side of the engine too. It was still late winter and I figured that it was time to address all these issues at once before spring.

The engine on Distance is a Yanmar 3JH series engine. It's a modern engine that was designed to go in modern sailboats with access to all sides. Also, a small footprint size to the engine is an important selling point since accommodation around the engine can be maximized. I think these two forces caused Yanmar to mount this engine’s raw water pump in between the starter motor and the alternator.

Removing the water pump to service it would mean that the forward/port engine mount must first be removed. I saw many reasons not to put the pump back in this location. Moving the water pump was worth the effort.

yammar engine

Yanmar 3JH in her spot on my boat Distance

water pump access

View of the front waterpump access. The corrosion on the alternator was caused by a leaky rear seal on the pump.

standing on head

Fun times standing on my head for rear access to the pump and starter motor.

From the outside the 3JH looks to have a couple of possibilities for relocation. The first option would be to mount the pump on the front side of the power take-off where it was originally mounted. Some issues: the alternator belt was in the way and there is a bearing race cast and machined into the engine that would have to be removed. I decided that was too big of a job.

original water pump

Original water pump with rusty engine mount in the way

inside power take off

The inside of the power take-off once the pump was removed.

The second option would be to mount the pump to the PTO mounted to the front of the injection pump cam. The problem with this was there were no splines to attach the pump to on the front of the cam. I found an adapter for it online but I would have to remove the front cover of the engine to install it.

The third option was the easiest and the one I went with. This was to purchase a new waterpump and install it on the main crank of the engine. The original pump with the engine is a Johnson Pumps F5B-9. However, it is a special Yanmar version of this pump that costs around $600 to replace. Instead I purchase a Johnson Pumps F5B-9 that was intended to bolt to the crankshaft of a Chevy 350. It was about $175 to purchase. It has a bolt patter close enough to the bolt pattern on my Yanmar’s crank that I was able to bolt it up without modification. I needed to build a bracket to keep it from spinning. I built it out of aluminum that I heated and bent and drilled to bolt on the front of the engine. That was the most technical part of moving the pump.

The water pump is in and tested and all seems to work fine. Now all of the engine’s electrical pieces are isolated from a water pump leak, while the pump is now easily accessible for future service. I saved money on replacement if I had tried to replace the failing old pump. There are other headaches like I have to move a battery bank that was once located where the new pump went, but all in all I think this move is worth it and it will give me lots of peace of mind when cruising with my family this summer.

final new waterpump

Finally done! The new raw water pump attached to the crank with its bracket to prevent it from spinning.

The other two options for pump placement are visible as well. They are the upper left where the aluminum plate is mounted with four bolts, and below the alternator on the right. The belt and other issues kept me from using that area.