Over the past few weeks I've been doing my "spring maintenance". Yeah.. I'm late due to a little foot problem that set me back. I also have the pleasure of putting my 17-year old son to work in the engine room as he is home from school:
One of the items I decided to do this year was put some new fuel coolers on the engines. The guy that runs sbmar.com (and does a lot with boatdiesel.com but I'm not sure if he owns it or not) had some new QSM11 fuel coolers that were pulled off a couple of new engine installs and replaced with something else. So they were technically "used" but never used. New ones are about $1000 and he sold these to me for about $350 a piece. The port side fuel cooler on my boat did not have new zincs put in it for the first year of it's life (that's another story) so I've always worried about that one. Having sea water get into the fuel system just seems like an expensive thing to deal with and this seemed like cheap insurance.
The other thing with regards to the location of these coolers is they are before the raw water pump and first in line after the strainer on the raw water circuit. When the engines are flushed, these things are not flushed if you follow the directions in the QSM11 manual. Being in line right after the strainer, one has to wonder what accumulates in there. Here's a shot of a new one installed on the starboard engine. It is in the lower right corner of the picture below the oil fill:
Yeah.. I know.. I have a pesky oil leak under that raw water pump I've been chasing... It is either coming from the gasket on the water pump or from a bolt in the oil pan.
You can see from the picture that these things are not easy to get to. They are tucked under the starter on one end and tied into the water pump and the stringer is tight against it on one side and the oil pan on the other. Doing this on the port engine is a royal pain in the ass and requires removal of part of the exhaust. Here's a shot of the bruising on my arm working these things:
My son actually did most of the work on the port engine and did a great job. Here's one of them removed:
And... here's the stuff... This is looking in the end that receives water from the strainer:
Holy crap!! I'm surprised the engine was getting ANY water flow. The engine temp was running at its usual 163 when I last used the boat in Jan. but that thing sure looks blocked. This is looking into the end where the water leaves:
The scale build up is pretty bad and it was time for these babies to come off and be cleaned at least. These are five years old...
Note that I put a zinc on the end that water leaves the fuel cooler. I thought that since there were plugs on each end that a zinc would go in each end. I don't think that is the case though. I believe, in looking at the parts manual, you are only supposed to put a zinc in the end where water enters. If the zinc breaks off the water exit point, it will go right into the impeller on the water pump and destroy it. If it is only on the entry point of the cooler and breaks off, it can't get to the impeller. That's probably why I go through more impellers than I should... I think that opening on the exit end is to tap into for dripless seals or something else... My dripless water source ties into the gear cooler which is the same thing which is why I think this.
I'm going to clean the starboard one up that is pictured here and pressure test it and keep it as a spare. The port side one, I don't have a picture, actually was developing a diesel fuel leak at the base of the fuel fitting where it was welded.
I think I timed this before it became a bigger problem...
Just an FYI post.
One of the items I decided to do this year was put some new fuel coolers on the engines. The guy that runs sbmar.com (and does a lot with boatdiesel.com but I'm not sure if he owns it or not) had some new QSM11 fuel coolers that were pulled off a couple of new engine installs and replaced with something else. So they were technically "used" but never used. New ones are about $1000 and he sold these to me for about $350 a piece. The port side fuel cooler on my boat did not have new zincs put in it for the first year of it's life (that's another story) so I've always worried about that one. Having sea water get into the fuel system just seems like an expensive thing to deal with and this seemed like cheap insurance.
The other thing with regards to the location of these coolers is they are before the raw water pump and first in line after the strainer on the raw water circuit. When the engines are flushed, these things are not flushed if you follow the directions in the QSM11 manual. Being in line right after the strainer, one has to wonder what accumulates in there. Here's a shot of a new one installed on the starboard engine. It is in the lower right corner of the picture below the oil fill:
Yeah.. I know.. I have a pesky oil leak under that raw water pump I've been chasing... It is either coming from the gasket on the water pump or from a bolt in the oil pan.
You can see from the picture that these things are not easy to get to. They are tucked under the starter on one end and tied into the water pump and the stringer is tight against it on one side and the oil pan on the other. Doing this on the port engine is a royal pain in the ass and requires removal of part of the exhaust. Here's a shot of the bruising on my arm working these things:
My son actually did most of the work on the port engine and did a great job. Here's one of them removed:
And... here's the stuff... This is looking in the end that receives water from the strainer:
Holy crap!! I'm surprised the engine was getting ANY water flow. The engine temp was running at its usual 163 when I last used the boat in Jan. but that thing sure looks blocked. This is looking into the end where the water leaves:
The scale build up is pretty bad and it was time for these babies to come off and be cleaned at least. These are five years old...
Note that I put a zinc on the end that water leaves the fuel cooler. I thought that since there were plugs on each end that a zinc would go in each end. I don't think that is the case though. I believe, in looking at the parts manual, you are only supposed to put a zinc in the end where water enters. If the zinc breaks off the water exit point, it will go right into the impeller on the water pump and destroy it. If it is only on the entry point of the cooler and breaks off, it can't get to the impeller. That's probably why I go through more impellers than I should... I think that opening on the exit end is to tap into for dripless seals or something else... My dripless water source ties into the gear cooler which is the same thing which is why I think this.
I'm going to clean the starboard one up that is pictured here and pressure test it and keep it as a spare. The port side one, I don't have a picture, actually was developing a diesel fuel leak at the base of the fuel fitting where it was welded.
I think I timed this before it became a bigger problem...
Just an FYI post.
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