CAT 3208N issues

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robs523

Senior Member
Joined
Dec 24, 2014
Messages
103
Location
USA
Vessel Name
Magnetic North
Vessel Make
1985 Californian 34
Hello, I just bought a Californian 34 with twin CAT 3208N engines. During sea trial and survey, there weren't any leaks noticed. The day I took ownership, I found a leak on the port motor that looks like it's coming from the fuel pump or possibly throttle lever. The engine runs great and sounds good, not like it's sucking air. Does anyone have any suggestions on where to start? I like doing stuff myself, but I'm a little nervous to do something I can't undo and be docked til someone can fix it. I've tinkered around a lot but only on gas-powered land vehicles, not diesels or boats. I read that the fuel pump needs timed if taken off, which sounds complicated. Especially with the limited space in the engine room. Any suggestions are welcome and appreciated.

Also...today when I accelerated towards WOT to see how she would do, we got a lot of smoke. During the sea trial, we did the same thing and there wasn't any smoke, and it was something the surveyor and owner both commented on as being a good thing. Is this a concern, and if so, how worried should I be?

The CAT dealer in Juneau has two mechanics here a few weeks that will probably be able to look at it before they leave, but at $150/hr I'd like to limit the hours if I can. And why did this only show up after I bought it!!! (I'm not really looking for answers on that one) Thanks!
 
You did not say what is leaking? Fuel, coolant or raw water? I'm guessing since you are saying looks like it's coming from the throttle shaft and mentioned fuel pump then fuel?

If the throttle shaft is leaking fuel you will see pink color in the valley between the heads. If that's the case then the injector pump will have to be removed to access it. Most shops will not put a pump that just needs a repair on their equipment for testing. So most likely they will insist on a rebuild first. Depending on how many hours you have on the engine that would most likely be a good thing.

To remove the injector pump the engine crank shaft has to be rotated to top dead center. There is a place on the front where a pin is inserted to "time" or to be sure the injection pump gears are aligned in the proper position. It then takes a special tool to remove the gear from the pump once the pump Is un-bolted from the engine and all the fuel lines are removed.
 
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Wipe up the area and find out exactly where the fuel is coming from. If the throttle shaft seal, that housing can be removed from the injection pump without removing the whole pump and disturbing the timing.
 
Agree with Ski in NC. Check the small o ring on the throttle shaft. Also check the clamps that hold the injector lines, sometimes vibration will wear a hole in the line. Great engines!
 
thanks for the replies.

Yes, Capt Jon, it's fuel. Sorry that wasn't clear.

There is fuel in the valley, but it doesn't look pink, more clearish/yellow like straight diesel. The problem is that I can't tell where it's leaking from. Anything I can see or feel is dry. I have tried a mirror unsuccessfully so far. They have 1600 hours since rebuilt in 2004.

Does the smoke matter? Or are these like diesels on a truck that smoke almost anytime you floor it?
 
Marine fuel that does not have a highway tax included has red dye in it. Your fuel may not have red dye.
I use paper towels to search for leaks. Clean up the area as best you can, then wrap paper towels around parts that are suspect. Wrap fuel lines, seals, anywhere that you can get to that might be the leak. Then after running the engine for a few hours the towels might show the source if they are stained with fuel.
 
They must not Dye diesel fuel in Alaska. Anyway you can lay an oil mat down in the valley and slide it under the pump. Clean the valley first so you start out fresh. This will help you track the leak down. A throttle seal is something that can, and does leak on these engines. Also like tingum said look for leaking around the fuel line nuts. Also rust is a big enemy of these engines. Make sure the lines themselves are not leaking.

As for the black smoke, 3208's can smoke somewhat. However it should not be black heavy smoke. A slight grayish color is the exhaust cloud is ok. If it's black then there could be many other issues. Anything from a dirty bottom or running gear to the fuel system itself. Ski is a great person to ask more in depth questions of.
 
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