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  Topic Review (Newest First)
08-14-2012 08:20 AM
Re: Diesel Engine trouble-shooting

I used a fuel polishing and tank cleaning service this past Spring. The fuel is run through filters and then discharged under pressure back into the tank where it dislodges the accumulated solids in the tank, which are then withdrawn out of the tank and into the filters. This was done continuously for nearly three hours.

It should result in clean fuel and a clean tank (and a lighter wallet).
08-14-2012 01:11 AM
Re: Diesel Engine trouble-shooting


You may want to check and see if your fuel pick-up tube has a screen filter attached at the bottom -- some do, and they invariably cause problems. If there's a screen there, I'd take it off.
08-13-2012 11:12 PM
Re: Diesel Engine trouble-shooting

Originally Posted by davidpm View Post
There are fuel polishing services. they pump your fuel through a series of filters to make sure it is clean.
I imagine that will cost more than the 10 or 20L of fuel actually in the tank. But the problem is what's in the tank... I imagine, and I have to use my imagination since I can't see in there, it has some rust and debris that needs to be washed, cleaned out and then repaired or it will continue to rust.
08-13-2012 08:23 PM
Re: Diesel Engine trouble-shooting

There are fuel polishing services. they pump your fuel through a series of filters to make sure it is clean.
08-13-2012 08:22 PM
Re: Diesel Engine trouble-shooting

maybe you have two things going on. Wouldn't be the first time.
A charge problem and a fuel problem.
08-13-2012 03:49 PM
Re: Diesel Engine trouble-shooting

It appears that there was a half-teaspoon of water in the fuel filter cup, which I emptied. At first, I thought this may have gotten shaken up and pushed into the engine. However, when I reattached the fuel filter I had no success bleeding the fuel line. I detached the fuel filter intake and tried to start the syphon. Sucking on the hose was unusually difficult and the syphon, once started, wouldn't continue. I suspected a clogged intake so I blew as hard as I could through the line a few times and that seemed to loosen everything up.

The syphon runs cleanly now and the engine has been running for 20 minutes and sounds good.

So the problem is likely a clogged intake, but since I only temporarily unclogged it... uhm... how the heck am I going to clean the tank?! The closest thing to an inspection hatch is the fuel filler hose attachment which is barely big enough to see in, let alone reach in to clean.

What methods are there for cleaning out an old diesel tank? I don't think I should take my buddy's suggestion of a hose and dish detergent... ;-)

Maybe I'll call a mechanic to price a new plastic tank.
08-13-2012 01:34 PM
Re: Diesel Engine trouble-shooting

More info...
I'm on the boat as I type this...
After using the battery for radio and wind instruments on a 10hr trip without recharging, and sitting for a week, the battery still reads 12.15V.

I start the engine and leave it at idle. The battery now reads 12.4V.
I rev the engine under load (tied to dock, half-throttle). The battery now reads 12.4V. I expected more...
I rev the engine under load (tied to dock, full-throttle). The battery now reads 13.9V. This is what I expected.

The engine still seems to be labouring.

I have verified the impeller still looks pristine (only about 6hours on it).
I have verified that I am evacuating water from the exhaust.
I have verified that the oil is topped up and doesn't appear to have dropped at all since the oil change (about 6 engine hours ago).

I will be checking the fuel & fuel filter shortly.

The green light is still flicking on my panel... I'm pretty sure that's the charge light, not temperature. I've been given some advice on how to check the stator but I'm still lost. Any further advice would be welcome.
08-12-2012 01:31 PM
Re: Diesel Engine trouble-shooting

Thanks davidpm. Yes, air getting in definitely crossed my mind (I had this problem last year) but I forgot to jot it down. Any advice for how to determine where air is getting in?
Last year, it was the crush washers around the... lift pump... (I think I have that term correct).

While I was going through the chop exiting the channel, heeled to starboard (tank on starboard) I thought it might have sloshed the 1/2 tank of fuel enough such that it got a mouthful of air. But later on, it also slogged down a bit which is strange as the lake was dead calm and we were upright.

Originally Posted by kd3pc
the lights are a result of the engine stalling, not the other way around....
kd3pc, I know what you are thinking here, but I'm not quite that clueless. ;-) Yes, the lights pop on when the engine stalls and that may have been the case on the first stall. However, when we arrived at home, the engine was running with the green light flickering. Not both lights, not solid and the engine was running for several minutes while this was occurring. The latter case was definitely not a result of a stall.

Hopefully I can find time today to get to the boat and figure out where that green light is attached.
08-12-2012 07:53 AM
Re: Diesel Engine trouble-shooting

I would check the fuel pickup tube as well, as she quit while in motion....

the lights are a result of the engine stalling, not the other way around....

the engine needs air, steady clean fuel, and enough revolutions to compress the fuel to fire...

even after 40 years, I always check upon startup to see that the engine is shipping water...and often while running...
08-12-2012 06:23 AM
Re: Diesel Engine trouble-shooting

I second the thought about air getting in the lines or perhaps a clogged filter. If you've checked the impeller and found it to be ok, it probably is not overheating. Besides, I had the impression from your description that the engine had not run a long time before dying. So, I think fuel delivery problem; air in lines or dirty, clogged filter.

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