5411 won't start... continued

[jakez]

I posted regarding this problem some time ago, and got a lot of good advice from many of you. I wanted to post an update with what I've done, and where it's at both so it's archived on this forum and for some help.
A quick recap: My 5411, which has run and started well until now, suddenly wouldn't start. I've replaced my cranking battery (with a 650 amp), I've rewired the ignition, putting in a new wiring harness, running a heavy gauge wire directly from the alternator to the starter, replaced the ammeter with a voltmeter, etc. I replaced the alternator. I pulled the glow plugs, they tested well. I cleaned all the electrical connectors associated with the engine / ignition system. I replaced the fuel filters. I've bled the line and get good flow.
With all that done, the engine cranks faster - I definitely have more ignition power, but it still doesn't want to start. I finally got it running today - It sounded like it was getting really close to starting so I kept the starter motor going longer than I would have and it finally took. I ran it for about 10 minutes, throttled up, down, etc. Seemed to run fine. When I put the throttle back at 12 o'clock (normal idle), it died and I couldn't get it going again. I haven't pulled the injectors, or pulled off the manifold to take a look at the valves. Before I invest more money and time, I thought I'd see if anyone has any ideas or similar experiences.

 

[Stu Jackson]

Wow, great description and nice work. Congratulations.

Here's what I'd do if it was my engine: Check the stop assembly which is most likely starboard forward end of the engine. There are two springs in there, look at the parts on the Torrenson website or a parts manual on our C34 website.

Good luck.

 

[jrowan]

Jake, I'm sure a commented before since I also have a 5411.
Your engine problem sounds like its not getting enough fuel.
You said you checked the fuel lines, but did you actually pull out the fuel pipe in the top of the fuel tank? I had a problem like yours on my last boat's motor, a Yanmar, & found that there was wire mesh screening pushed in the inside end of the fuel tank pipe to act as a pre-filter. In reality it acted like a pre clogging device & starved the motor for fuel. There is also a small mesh screen located on the intake side of the fuel pump at the engine that can get clogged with debris & starve fuel flow. Since your engine did start, it proves that you have adequate compression at the cylinders, which is the other reason she wouldn't start. I know that you have the raw water intake shut off while you crank for long periods, otherwise you can flood the engine. If these 2 ideas don't work, then I would suggest hiring a marine mechanic to perform a compression test & check the fuel pressure of the injector pump. Lastly, if your fuel is old & contaminated it may be a simple as pumping out the old diesel for fresh fuel. Try to feed the motor from an auxillary fuel tank with fresh diesel.
Good luck & let us know how is its going.

 

[SailorRob]

Just to add to what jrowan said, I had some trouble with the cap on my Racor fuel filter once and I didn't notice but there were air bubbles getting in there. Might be worth a check.

 

[jakez]

Jake, I'm sure a commented before since I also have a 5411.
Your engine problem sounds like its not getting enough fuel.
You said you checked the fuel lines, but did you actually pull out the fuel pipe in the top of the fuel tank? I had a problem like yours on my last boat's motor, a Yanmar, & found that there was wire mesh screening pushed in the inside end of the fuel tank pipe to act as a pre-filter. In reality it acted like a pre clogging device & starved the motor for fuel. There is also a small mesh screen located on the intake side of the fuel pump at the engine that can get clogged with debris & starve fuel flow. Since your engine did start, it proves that you have adequate compression at the cylinders, which is the other reason she wouldn't start. I know that you have the raw water intake shut off while you crank for long periods, otherwise you can flood the engine. If these 2 ideas don't work, then I would suggest hiring a marine mechanic to perform a compression test & check the fuel pressure of the injector pump. Lastly, if your fuel is old & contaminated it may be a simple as pumping out the old diesel for fresh fuel. Try to feed the motor from an auxillary fuel tank with fresh diesel.
Good luck & let us know how is its going.

Thanks for your reply... you were correct, although the problem wasn't originally the fuel. After I'd done the other work, I changed the filters and bled the lines... just didn't do it correctly.

 

[jakez]

Thanks to all of you for taking the time to reply... here's the wrap up so anyone searching on this forum can use this as a guide:
I think that originally the problem was a combination of the original wiring, an older battery and some corrosion on connectors. In the process of changing and checking the wiring, I took a dremel and polished every nut and and connector in the engine compartment. My glow plugs were definitely not working at 100% when this problem started. In the course of changing out the wiring I had replaced the fuel filters. I bled the line at the filter correctly, but the one at the injector pump I mistakenly loosed the outer nut only -- the proper way to do it is to hold that outer nut and loosen the inner one.... that way you see the bubbles and can tell when the air is gone. I got some help bleeding the line and with the new wiring, polished connectors, etc the engine now starts as quick as my car. I hold the plugs on for about 15 seconds (as opposed to 30 - 45 before), turn the key and it goes. I think that it all needed to be done, but who knows what the exact cause or combination of factors was that kept it from starting up. I highly recommend rewiring the ignition system if your boat has the original and also, clean all the contacts on occasion. I've had this boat for about a year, and the engine compartment was really the only place that was neglected over the years, and I knew that. I've been slowly tiding it up, but it caught up with me in this case.

 

[jrowan]

Jake, Glad you got the problem sorted out. Its amazing how a little air getting into the lines can completely prevent a diesel engine from starting. This is why I'm hesitant to ever replace a fuel filter on a good running engine, as bleeding the air out of the lines after preventative filter maintenace can be murder. When the 5411 is running right, I've never heard an engine start faster. When I turn the key its BOOM, instananeous starting. But if the motor doesn't get warmed up by glow plugs first, you could crank the devil out of her & she won't start for ages. In my experience every problem that I've ever come across on a diesel failing to start was caused by a fuel problem.

 

[colinhulse]

5411

Why not eliminate the fuel delivery system for a test. set up a container with a hose and gravity feed above the fuel pump with a Quart of diesel in it. If you run fine like that, then it's time to rework the tank and everything else up to the pump.