diesel problems...on a CD 27

[RonE58]

Well, I finally had my first shot in this new season to go out after work for a late afternoon cruise on my CD 27. After a few try's the diesel kicked over. As it was idling I prepared the sails. Just as I was about to let the dock lines go she stalled. I quickly started the diesel again and let go of the dock lines and motored about 50 feet., where she stalled again for the last time. Fortunately I had enough momentum to get to the bulk head and tie myself off. Other than last falls winter prep I never dealt with a diesel.

I used my diesel manual and went thru the first part of bleeding the fuel system. I loosened the plug and operated the fuel pump manually has they suggested until the air bubbles seized. But that was a far as I got.

Any suggestions or should I seek a qualified diesel Mechanic?

[Bill Cochrane]

Chances are you can solve this yourself, and learn a bit about your diesel in the process.

You say you started the bleeding...refer to the manual and complete the steps; it should have you starting with the bleed point closest to the fuel tank and working toward the injectors.

One question is how the air got in there in the first place. Did you open the fuel system when winterizing (change filters, for example?) If so, bleeding may well solve the problem.

If you have not done something (such as change a fuel filter) which might have introduced air into the system, and you see bubbles when you bleed the lines, you have an air leak and need to find it. It will be before the fuel pump, as after the pump the system is under pressure and a leak will let fuel out, where prior to the pump the system is in vacuum and a leak allows air in.

A quick first step would be to go through and tighten all hose clamps on fuel lines from the tank to the engine. Then run the engine at the dock and see if it will run for 30 mins or so without stalling.

Another place to look is the lift pump, which uses a diaphragm which can wear out and develop leaks.

A more thorough check is to plug the fuel filler vent, and work out a way to pressurize the tank with a bicycle pump, then look for fuel leaks. With this setup, if fuel is leaking out under pressure, air can get in under vacuum.

On the other hand, if you are not seeing bubbles in the fuel as you bleed the system, there is another problem. If the engine runs reasonably well before stalling, the injector pump ($$$) is probably OK.

If you haven't recently (in terms of engine hours) changed the fuel filter(s), you may want to check to see if they're clogged up with crud (technical term) from the bottom of the tank, as this could also be a problem that bleeding would not solve. You may need to bleed the engine if you change a cartridge-type filter (open system = air in).

The other possibilities would be the lift pump and the fuel shutoff (normally used to stop the engine) activating at the wrong time.

Diesels need clean fuel (no bubbles) and clean air to run; they need to spin fast enough at start to develop compression. Pretty simple to troubleshoot.

[Mark Yashinsky]

were you getting air(bubbles), when you started bleeding the system? Since the engine started (and restarted) when you had the initial problem, would think that an air lock fuel system is not the problme, unless you have a loose fuel line somewhere. Maybe start with the two things that a diesel needs a supply of to run, air and fuel. When was the last time the air filter was changed and how dirty is it. When was th elast time the fuel filter was changed and how dirty is that. Do you have a vacuum on the fuel filter to tell you that its time to change the filter (aftermarket)? If the engine is slowly being starved for either, it will not run for long.
What engine do you have?

[RonE58]

Thanks for responding Bill and Mark,
I went back to the boat this afternoon, and completed the bleeding process following the manual. First though I replaced the second fuel filter that I was unable to do last fall.
It was the first time I ever really took an interest in how the engine works, now I know the complete circuit of the fuel feed pump, filter, return pipe, injector valve, the high pressure pipe and the fuel injector pump.
The yanmar ysm 8 diesel however still doesn't start. I am thinking now could it be water in the tank. If so what would be the best way to extract the water and or fuel from the tank?.
When I attempt to start the engine with the choke out it just dosn't turn over.
Thanks RonE58

[John D.]

Why do you think it is an air leak?

Starting, running, and then stalling also can indicate a clogged filter (it might idle, but will stall if you give it more throttle), or a blocked vent on the fuel tank (it will run again after the vacuum bleeds away).

My CD27 originally had an outboard bulb on the fuel line. You could bleed in a flash. But it is not ABYC approved, and I removed it.

[marilou]

I was not aware that diesel engines have a choke.

If, there was a problem with the return fuel line the engine would perform as mentioned.

I do have a primer bulb attached to the fuel line - out line at the tank - and find it very useful. With the bulb you can tell if fuel is going thru the system by hearing, or seeing, the fuel return to the tank.

Engine - Westerbeke 13A

[marilou]

Make sure it's operating, adjusted correctly.

[Andy Denmark]

Hi Ron,

Diesel engines don't have a choke but most of them do have a fuel shutoff knob that stops them immediately if it's pulled out. Your problem could be a simple as mistaking this for a choke.

Maybe this has been your problem all along?
________
Vapir Oxygen Vaporizer

[Brian2]

I had a similar problem one spring. The engine just wouldn't start. After bleeding the lines and checking what I could, I finally submitted and had a yard mechanic look at it. While he was re-doing everything I had already done, I noticed that the fuel shutoff cable had come unattached from the fuel shut off lever, and the fuel shutoff was in the off position. It was then a simple fix.

brian

[RonE58]

Hi Ron,

Diesel engines don't have a choke but most of them do have a fuel shutoff knob that stops them immediately if it's pulled out. Your problem could be a simple as mistaking this for a choke.

Maybe this has been your problem all along?

I guess my years of having an outboard are still with me. Its is not a choke but a shutoff knob as you stated. I was operating it like a choke by pulling it out before I started the diesel and then pushing back in after I had it going for some 20 seconds or so.
I will head back down after work today a try starting the diesel again, this time by not touching the shutoff knob until I want to shut it down, of course.
Thanks,
Ron (duh!)

[viejo]

If that review doesn't prove fruitful, make sure that the exhaust is spitting water. Some engines will stop at a certain temp rather than continue to run and self-destruct.

Check the raw water intake to make sure it's open.

[Ann and David Brownlee]

Ron's got our previous boat. Although we learned how to do it, we don't think we ever had to bleed air from the system. Even after changing the fuel filter, the engine was able to cope with the air that had been introduced. We hope it's just a mix-up about the shutoff knob!

[RonE58]

Yes, I see water coming out the exhaust. As the Brownlees said I bought the CD 27 last sept and sailed her up the coast from Maryland to NYC and had the boat out a dozen time form then until take out in Novemerber, I never had a problem starting her, first shot every time.
This spring I started her 3 or 4 times before I went out the other day for the first cruise. Although it was wrong, I did start the boat each time, this year any way, by pulling out the (kill switch) for 15 seconds or so until it turned over. Left her running for 5 minutes or so and then shut her off. Why it worked though 4 or 5 times I don't know. . It still didn't turn over after I tried to start her with out touching the kill switch. I am going to hang around the dock to day and take some further suggestions.
I will let you folks know.
Thanks,
Ron

[Bob Qualls]

This is a flyer, but I'm wondering if the engine is acting starved for fuel before quitting. The symptoms are very similar, a primary difference in my experience was that the engine RPMS would slow then resume then slow befoe finally giving up. When air gets in there is no gasping for breath (or fuel) - it just dies.

Robin

[Bob Qualls]

Grins. I'm was checking my email from Bob Quall's computer when I posted the fuel lift pump theory. Bob says I'd better be right since his name is connected with it. In my experience, when the fuel lift pump was failing, it exhibited symptoms before it actually died. I'd be motoring along and the engine would slow - I chalked it up to a slug of bad fuel because the engine would get back up to the cruising RPMS. It would also typically start without a problem. But one day, as I was cruising along, I felt the boat slow, and then the engine quit. When it didn't start after bleeding, a changed the filter. When it still didn't start, I was towed home. Ultimately it was determined to be the fuel lift pump. I was able to replace it myself. Of course, after you do that, you have to bleed the system because you get air in when you replace the pump.

Robin Meigel
s/v Pacem
1979 CD 27 - with newly faired deck and Awlgrip painted topsides.