Engine/Fuel Not Sure ???

[RON SCHERER]

After a nice sail down San Diego Bay we were heading back to the slip running, if I remember correctly, at 2000 R.P.M. when all of a sudden the engine slowly lost power and shut off. I waited for a couple of min. and hit the starter and much to my surprise it started but would not run over about 1000 R.P.M. We made it back to the slip OK.Can anyone give me an idea what this might be? Thank you,Ron

[Rick McCall]

We had a similar experience this weekend. We were cruising along at 2300 rpm with not a breath of wind when the engine starts smoking badly and the rpms drop until it stalls. Can start it up in neutral but it won't run in forward or reverse.
It ended up that the shaft and prop were wound tightly with thick strands of cedar bark. Hired a diver the next day to clear and everything was fine afterwards.
So you may want to check and make sure nothing has fouled your shaft/prop.

[RON SCHERER]

Rick--Thanks for the help but I can go just fine in forward and reverse but if I try to go over approx. 1000 rpm it wants to stall out. ??????? HELP!

[RON SCHERER]

I should also mention that I had the engine serviced and all new filters 20 hours ago. ????

[Ray & Sandy Erps]

Diesels need three things to run, fuel, air and compression.  It's probably a fuel problem.  I'd check to make sure there is enough fuel in the tank and then I'd check the RACOR to make sure it's tight and it's not sucking air.  After that, it gets a little harder.

[David Baer]

Same problem recently on Sea Fever. The boat had just come out of the yard and during service the tech had left the air cleaner housing just a bit loose.  It rotated to the starboard until the neck came in contact with the engine compartment insulation,  which formed a very effective seal, ,blocking almost all the air flow. Result was no power, lots of black smoke and no idle.

[Ken Heyman]

Ron,

Sounds like air in the system and/or bad fuel. I would change your filter and re-bleed your system. By the way, I have also experienced my engine restarting after it loses power and dies, run for maybe 10 minutes and then lose power and die again. At this point it will not restart without the system being bled (my experience).I'm just curious, How long was it running at the reduced RPM. If your filters are badly clogged (after 20 hour of running time) you may want to consider some of the other remedies discussed in this forum i.e. tank cleaning or replacement. As I learned, the screen on the end of your fuel pick up tube should also be removed. Mine had been sucked into the tube thereby restricting the fuel flow.

Good luck,

Ken

[RV61]

Ron,
Last fall I found my RPMs and thus speed would drop off from time to time and I could not ever get the speed up over 6 knots or rpms over 3000. After researching
the board I decided I may have a fuel starvation issue. Replaced all the filters and pulled the pickup tube out of the fuel tank and found the screen on the end of the tube was full of black crude. Removed screen. That pickup screen I believe was the culprit as I had regularly changed filters. Boat know cruises at 6.3-6.5 knots on a calm lake at 3200 RPM.  While I was messing with the tank I took a sample off the  bottom of the tank using a kerosene pump and found the fuel to look fine however when I run this tank of fuel down I will pull tank and clean or replace.

[Tom Glennon]

I had a similar problem.... finally isolated it to the bleeder screw in the water separator filter.  The screw had loosened, resulting in air getting into the system.  Good luck.

[PAUL T.]

Rick...... What engine do you have in your boat? If it's the original engine, cruising RPM should be 2100 to 2600 RPM. Just a thought........PAUL.

[RV61]

Paul,
Thanks for the catch. It is the original engine and the RPMs on my gauge are off by approx 1000. I should  typed could not get over 2000 and after
screen removal I cruise at 2200  rpm.  I need to fix that guage but sailing is luckily getting in the way right now.

[Paul Blumenfeld]

Ron,

Had similar issue last summer.  Slowly lost RPM and then engine quit in shipping channel.  Engine started later and stopped again until it would not start at all. Found dirty fuel filter.  Had tank "polished" but if I had to do it again would replace tank per other postings on the board.  Polishing cost 1/2 of what a new tank would cost.  

Paul

[Ron Hill]

Ron : ALWAYS list your hull # and if you have an engine question WHAT engine you have - sure saves alot of GUESSING!!!!

I'll guess that your engine is not getting enough fuel or air -- most likely fuel.  Pickup tube screen? Air in the system?

You need to start trouble shooting the fuel system at one end and go all the way to the other.  

[RON SCHERER]

Thanks to everyone who replied. My hull # is 367. Engine is M-25. Number 500222. The engine was serviced at the 803 hrs. It now has 823. The man who serviced the engine commented to me about how clean the fuel looked when he did the work. I do not know the history of the fuel tank. I would like to trouble shoot this problem myself so I can learn, but the boat is 6hrs away and the time is precious when we go to her if you know what I mean? Im afraid Im one of those guys who have to depend on the professional to hammer the problem in a hurry even tho it costs me. The bad thing is Im not learning a darn thing and that can come back and bite me if you know what I mean? Any more feedback is appreciated. Thanks Ron Scherer

[Ron Hill]

Ron : I'll speculate that you need to pull the fuel pickup tube and that you have a clogged screen in it's end. Removed that screen!!!!!
We've been thru the pickup tube screen discussion MANY times - it's also in the Mainsheet Tech notes.