Fuel tank hose exit/vent

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   Greetings all.  Hot down here in KY and was race committee, setting marks, going back and forth... suddenly engine started slowing down on its own almost to nothing. Able to set line, ran race and engine seemed ok.  Upon further review (and local engine guy) the issue seems to be the hose that leaves tank and vents to port stern rail. Boat came with a small glass jar midway between fuel tank and vent connection at stern and the hose goes under the bunk.  Local guy said I probably had fuel/fumes in line and the hose needs to be straight from tank to stern rail but with the bunk that can't work.  

How are your boats set up?  And is this the problem?  Guidance and advice needed please!   Thanks, :)bill

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WJRyan Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 12 February 2008 Location: Louisville, KY Status: Offline Points: 223	Post Options Post Reply Quote WJRyan Report Post Thanks(0) Quote Reply Topic: Fuel tank hose exit/vent Posted: 22 June 2013 at 9:03am
	Greetings all. Hot down here in KY and was race committee, setting marks, going back and forth... suddenly engine started slowing down on its own almost to nothing. Able to set line, ran race and engine seemed ok. Upon further review (and local engine guy) the issue seems to be the hose that leaves tank and vents to port stern rail. Boat came with a small glass jar midway between fuel tank and vent connection at stern and the hose goes under the bunk. Local guy said I probably had fuel/fumes in line and the hose needs to be straight from tank to stern rail but with the bunk that can't work. How are your boats set up? And is this the problem? Guidance and advice needed please! Thanks, :)bill
	Bill Ryan, Room4Crew, #155

Bill Layton Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 15 September 2002 Location: Canada Status: Offline Points: 551	Post Options Post Reply Quote Bill Layton Report Post Thanks(0) Quote Reply Posted: 22 June 2013 at 9:31am
	You are describing air in the fuel system. When it gets to the injection pump it slows down to an idle and sometimes shuts down. The original boat did not come with a glass jar midway in the vent hose... no idea what that is about I ty-rap my vent hose to the bottom of the wood cleat that supports the cushion on the engine bulkhead this helps prevent a low spot that fills with fuel..... leaving this aside, this isn't your problem. You need to bleed your low pressure and high pressure fuel system and be sure all gaskets are sealing. Once you bleed you will see the engine run normally. Edited by Bill Layton - 22 June 2013 at 9:32am

WJRyan Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 12 February 2008 Location: Louisville, KY Status: Offline Points: 223	Post Options Post Reply Quote WJRyan Report Post Thanks(0) Quote Reply Posted: 22 June 2013 at 3:36pm
	Had no idea there is a high and low pressure... I assume there are directions on how to do that? I did a quick search but nothing came up however I might not be using the right key words. I will align the line as well, there was fuel in it when I "drained" it, went right into the glass jar so I "assume" this has been an issue before me! Thanks as always Bill for your guidance, :)bill
	Bill Ryan, Room4Crew, #155

Winner Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 07 September 2011 Status: Offline Points: 222	Post Options Post Reply Quote Winner Report Post Thanks(0) Quote Reply Posted: 23 June 2013 at 11:13pm
	Even as a new Laser 28 owner I've had to do this a few times now. Once when I changed the fuel filter and at least one other time where inexplicably the fuel supply got choked off and the engine wouldn't start. Probably an air bubble. Refer to the pictures at the following link for more info: https://photos.app.goo.gl/1fuSg55WjavnGhxo2 Start by slightly loosening the slotted nut on the top of the fuel filer. (see pic #1) Then reach down below the fuel lift pump (just aft and below of the impeller housing) and your hand should find a lever. Push down on this firmly and pump until fuel starts dribbling out of the loosened nut. If you see air bubbles, keep pumping until the air bubbles are gone, then tighten nut quickly. (see pic#2) Turn your attention further up the line to a 10mm (I think that's the size) nut at the point where the fuel hose attaches to the cylinder head (see picture). Here it's best to have two people. Have lots of paper towel on hand and place some in the area below this nut. Loosen the nut a bit using a small ratchet or nut driver. Now, have someone in the cockpit turn the engine over while you stand by on the nut. WATCH YOUR HANDS AROUND THE SPINNING FLYWHEEL! (see pic #3) Diesel will start spilling out of the loosened nut and typically quite quickly (a few cranks of the engine), the engine will catch and start. At this point tighten up the nut very quickly until fuel stops flowing out and ask the person to kill the engine. Clean up any spilled fuel in the area and you're done! Edited by Winner - 17 July 2017 at 11:50pm
	Chris Eclipse #240 Thunder Bay, ON

WJRyan Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 12 February 2008 Location: Louisville, KY Status: Offline Points: 223	Post Options Post Reply Quote WJRyan Report Post Thanks(0) Quote Reply Posted: 24 June 2013 at 6:11am
	Thank you Chris so much, the visual steps are amazing and exactly what I need - the engine is a deep and mysterious place for me! Thank you very much! :)bill
	Bill Ryan, Room4Crew, #155

Winner Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 07 September 2011 Status: Offline Points: 222	Post Options Post Reply Quote Winner Report Post Thanks(0) Quote Reply Posted: 24 June 2013 at 11:04am
	Someone on these forums (Frank maybe?) once mentioned Nigel Calder's book "Marine Diesel Engines: Troubleshooting, Maintenance and Repair" and after reading it myself I also highly recommend it. The nice thing about diesels (or at least 25 year old marine diesels!) is that they are of relatively simple design without much variation from one manufacturer to the next. I went from literally not even knowing that diesel engines have no spark plugs to feeling at least moderately confident in doing routine maintenance and simple repair jobs. http://www.amazon.com/Marine-Diesel-Engines-Maintenance-Troubleshooting/dp/0071475354/ref=sr_1_4?ie=UTF8&qid=1372086085&sr=8-4&keywords=nigel+calder
	Chris Eclipse #240 Thunder Bay, ON

fatjohnz Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 05 August 2006 Location: United States Status: Offline Points: 296	Post Options Post Reply Quote fatjohnz Report Post Thanks(0) Quote Reply Posted: 25 June 2013 at 1:56pm
	Great pics Chris. I didn't know there was a hand lever for the lift pump! lol. That said, I have bled air out of the system by loosening various fittings instead. And to Bill Ryan, what I would say is to also look for diesel leaks along the fuel path. I had one fitting, at the pump exit I think, where the gasket had completely deteriorated. I had to re-seal that connection to stop her from sucking air (or leaking fuel). js

WJRyan Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 12 February 2008 Location: Louisville, KY Status: Offline Points: 223	Post Options Post Reply Quote WJRyan Report Post Thanks(0) Quote Reply Posted: 25 June 2013 at 3:57pm
	Book has been ordered and I haven't seen any fuel around the engine area or tank and I do look but... will examine in more detail and really bright light tomorrow. Thank you gents, I was really nervous and you have convinced me that I can make this right (yes, me!). Y'all rock! :)bill
	Bill Ryan, Room4Crew, #155

frfletch Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 13 May 2008 Location: Canada Status: Offline Points: 365	Post Options Post Reply Quote frfletch Report Post Thanks(0) Quote Reply Posted: 30 June 2013 at 5:28pm
	Just one additional thought of something that can cause the symptoms you indicate. That is a fuel filter that requires changing. If you have not changed it for years, and if you did not keep your tank full during the winter nor spiked with diesel conditioner, a sludge can accumulate and restrict flow at the filter. The engine will start, run fine for a while, and then as the sludge condenses against the fine media of the filter it restricts the flow and the engine runs down. When you let it rest, the sludge backs off and fuel can flow temporarily again when started. These filters are available from any automotive supply house for about 8 bucks or something like that. They just unscrew, be sure to fill the new one with diesel to reduce air in line, and then screw the new one on. Done! If that is your problem, you may consider flushing out your tank while you are at it. Cheers

khardy Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 22 June 2004 Location: United States Status: Offline Points: 132	Post Options Post Reply Quote khardy Report Post Thanks(0) Quote Reply Posted: 01 July 2013 at 7:44am
	two comments: 1) When I first purchased my boat, I had a similar problem. At the time, my boat had a check valve mounted on the tank outlet. This kept getting clogged with gunk. Finally I removed the check valve and never had this problem again. I'm not sure if the valve was original equipment or if the previous owner added it. 2) I found it difficult to use the engine mounted fuel primer lever. So I installed a fuel line pumper bulb in my fuel line between the tank and the engine lift pump. This is much easier to use.

Bill Layton Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 15 September 2002 Location: Canada Status: Offline Points: 551	Post Options Post Reply Quote Bill Layton Report Post Thanks(0) Quote Reply Posted: 01 July 2013 at 9:49am
	Yes that check valve was a poor attempt at a non return valve that the tank manufacturer supplied with the tank. I know a few owners that had to remove it. The fuel lift pump primer lever doesn't have the same throw as the pushrod. I always use the starter and crank the engine to bleed the system, unfortunately it means an extra person. I also use another person to hold the decompression lever down. Then I'm free to bleed without it starting, and I have all hands to bleed it properly. Edited by Bill Layton - 01 July 2013 at 9:50am

bal149 Members Profile Send Private Message Find Members Posts Add to Buddy List Skipper Joined: 14 August 2010 Location: canada Status: Offline Points: 67	Post Options Post Reply Quote bal149 Report Post Thanks(0) Quote Reply Posted: 01 July 2013 at 10:53pm
	yes, three hands are better than one. I am the one that recommended Calder's book- I had raced motorcycles for years and motors were not difficult to understand but diesels have a few particularities and once they were clear to me the running and upkeep thereof were easy to understand. If the motor won't run, it is fuel delivery only, unless there is a major obstruction to air intake such as you have blocked the intake with junk sitting on the intake which is unlikely, then there is a fuel delivery problem. This is easy to check. I would not go back to a gasoline engine with its multiple possibilities of dysfunction-air, fuel and electrics, not to mention the risk of fire. If the system needs pumping, check for leaks-a loose connection or deformed copper washer would do this. And yes a new filter is a good idea. I have installed a water separator on the outlet from the tank-overkill? Maybe.