Fuel problems on a Beta

[donm]

Took the tank out over the winter and steam cleaned it. Put clean diesel back in and replaced the watertrap filter and the engine filter, bled it through and started it. It ran and then stopped. Bled and started again and ran ok. Stopped it and left for 15 mins and tried to start again – no go, so bleed and start and so on it goes. Disconnected and blew through all of the pipes again – all clear. Changed the water trap filter again – all ok. But still the same result. Each time the fuel falls back and I have to bleed it again to start. Sometimes it will run for 15 minutes without any problem, but if I stop it and leave it for 5 mins, the fuel falls back and off we go again bleeding to start..
The last job before I seriously start unbolting bits is to change the engine fuel filter again. Anyone have any ideas? The engine is a Beta 20 hp – never gave a problem before.
/forums/images/graemlins/frown.gif /forums/images/graemlins/frown.gif

 

[bazobeleza]

lift pump ok?
have you bled through the high pressure side ?(after the injector pump)
have you checked all unions and pipework?

 

[donm]

Thanks for this.
Lift pump sucking like a goodun. Plenty of fuel to pump and injectors. All joints tight and no sign of leaks.

 

[smeaks]

is the prefilter/trap above the tank? if so check the the seals on the bolt and drain, they have let me down before, not a quick ingress but enough to put a bubble in the system allowing the leg back to the tank to drain.

 

[donm]

Yes it is so I thought this could be the cause but I used all new seals first time round - and then took the whole thing out again including the housing and re-assembled it with more new seals. Still no improvement

 

[essexboy]

Thats the snag with diesels, taking in air without leaking fuel out. What about tank vent ? Check its not partially blocked.

 

[PetiteFleur]

Hi, I had a similar problem after I installed a 25HP Beta about three years ago. I'd also installed a new tank and fuel lines. It was fine for the first few hours and then when in Holland motoring against a F4/5 it suddenly stopped, but restarted immediately but only ran for a few seconds before stopping again. A passing dutchman towed me into the nearest marina, but as the wind was strong, as soon as I was alongside a pontoon and secured he carried on. I changed both fuel filters, it started fine and ran for about 10-20 minutes under load before stopping again. This happened several times before I gave up and rang the Beta agent in Ipswich. When I described the symptons he immediately said 'fuel problems - you have an air leak somewhere' Check and tighten all connections on the fuel line and when started and running, just 'crack open' each injector in turn. He said that an air bubble can collect in the injector on Beta engines. I did as he said and had no more trouble.

 

[willie4646]

every time you bleed the system, does air bubbles come out of the bleed screw? if so you definately have a broken line / joint somewhere. Try fitting a hose from the lift pump to a can / bottle of fuel direct and see if this cures the problem.
Willie

 

[donm]

Cleaned it out when I cleaned the tank

 

[donm]

Done that and every other joint whilst the engine was running

 

[donm]

Pretty sure that this is where I am so replacing some of the fuel lines is the next stage

 

[pampas]

Air leak before pump, Forgotton to do one connection up tight?

 

[donm]

Definitely an air leak - I have followed the line from tank to pump and tightened every joint in sequence. I have not used any thread tape or sealant. Don't like to as there is always a chance it could be pushed out of the joint and into the line but should I try this?

 

[srp]

I always use Hylomar on fuel line compression fittings. I always assemble the joint, back off the nut and smear a small amount on the olive, so there's no chance of it clogging up the bore of the pipe.
I also use proper hose tails for all copper to rubber joints - I've seen loads of installations with bits of rubber hose clamped straight on to a copper pipe with a hose clip - just asking for leaks.
I have to admit that my experience with PTFE tape on household plumbing has always been bad, so I've never used it on the boat for anything.

 

[pampas]

Then if you are certain all connections are air tight then you probaly have a slight leak in a pipe length, bet its in a section that has been disturbed .What type of pipe is it? if all metal check for hair line cracks where the nipples are brazed on.

 

[donm]

Mostly copper, one of which I had to pull back carefully to remove the tank. No sign of any leaks but replacement of fuel lines is the likely next step.

 

[donm]

Thanks. I will get a tube and do as you suggest - I'll try anything now!

 

[Fascadale]

We had what sounds like a very similar problem with the same engine.

After making all the checks you have made, at least twice we made up a copper pipe with a tyre valve on one end and a regular union type fitting on the other end.

Connected this pipe into the system, shut the valve at the fuel tank and started pumping air into the system.

We eventually traced the leak to the seating of the primary, watertrap filter, which we had already checked at least twice.

Good luck

 

[KINGFISHER 9]

Call Seastart.

 

[donm]

Thanks very much for this - every little helps!