Air in line ??

[Joew2604]

I have a 1975 35 ft Gulfstar with 2 Perkins 4-154 engines which for the last 10 years start and ran fine. I run them at least weekly with no problems. About 6 moths ago the port engine would turn over fine but would not start. I bled the system and it fired up and ran good. Kept running both engines at least weekly for about two months.THEN port engine would turn over but not start. This time I just primed the pump and opened up No.1 injector nut till fuel came out and engine started and ran. Tightened everything up again and continued to run engine at least weekly. THEN about two months and again port engine wouldn't fire up. Primed pump and slackened of No.1 injector nut until fuel came through and engine started again. Ran it weekly, all fine, then the other day, port engine would not fire up again. Seems like air getting in somewhere, but where ???
Any info or suggestions would be appreciated as to where to start, or what to look for. I have checked all connections for fuel line, injector pump and fuel pump. Thank you.

 

[boatpoker]

Check hose and lift pump diagphram condition.

 

[Conall63]

Bad lift pump? Not an expensive item. So inexpensive, everyone who has one should carry a spare.


Conall

 

[Irish Rambler]

As others have advised check the connections, lift pump etc but you should have a non return valve in your fuel line, it may be blocked, or some tiny particle lodged between two faces in the valve stopping it from making a good seal.
Take it off, clean it thoroughly with WD40 and try and blow through it, it should be air/fuel tight. When refitting be sure to put it back in the correct way to allow fuel to flow to the engine.
I once changed a fuel line fitting and enthusiastically overtightened the nut and distorted the olive and the end of the copper pipe.
Endless hassle as I checked every connection until I realized my own stupidity and after fixing it gave myself a mental kick up the !.
Check any fuel line connections you've recently worked on.

 

[crashley]

air leak at the filter orings or injector pump

 

[Conall63]

FYI. Most fuel line fittings with metal to metal seals and seats should go together dry. Use a generous dose of brake clean prior to assembly and then a blast of air if you have a compressor on board.



Conall