4108 perkins - fuel check valve

[Seadoc777]

Has anyone installed a fuel check valve on a Perkins 4108 between the engine fuel filter outlet and fuel line to the hi pressure injector pump. I am having starting issues with fuel drainage and air intrusion into system from the filter to the hi pressure injector pump.

[Lepke]

The line is probably sucking air, but if fuel if flowing back to the tank, then the valves in the lift pump are bad. Pump valves are like mini check valves and for fuel to flow backward, both need to be leaking.

[Seadoc777]

The lift pump is new.

[model 10]

There has to be an air leak. There is no place for air to come from unless you have a leak.

[Seadoc777]

Brilliant!

[djmarchand]

As Ecos noted above, your problem is likely an air leak in the fuel supply hose or tubing. Fix the leak. Adding a check valve is like a band aid.


David

[model 10]

Originally Posted by Seadoc777

Brilliant!

Sorry but no, just a simple answer. There is no way for fuel to back flow unless there is a leak somewhere, you just need to find it. The Perkins should run OK without a check valve and that's probably why nobody has done that mod.

[Compass790]

No I haven't installed a non-return valve in fuel line but agree with other posters advice.

[Compass790]

Forgot to say check your filter fittings & bleed screw ( if it has one ) Not uncommon to get leaks there.

[BruceS]

Friend had a similar problem on his Honda outboard. I put a couple of pound pressure on the line and found 3 leaks. Can you disconnect at the fuel tank & fit up a pushbike pump? Easier to see dripping fuel than looking for air going in.
Clear fuel lines when new can help see air bubbles?

[NoTies]

Originally Posted by Ecos

Sorry but no, just a simple answer. There is no way for fuel to back flow unless there is a leak somewhere, you just need to find it. The Perkins should run OK without a check valve and that's probably why nobody has done that mod.

It doesn't need to be an external leak. A rotary style pump can draw air back from the return line if lift pump or check valves are leaking.