OM606- Sanity check fuel line air leaks
OM606- Sanity check fuel line air leaks
The secondary fuel filter on the fuel filter head (metal canister filter) is on the pressure side of the lift pump.
The T-fitting banjo is at the highest point in the fuel supply line.
Trapped air will collect at the high point and be returned to the tank as the engine runs (or by using the primer pump on an OM617 when the engine is not running).
On the OM617, the lift pump has two disc valves, one of which is a check valve to prevent fuel draining back to the tank (from the low pressure IP supply circuit) when you shut the engine off.
There is also a check valve on the engine side of the clear IP return line to keep fuel in the high pressure IP/fuel injector circuit.
A tight fuel system will have no air in the fuel lines.
Any fuel union is a potential point for air ingress.
The two basic principles above should apply.
On my OM617, if the IP gets air bound in the high pressure circuit (causing a no start situation), then I crack open the injector hard lines and crank the engine to more quickly purge the air out of the injector hard lines.
Once fuel dribbles out of all the injector hard lines, the IP high pressure circuit is re-primed.
Hope this helps.
On an OM617 the primary fuel filter (clear plastic pre-filter) is on the suction side of the lift pump.
The secondary fuel filter on the fuel filter head (metal canister filter) is on the pressure side of the lift pump.
The T-fitting banjo is at the highest point in the fuel supply line.
Trapped air will collect at the high point and be returned to the tank as the engine runs (or by using the primer pump on an OM617 when the engine is not running).
On the OM617, the lift pump has two disc valves, one of which is a check valve to prevent fuel draining back to the tank (from the low pressure IP supply circuit) when you shut the engine off.
There is also a check valve on the engine side of the clear IP return line to keep fuel in the high pressure IP/fuel injector circuit.
A tight fuel system will have no air in the fuel lines.
Any fuel union is a potential point for air ingress.
The two basic principles above should apply.
On my OM617, if the IP gets air bound in the high pressure circuit (causing a no start situation), then I crack open the injector hard lines and crank the engine to more quickly purge the air out of the injector hard lines.
Once fuel dribbles out of all the injector hard lines, the IP high pressure circuit is re-primed.
Hope this helps.
1 Guest(s)
1 Guest(s)