Hi guys...a buddy of mine is having probs with his scsi 503 fitted to a trike..
In flight in the cruise at say 5000rpm...sometimes when he goes to full power to climb he finds the engine starts bogging with the EGT on the rear cylinder PTO end dropping quite a bit...EGT on the mag end staying normal.
Its an intermittent problem...its doesn't bog every time.
He has tried all kinds....when he first told me the symptoms I suspected a problem with the vac/pulse operated fuel pump...take its impulse from the PTO end as you know guys.
But he tells me he has fully overhauled the pump with a new impulse line...below is a list of things he has replaced/done upto now.
"plug/leads/caps/coils swapped/all fuel pipes inc vacuum hose for fuel pump/fuel filter new/fuel pump fully serviced and cleaned /new egt senders and gauge/carb fully striped and cleaned/air filter cleaned/different angles tried for carb rotation/float level checked/new needle jet/new needle/new main jet/new pilot jet/new air screw o ring/air screw half a turn out/main needle clip 3rd notch from top/all low voltage connections checked at coils etc/primer bulb bypass fitted/new choke plunger fitted/new main jet gauze fitted(in float bowl)"
He also had the crank seals renewed 50hrs ago at de-coke time.
Any ideas guys.
In flight in the cruise at say 5000rpm...sometimes when he goes to full power to climb he finds the engine starts bogging with the EGT on the rear cylinder PTO end dropping quite a bit...EGT on the mag end staying normal.
Its an intermittent problem...its doesn't bog every time.
He has tried all kinds....when he first told me the symptoms I suspected a problem with the vac/pulse operated fuel pump...take its impulse from the PTO end as you know guys.
But he tells me he has fully overhauled the pump with a new impulse line...below is a list of things he has replaced/done upto now.
"plug/leads/caps/coils swapped/all fuel pipes inc vacuum hose for fuel pump/fuel filter new/fuel pump fully serviced and cleaned /new egt senders and gauge/carb fully striped and cleaned/air filter cleaned/different angles tried for carb rotation/float level checked/new needle jet/new needle/new main jet/new pilot jet/new air screw o ring/air screw half a turn out/main needle clip 3rd notch from top/all low voltage connections checked at coils etc/primer bulb bypass fitted/new choke plunger fitted/new main jet gauze fitted(in float bowl)"
He also had the crank seals renewed 50hrs ago at de-coke time.
Any ideas guys.
