T9.9 problems

[sherwin]

I thought my problems were solved when I reconfigured my fuel delivery
system with a 10 micron filter and new hoses. Generally, the engine is
running better with a tank of fresh gas.

However, after motoring on Lake Michigan for about an hour and later trying to restart it, the engine balked at starting. When it finally did start it died with a few coughs. It would then start, but die when put into gear. It took about 5 starts for it finally to run in gear. It ran fine for the remaining half hour to bring the boat back to the slip. I have no idea what caused this
problem, and hope it will not get worse. Usually, the engine is
reluctant to run in gear until it has warmed up a bit, but I can
somewhat accept that.

The other problem is a hesitation in the throttle when trying to accelerate
from idle. I have to turn the throttle about 30 degrees before the engine
picks up speed. My first thought was something about the high speed
carb jet, but it runs fine when it is over this 'hump'. I inspected the
throttle linkages, and saw no slack anywhere. What can be causing this
hessitation?

[boats.net]

If it has old style fuel pump on it it may be vapor locking, if fuel pump only has 2 hoses connected to it then replace fuel pump with water cooled version.

[sherwin]

T9.9 problems

Thanks for the reply.

Although this engine is a 2002 model, it has not been used very much, maybe
15 hours per season. It is an auxiliary for a sailboat, so we mainly use it for
going in and out of the harbor. I don't know offhand what kind of fuel pump
is on it, but your suggestion sounds like major surgery. I hope the solution
is simpler.

I would also like some advice about this throttle lag, which has plagued me
for many years. I think the linkages are tight, so what else can cause this
behavior?

Sherwin

[boats.net]

May need carb cleaned and new diaphram in accelerator pump in bowl of carb.