Hight Fuel injection pressure upon shutdown???

[Captain_John]

Hey guys, maybe this has been happening for the past year and 350 hours and I haven't noticed it, or it hasn't...

I happened to keep an eye on the Fuel Pressure after shutdown from the mechanical pump. I saw it slowly climb to 50 PSI from 25 PSI after several minutes then drop over the next few minutes to 25 PSI and lower.

I was wondering if this was a result of boiling or some other effect. Is it normal? I don't think it is harmful, as the system can handle those pressures easily.

...thoughts???

CJ

[Bevan]

I've seen this too when the mixture is cut-off and fuel selector valve is closed. The expanding fuel (due to FWF temps rising following shutdown) has no where to go so the pressure in this section of fuel lines increases. This is the section where the pressure transducer is located.

Next time you see this, push the mixture forward or open the selector valve and see what happens.

Do you have hot start trouble?

Bevan

[Captain_John]

I am sure that if I pushed power and mixture forward, pressure would have dropped and fuel would have come out of the sniffle valve.

My hot starts are fine. Sure sometimes I have problems when I botch the process... But dont we all sometimes screw up?

CJ