High_Flyer
Well Known Member
Hi,
I have a RV-7 with a Aerosport IO-375-M1S engine.
Lately I noticed that my fuel pressure drops erratically when above about 8-9000 Ft. I saw as low as 10 Psi. When I switch the boost pump on fuel press goes back to normal, boost pump off fuel press drops again erratically.
This happens much frequently on hot days...
Here is a graph of the fuel press agains Pressure alt:
The positive peaks are when switching the boost pump on.
I suspect vapor lock, but I'd like more opinion.
What could be done to avoid this?
Thanks,
Alain.
I have a RV-7 with a Aerosport IO-375-M1S engine.
Lately I noticed that my fuel pressure drops erratically when above about 8-9000 Ft. I saw as low as 10 Psi. When I switch the boost pump on fuel press goes back to normal, boost pump off fuel press drops again erratically.
This happens much frequently on hot days...
Here is a graph of the fuel press agains Pressure alt:
![FPRESS_PALT.jpg](/community/proxy.php?image=https%3A%2F%2Fimage.ibb.co%2FiAmFKy%2FFPRESS_PALT.jpg&hash=50a1b0fb4e52eae0db928d7f3e034574)
The positive peaks are when switching the boost pump on.
I suspect vapor lock, but I'd like more opinion.
What could be done to avoid this?
Thanks,
Alain.