SBT 951 Rave Valves

[eclipse]

Hello,
I am installing a brand new SBT 951 and I noticed that the RAVE valves are not holding vacuum, that is, when you push one down, it comes back up quickly.
Is the normal operation?

What is the correct direction for the one way valve in the RAVE valves supply line? arrow towards the RAVE valves? or engine?

Thanks!

[Bill O'Neal1]

Re: SBT 951 Rave Valves

The valve arrow points away from the motor as the function is to open the valve using pressure created inside of the engine cases.

The rubber diaphram can cause the valve to open by itself, so your vacume test is invalid.......

To test the diaphram, put a pump ( like a pop off tester pump ) on the nipple on the rave valve pod and pump about a pound or three into the diaphram to see if it somewhat holds it. It doesn't have to hold pressure for long, but it shouldn't just spew out either. It's function is just to push the valve open.

[eclipse]

Re: SBT 951 Rave Valves

Thanks!

Just for curiosity....what is the small hole on the upper side of the exhaust port for?

[Bill O'Neal1]

Re: SBT 951 Rave Valves

Do you mean the one in the actual clyinder exhaust port? If so, it could be used to activate the rave valve via the system used on the 787 engines if you drill through the rave valve base pod if you chose to do so. Otherwise it does nothing on the 951 configuration.

[eclipse]

Re: SBT 951 Rave Valves

Thanks.

How far do the guillotines usually potrude into the exhaust port while in operation?

[Bill O'Neal1]

Re: SBT 951 Rave Valves

They drop in until they hit the stops, or about even with the clyinder walls.

[1fastski.com]

Re: SBT 951 Rave Valves

any 951 that cant hold the rave down with vacume has run like crap . it should hold IMO anyhow . i have found it helps to grease up the shaft so the Orings swell a little on the SBT motors . after that they run great .