Troy,
We're using the VDO 360025 oil pressure sender for our remote unit
($26 in stock at JEGS, same but backordered at Summit Racing). It has
an auxiliary (warning) contact on it that remains grounded to the
sender case until the sensor reaches 11.4 PSI where the contact opens.
We used this signal to drive a 12V relay that powers our Hobbs and
"Low Oil Press" indicator. Works well.
The fitting at the engine is an AN816-4 (just like Bob's). To make it
difficult on simple airplane folks, the hot rod shops don't typically
list these fittings by their "AN" (Army/Navy) designations. Try
AER-FBM2512 (Aeroquip) or EAR-961604ERL (Earl's) instead if you're
shopping at JEGS or Summit. It's a steel adapter with an AN-4 nipple
on one end and 1/8"-27 NPT male thread on the other. Spruce still
faithfully uses the "AN" designations and will also charge you "AN"
prices.
Our sensor installation is a bit different than Bob's (... different
composite airframe, too). We used a bulkhead fitting (AER-FBM2821)
and attached a metal tab for the grounding lug via the bulkhead nut.
The whole assembly (sender + bulkhead fitting) is attached to the
aircraft via a #10-32 ClickBond stud and a cushioned (Adel) clamp. We
could have used one of the other NPT-to-AN adapters (AER-FBM2721,
NOS-16781NOS, EAR-998604ERL) but attaching the grounding lug seemed
problematic. Plenty of ways to skin the same cat.
Finally, we ran -4 stainless braided hose with steel AN-4 fittings
between the engine and the sender. The remote system works well w/ no
leaks or fires and good pressure readings.
If you want pics or a rough schematic just shoot me an email. Best of
luck with the build!
D
|