Bob, 2 Bar for oil pressure is very low for my 914, for any other than
idling speed with very hot oil.It much more commonly runs around the 4 Bar
level. 2 bar is actually the warning limit for the Flydat system when it
starts flashing lights at you! Shell VSX4 came out in various articles as
the clear top choice as I remember it. I wouldn't be happy running generally
at as low a pressure as that. I would be inclined to check your oil
pressure sender if you can, then change your oil, (for VSX 4) then if still
low put a shimmy in the oil pressure relief valve under the gear box.
Regards, David Joyce, G-XSDJ
----- Original Message -----
From: "R.C.Harrison" <ptag.dev@tiscali.co.uk>
Sent: Wednesday, September 12, 2007 11:37 PM
Subject: Europa-List: Rotax 914 performance info request....
> Hi! All
> Today I began to enjoy fuel economy..!
>
> I and my observer brother did a 2 hour 2 landing trip with a couple of
> timed climbs commencing initially at 1370 lbs and used only 24
> litres(best capable measure since I wouldn't claim a scientific
> measure!). Ambient temp/pressure was 22deg C /1024. Generally the
> Manifold pressure was maintained to 27 inches excepting a timed
> 1000ft/2000ft. 100% power climb at 85kts
> 80seconds.... one hour later (fuel used lighter) 1,500ft/2500ft...115%
> power climb at 80kts..60seconds ...I failed to collect the manifold
> pressures during the climbs. However the intake manifold locally
> insulated surface temperature was 31.1deg C during the initial climb
> and 35 deg C during the high power climb. 100- 110kt cruise 5,150 RPM
> the intake manifold temp at 2000ft was 27.4 deg C. (but in this instance
> the manifold pressure was 29")
> Intake manifold temp. at 1000ft 70kts was 30.8 deg C . At 100kt cruise
> the coolant temperature was 92 deg C . Oil temperature was 98 deg C with
> oil pressure at 2 bar.
> I am using "Mobil One" 0w -40w and find myself wanting to increase the
> oil pressure somewhat although the light viscosity oil must be "reaching
> places where more viscous oils don't reach !" Would anyone care to pass
> comment on the suitability of a higher oil pressure and the generally
> accepted best climb speed, please?
> The engine does not now appear to be using/loosing oil from
> engine/turbo.
> The rising coolant temps. on the sustained 115% climb would not have
> enabled a 5 minute climb.
>
> Would any capable statistician care to crunch/"nit pick" these figures ?
> and make appropriate recommendations with regards to the oil pressure ?
> and does anyone have any comparable intake manifold locally insulated
> surface temps without an intercooler fitted?
> A radio test at 20nm 2,000ft was effected at "fives" abeam and
> approaching Humberside Radar an item near impossible with the Jabiru
> installation!
>
> Regards
> Bob Harrison G-PTAG
>
> PS the stabilator torque tube clamps worked fine and won't need any heat
> to remove them !!!!!!
>
> Robt.C.Harrison
>
>
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