Hi all,
So this is the deal, we were at the boat show weekend before last. We were
the only car in the boat show. On the way back to the hotel the oil light
came
on and stayed on.
So the question is if I remove the oil pressure sending unit and screw in an
oil pressure gage what should be at an idle? And what would the pressure be
at
about 1500 rpm.
I understand the pressure will be dependent on the condition of the motor
but
please give me some approximate numbers.
Thanks a lot, Tommy in Tampa
=================
Tommy,
Except for the oil pressure switch's indicator light cutoff threshold at 5
to 7 lbs. and the oil pressure relief valve specs, there appears to be no
mention of acceptable OPERATIONAL oil pressure ranges in the Amphicar
_Maintenance Manual_, so below is a brief sampling gleaned from various
Triumph sites concerning oil pressure in engines that are similar or at
least very close relatives to the Amphicar's 1147 cc standard unit.
From what one reads "out there," it looks like about 40-60 pounds of
pressure with a thoroughly warmed engine at 2000 rpm would be a safe value
for any Amphicar, whether fitted with the stock 1147 cc engine, or if this
has been replaced with some other larger unit such as a 1300 (1296 cc) or
1500 (1493 cc) Spitfire engine. Since different Amphis' idle speeds can
vary greatly, this is certainly a less reliable benchmark. If your Amphi
engine's getting a little tired, and you're measuring closer to 40 than to
60 pounds at 2000 revs, then you might squeeze another couple-few seasons
before a rebuild is necessary by stepping up from the 10W30 recommended
weight motor oil to a 20W50. This will likely bring up the pressure a
couple-few pounds. Needless to say, I would recommend AMSOIL's Synthetic
20W-50 High Performance Motor Oil (API Service SG, SH, SJ, CF, CF-2, CG-4,
CH-4, CI-4 JASO MA) AMSOIL Product Code: "ARO" for this application. (AMSOIL
purchases also help pay the rent on the Amphicar.net website. See
http://www.amphicar.net/amsoil/ for more details).
Anyhow, below's the poot from various Triumph sites
~Bilgey~
EXCERPT FROM "General Dimensions, Weights and Capacities of the Triumph
Spitfire" at <
http://www.triumphspitfire.com/Size.html>:
Oil warning light -- Extinguishes at 3 to 5 lb/in2 (0.21 to 0.35 kg/cm2)
oil pressure
[NOTE: According p. 1/45 of the Amphicar _Maintenance Manual_, the oil
warning light should go out at 5 to 7 lbs.]
EXCERPT FROM "TR6 Oil Pressures" at
<
http://www.vtr.org/maintain/oil-pressure-TR6.html>:
I thought I would relate my experiences with TR6 Oil Presure, based on my
engine before and after my engine rebuild of a few years ago:
A fresh TR6 engine Oil pressure values:
Cold Idle 90+
Cold Running 100
Warm Idle 40
Warm Running 70
A worn TR6 engine might look like this, based on my engine before rebuild:
Cold Idle 50
Cold Running 70
Warm Idle 15
Warm Running 50
EXCERPT FROM "Jeff's Classic '67 Triumph Spitfire Mk3 Site" at
<
http://www.totallytriumph.net/spitfire/auxillary_gauges.shtml>:
[...] A Spitfire engine should produce between 40-60 PSI when the engine is
fully warm and pushing about 2,000 RPM.
Excerpt from "Triumph Spitfire Mk IV" at
<
http://www.laffey.co.uk/triumph/triumphspitfire.php>:
[...] Oil pressure ... ... 40 to 60lb./in.sq at 2,000 r.p.m.
