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Red Line or not?

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pcanonge

pcanonge

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I have heard good things regarding Redline motor oil. My XJ 4.2 seems to loose a lot of oil pressue once warmed up. I'm considering a Synthetic oil such as Redline 20-60 or a Mobil 1 20-50. Does anyone have experiance with these oils in there Jaguar motors? I'm not convinced Castrol 20-50 is the way to go anymore.

P
 
I have used the Castrol Syntec synthetic for many years and have been pleased with the results. I have found that the oil pressure doesn't appear to drop as much once warmed and I believe maintains a more consistent viscocity throughout the temperature ranges, but I'm sure there are others with far more technical knowledge about this than me.
 
Jags of that vintage often have a problem with a bad sending unit. Befoe switching oils or viscosities, eitgher replace the sending unit or have the oil pressure tested with a reference gauge.
 
Thanks to all for your input. The collective experiance I find in this Forum is invaluable.


MrTVR, I will plan to try Castrol Synthetic when I change the oil next go around.

Maynard,
I will definatley get a reference for the oil pressure.

Thanks Again
P
 
Howdy,

I just replaced the sending unit and the Gauge read 40 pounds at idle. By the time I checked for leaks and took another look at the gauge I have 0 oil pressure.

OK I re-installed the original sending unit and now I have 0 oil pressure...

I'm thinking bad wires, poor ground. I cleaned the connections.... (could be the problem)

I could use some suggestions. I'm frustrated and spent a chunk of change on a new sending unit for nothing.

Thanks
Patrick
 
Yeah!!!
I finally received my oil pressure test equipment and have a baseline for my XJ6.
The oil pressure maintains 40 lbs at 2500+ rpm and 20 lbs at idle 600 rpm after reaching running temp.
I’m assuming this motor does not have the 168K on it the previous owner claimed.
Will a 4.2 last that long?

Patrick
 
Easily, with proper maintenance.
 
Check the ground connection for the guage. Rotate the tach CCW and it will come loose. You can then reach in through the Tach opening in the dash to get at the thumb screw for the battery guage and the oil pressure guage. Check and clean the blade contacts on the guage as necessary to see if low end pressure reads any higher. The blade connectors are prone to corrosion and gradual lower readings as a result.
 
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