Oil Pressure to the max when cold

Engines, Transmissions & Final Drive questions and answers

Moderators: timk, Stu, -alex, miata, StanTheMan, greenMachine, ManiacLachy, Daffy, zombie, Andrew, The American, Lokiel

User avatar
Fuzzlet
Racing Driver
Posts: 1077
Joined: Sat Feb 25, 2006 6:35 pm
Vehicle: ND - 2 GT
Location: Berowra
Contact:

Oil Pressure to the max when cold

Postby Fuzzlet » Fri Sep 12, 2008 7:05 pm

My NA8 with around 15k on its engine does this aswel...
Current: Red 04 SE (Slightly modified) - 133rwkw@7psi - Winner of the Mania Dyno Day 2008
Previous: Titanium 04 SE (Standard)
White 94 NA (Severely Modified) - 180rwkw - Runner up at the Mania Dyno Day 2007

Fatty
Speed Racer
Posts: 3175
Joined: Fri Feb 03, 2006 10:39 am
Vehicle: NA6
Location: Melbourne

Oil Pressure to the max when cold

Postby Fatty » Fri Sep 12, 2008 8:16 pm

the type of oil you're using has a big influence here... what are you using?

Keith
Fast Driver
Posts: 241
Joined: Fri Jul 25, 2008 10:07 pm
Vehicle: NC
Location: Hunter region

Oil Pressure to the max when cold

Postby Keith » Fri Sep 12, 2008 8:39 pm

Mine does the same but only since it had the Mania 100,000 k service and the elf oil put in. It quickly goes down as the oil warms up. I expect its something to do with the properties of this particular oil. You are not Robninson Crusoe so I wouldnt be worried about it.
O6 Marble white NC ;91 Malibu Gold NA 1800 BP4W;1990 BRG LE hardtop, unmolested, original; 1993 Brilliant Black hardtop, unmolested, restored.

Fatty
Speed Racer
Posts: 3175
Joined: Fri Feb 03, 2006 10:39 am
Vehicle: NA6
Location: Melbourne

Oil Pressure to the max when cold

Postby Fatty » Fri Sep 12, 2008 8:44 pm

my castrol edge 5w30 does the same thing as well... yeah i wouldn't worry about it.

Juffa
Racing Driver
Posts: 1751
Joined: Sun Apr 27, 2003 11:00 am
Vehicle: ND - 2 GT
Location: Bayside - Melbourne
Contact:

Oil Pressure to the max when cold

Postby Juffa » Fri Sep 12, 2008 9:16 pm

'At cold temperatures, the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up, the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would. The result is that at 100 degrees C, the oil has thinned only as much as the higher viscosity number indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a 20 weight oil that will not thin more than a 50 weight would when hot.'

Copied from here ==>> http://auto.howstuffworks.com/question164.htm

J
Former owner of Mailbu Stacey, Smurfette and Tweety.

Sheck
Racing Driver
Posts: 550
Joined: Thu Apr 29, 2004 9:54 am
Vehicle: ND - 2 GT
Location: South East Brisbane

Oil Pressure to the max when cold

Postby Sheck » Sat Sep 13, 2008 4:25 am

i work with oil all day long and the most commong is 15 w 40, at 100 deg C (well 99.9 to be exact) the oil has a viscostiy of approx 15 centistokes (dont know spelling but it sounds like how i spelled it) its usually more like 10-13. and at 40 deg C its like 100 or so centistokes so i'm guessing the 15W40 means that at operating temp 80-100 the oild will be between 15 and 40 centestokes. What i;ve read on a lot of material about oil is not what i see in my lab..

Dave

User avatar
MxJadeMonkey
Fast Driver
Posts: 472
Joined: Thu Jan 19, 2006 9:58 pm
Vehicle: ND - 2 GT
Location: Blue Mountains
Contact:

Oil Pressure to the max when cold

Postby MxJadeMonkey » Fri Sep 19, 2008 1:42 am

My NA6 has done that for years!

not too worry mate!
1991 NA6 Velocity Blue (Ford Colour)


Return to “MX5 Engines, Transmission & Final Drive”

Who is online

Users browsing this forum: No registered users and 2 guests