Intermittent Oil Pressure

[Slidin' Sam]

Ok, so I have a s14 Silvia (sr20det). The oil pressure gauge is reading kinda funky. So at idle the the oil pressure gauge is reading about 2 bar and goes up to around 6 bar while the engine is under a load. This is normal. But once the engine warms up (55-70C) the oil pressure will not go above 4 bar while under load and will idle between 0 and 1 bar. The gauges used in this car are Omori. The gauge appears to be working fine and I don't see how the gauge could work at cold temperatures and then at warm temperatures be reading 2 bar lower under all conditions. So my question is what is causing all of this? If the oil pump was going out, it would read low oil pressure ALL the time, right? The car run's strong and oil looks straight. Anybody have any ideas as to what may cause this?

CLIFF NOTES: Oil pressure is perfect when car is cold, but once the car is warmed up/race the oil pressure goes to shit.

Thanks!

[DoriftoPnoy]

IIRC per FSM idle pressure is at 11psi/.75bar. Is this an electric oil pressure gauge? If so, take it off and get a mechanical one. If the mechanical shows a higher/more stable reading then you're electric sender is probably bad. If it is showing the same, then something else may need replacing like maybe a pump.

[Slidin' Sam]

It is a mechanical gauge. When the engine gets warmed up, or after racing, the oil pressure will be reading zero or slightly above. I was thinking that the spring behind the gauge may be going bad, but when the engine is at operating temp and the gauge reads zero, the spring itself and the ss braided line leading to the gauge are not hot. Thought process is that if the spring is going bad and get heat, it would possibly cause the gauge to read incorrect...not too sure though.

[Slidin' Sam]

Never thought I would do this in this section, but BUMP! Does anybody have any ideas at all?...this is a really wierd condition...

[liv2drift045]

Maybe the oils too thin?? I had this problem on my cefiro and I narrowed it down to the oil pump. It started after I installed the oil cooler. Took the cooler back off and it still did it. Changed from omori to defi and it didnt change.

On one of my soarers, it would do this after a long run (like say late to work driving kinda hard on the highway), when i get to the toll booth at the end, the oil temp would be kinda high and the press would be really low, like under 1bar.

So my two theories, just do an oil change (thicker oil maybe/or just new oil in general)... or worst case, oil pump.

Hope that helps. Hopefully its just the gauge or oil and not the oil pump.

[fliprayzin240sx]

Oil pump is on its way out...you can bump the oil pressure a bit by running a thicker oil but in the long run, that pump needs to be changed. I usually run 15/20-50W on my SR, specially in the summer...

[jamanrr]

Oil pump is on its way out...you can bump the oil pressure a bit by running a thicker oil but in the long run, that pump needs to be changed. I usually run 15/20-50W on my SR, specially in the summer...


I was running some mobile 1 oil and when it would get into 90+c degrees and I had not changed the oil in a while (am in the process of doing oil analysis) it would go low as the viscosity broke down. I am thinking about switching to a 10 40 weight to maybe bring it up a little. Yeah like the others have said if you run it during the summer under higher temperatures the oil breaks down quicker and loses protection especially on modified engines.

[fliprayzin240sx]

^^^From what I've noticed in the 8 yrs I've had an SR...even 10-40W is too damn thin. Also, watch out in running Mobil 1. It slowly layers this film on parts that helps it lubricate better, but the problem is on the oil drippers for the cams. It has a tendency to clog them in the long run...

[KiLLeR2001]

^^^From what I've noticed in the 8 yrs I've had an SR...even 10-40W is too damn thin. Also, watch out in running Mobil 1. It slowly layers this film on parts that helps it lubricate better, but the problem is on the oil drippers for the cams. It has a tendency to clog them in the long run...

I'm using Castrol Synthetic 10-40, I live in Florida where it gets hot as shit, and I've noticed definite oil consumption over time, what brand would you recommend at 20-50 weight?

[Slidin' Sam]

Well thanks for the input guy's. No here is a quick question. Does anybody know if the oil pump from a NA SR is the same as a Turbo SR? Also, Flip, what oil do you use/recommend. I have alway's used Mobil 1 and never had any problems. I also race my car a LOT so I change the oil out about once a month, so I think I flush the system before any consumption may start?

[fliprayzin240sx]

I've been flipping between Mobil 1 or Royal Purple out here...If you have been running Mobil 1 for a while, wouldnt hurt to lift your valve cover and check the condition of your cams. If they seem scarred, pop the drippers off and clean them out.

[Slidin' Sam]

Well, I am about to pull my head off and replace the gasket and drop in some brand new poncams on MY car. Are you in Misawa? Then engine in question is on our missile/practice car.

[fliprayzin240sx]

Nah, im down in Oki...

[jamanrr]

I will be switching to this then run it a while then do an oil analysis.

what do you all think about this

My dumb ass thought I blew my car up today until I realized that a coupler had blown off at 18.5 lbs of boost. Always double check the easy stuff first.

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http://www.amsoil.com/StoreFront/images/RD30_900.jpg

[Slidin' Sam]

Amsoil makes good stuff.

18.5lbs of boost doesn't mean anything to me! lol I function in bar/kpa/celsius lol

[jamanrr]

Amsoil makes good stuff.

18.5lbs of boost doesn't mean anything to me! lol I function in bar/kpa/celsius lol

1.3 ish bar roughly. Yeah I wish we would go by that as well.

[Slidin' Sam]

yeah, that'll do it! I blew a coupler off once while I was boosting .7 bar, but that's because the driveway at upgarage sucks and my car is too low! lol