Hi All,

 

Got a quick question..... I was driving late last night and all seemed well. (Only nipped out for petrol) Anyways, just as I was pulling back onto my street I noticed that the Oil Pressure had dropped to zero!

 

Parked it up on the drive and cut the engine, it had been driving ok whilst I was out?

 

Anyway, let it settle for about half an hour and checked the oil level - all looked ok??

 

Started it up again and whilst it was idling, it read zero.... revved slightly and the needle did move up but then settled back to zero.

 

As it was late last night I've not checked anything else yet.... I'll take a look tonight however if anyone has any thoughts I'd be greatful.

 

Should I be worried? Only bought my JAE ticket yesterday:crying:

And you have checked the levels and also checked for leaks ?

 

Also worth to check the plug for the oil pressure sender is properly attached and clean.

The pressure senders on these are notorious for being crap as the years roll by - I've read about a lot of Zeds where the oil pressure gauge is temperamental.

 

I'd check everything as Lee suggested but, personally, I wouldn't be overly concerned. It's a known issue.

I personally dont beleieve my oem guage so i have added an other sender and a digital guage.

Yep this happens on my white zed regularly, just check check check those levels regularly too.

Thanks guys for your comments... hope your right. I'll check over it tonight and maybe let it run for a while to check for noises.

 

Its going back to Lee Dents the week after JAE anyway just for a full check over since the new engine. There is a very small oil leak at the front of the engine but surely that wouldn't reduce the pressure that much? Lee will be sorting this too when its back with him.

 

- - - Updated - - -

 

I've literally been checking all the fluids before any journey lol! So far so good

Just make sure you keep a top up can of oil in the boot just in case. I always have one in both zeds.

I usually carry some coolant too.

Think I will get an oil pressure, oil temp and water temp gauge installed soon

I have a full 5 litre bottle of both oil and coolant in the car:lol:

my oil pressure gauge has been pissing about for about 8 months now xD always works when its cold and sometimes works when its hot xD

So overall, am I right in saying as long as its got oil it should be ok?

The only way you will ever know what the oil pressure really is, is to remove the oil pressure sender & install an accurate gauge.

The oil pressure will be higher when the engine is cold compared to normal operating temperature.

The oil pressure specifications in the Nissan Service Manual state:

With the engine at operating temperature, under no load & at idle, the pressure should be more than 11psi.

At 3000rpm it should be between 51 & 65psi.

How easy/hard is it to fit an oil pressure gauge. Is it something that I should be able to do? I am not a mechanic btw, can only do the basics

How easy/hard is it to fit an oil pressure gauge. Is it something that I should be able to do? I am not a mechanic btw, can only do the basics

 

I'm sure Lee would fit it for you mate, I'd get a water temp gauge fitted as well.

I want a water temp one anyway after the last blow up! I had no warning.

 

All should be ok for next weekend though shouldn't it? I'm not taking it back to Lee's until the 19th

Should be, my oil pressure gauge doesn't work, need an aftermarket one fitting myself.

Time for a new oil pressure sender. If you had no oil pressure the engine would be very tappetty. Those 4 cams and 24 hydraulic lifters demand a lot of oil. Fortunately it's an easy fix. On the passenger side is the sender, by the engine mount. Unscrew it and screw in a new one, done. You can also wind in a 1/8npt iirc, 0-100psi pressure gauge as a test and take a manual reading for accuracy and peace of mind. These cost a few quid.

Hi Stephen, where about on the engine is it?

 

Any pics?

 

Also, would this be the part: http://www.ebay.co.uk/itm/Engine-Oil-Pressure-Sender-With-Gauge-Standard-PS-199-fits-85-96-Nissan-300ZX-/252055705601?hash=item3aafb0d801

I haven't I'm afraid but Google will throw up some pictures for you. Make sure you buy an OEM one rather than a pattern part. The pattern ones aren't much cop.

The oil pressure sender unit is on the left hand side (passenger side of rhd cars) in front of the turbo region, difficult to explain but if you get under the lhs you will see it.

Good luck..I am sure it is buggered.

My stock pressure gauge was temperamental for several years, but is now fine.

They are known to become erratic due to contamination due to irregular oil changes.

 

I resurrected mine by way of 2 lots of lifter treatment and several static oil changes (ie not driven, just warmed up) with a low cost oil, followed by the recommended quality oil. It has been fine ever since. It responds in line with the manual over all conditions now.

Very relieved to say the least, I am a bit of a gauge watcher I'm afraid.

(oil) contamination has nothing to do with it...the oil can not get to the "electronics" inside the sender and/or damage it in any other way.

the oil-pressure will push a small lever which makes 2 small contact-arms slide over a variable resistor-wire.

 

Over time these contact-arms get bend slightly out of spec and it will loose contact with the resistor-wire.

By simply bending the arm(s) back and clean the resistor-wire with contact cleaner, you can restore the sender and it will work fine again.

I have disassembled and rebuild/repaired several oil-pressure senders this way.

 

In the picture below you can see how it works, the contact-arms (yellow circles) slide over the resistor wire (red arrow) which will send the signal to the gauge in the dashboard.

 

Thanks guys.... I've been out in it again tonight. Drove really nice. Whilst engine was cool the gauge worked perfect... As soon as it reached operating temperature, the gauge literally died.

 

Car runs fine though, and all fluids at correct levels. If I get a bit of time this weekend I might have a look at the sender.:thumbup1:

(oil) contamination has nothing to do with it...the oil can not get to the "electronics" inside the sender and/or damage it in any other way.

the oil-pressure will push a small lever which makes 2 small contact-arms slide over a variable resistor-wire.

 

Over time these contact-arms get bend slightly out of spec and it will loose contact with the resistor-wire.

By simply bending the arm(s) back and clean the resistor-wire with contact cleaner, you can restore the sender and it will work fine again.

I have disassembled and rebuild/repaired several oil-pressure senders this way.

 

In the picture below you can see how it works, the contact-arms (yellow circles) slide over the resistor wire (red arrow) which will send the signal to the gauge in the dashboard.

 

 

I take your point, but I have to disagree.

Yes, the inner workings do not come into contact with the oil itself, but the mechanism responding to the line pressure does.

This movement then becomes restricted by contamination, hence why I recommended what I did.

Maybe a coincidence I guess, but it solved my problem without any other intervention.

As I said, my gauge now responds as if new.

The pressure senders on these are notorious for being crap as the years roll by - I've read about a lot of Zeds where the oil pressure gauge is temperamental.

 

I'd check everything as Lee suggested but, personally, I wouldn't be overly concerned. It's a known issue.

 

Yup - sender unit failing is a common issue.

 

If the engine sounds OK at idle, when up to full temperature, with no rattles - then generally you can assume all is well. Replace the sender unit (it's in the region of £100 for the OEM item) or fit an aftermarket gauge, if you want peace of mind!

I have a full 5 litre bottle of both oil and coolant in the car:lol:

 

I guess we can't be too careful with an old car........ Although (he says, touching all items made of wood and crossing all fingers and toes) I still do not - and have not had the cause to so far either....:clover: