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914itis
My drive to Hershey was flawless. I drive with the newly converted 6 for the first time a total of over 500 miles ov weekend.

The engine sounds great and handles great, however I have a glitch on the oil pressure gauge and light that I would like to figure it out and solved.

When the engine is cold and the car is idling at about 1200, the light is off and the pressure gauge goes up over the 3 mark, as the engine warms up it goes down to 1 at idle and will not go pass the 1 1/2 mark at any rpm as shown on the picture ;the light will come on at a full stop (1000 rpm)
I am using brad Penn 20x50 oil

I am wondering if it's the pressure sender or oil overfill.

All comments appreciated

The motor is 6yl stock 2.0
r_towle
Do you have an external cooler and thermostat?

914itis
QUOTE(r_towle @ Apr 23 2014, 08:34 AM) *

Do you have an external cooler and thermostat?


No, just an aftermarket (PMS) tank at the factory location using AN fittings
brant
Most likely loose tolerances (worn motor). And heats effect on the oil
SLITS
Can't speak for the oil light, but on flat sixes up to the 3.0L, the gauge was a 10 Bar (140 psig). Using a 10 Bar sender with a 5 Bar gauge might not work really well. Maybe you have a gauge / sender mismatch.

My gauge shows 0 at hot idle, but my oil light does not come on.

Overfilling will not cause a reduction in oil pressure. It will cause oil to be blown out of the tank thru the vent.

On cold startup, my engine throws 100+ psig at 2K RPM, but then settles down to about 10 psig per 1000 RPM.

Electrical gauges are subject to 40 year old wiring connections. I would buy a cheap mechanical gauge and plumb it in to verify your gauge readings.

914itis
QUOTE(brant @ Apr 23 2014, 09:16 AM) *

Most likely loose tolerances (worn motor). And heats effect on the oil

Oil temp looks to be ok .
76-914
QUOTE(914itis @ Apr 23 2014, 06:41 AM) *

QUOTE(brant @ Apr 23 2014, 09:16 AM) *

Most likely loose tolerances (worn motor). And heats effect on the oil

Oil temp looks to be ok .

I think Brandt meant the oil viscosity is effected by temp!
Randal
QUOTE(SLITS @ Apr 23 2014, 06:21 AM) *

Can't speak for the oil light, but on flat sixes up to the 3.0L, the gauge was a 10 Bar (140 psig). Using a 10 Bar sender with a 5 Bar gauge might not work really well. Maybe you have a gauge / sender mismatch.

My gauge shows 0 at hot idle, but my oil light does not come on.

Overfilling will not cause a reduction in oil pressure. It will cause oil to be blown out of the tank thru the vent.

On cold startup, my engine throws 100+ psig at 2K RPM, but then settles down to about 10 psig per 1000 RPM.

Electrical gauges are subject to 40 year old wiring connections. I would buy a cheap mechanical gauge and plumb it in to verify your gauge readings.


+1

Mechanical gauges are great and give you piece of mind. I had a big red light installed on my dash that would light up if low oil pressure was experienced. Motors are expensive and gauges or warning lights cheap!
stownsen914
QUOTE(SLITS @ Apr 23 2014, 09:21 AM) *

Can't speak for the oil light, but on flat sixes up to the 3.0L, the gauge was a 10 Bar (140 psig). Using a 10 Bar sender with a 5 Bar gauge might not work really well. Maybe you have a gauge / sender mismatch.


The above was my first thought ...

If you've got the right parts, sometimes they do go bad, so you can try swapping them out if you (or a budd) happen to have a spare.

Also make sure your ground is good.

Oil pressure is a really important thing to have right, so do figure it out before you run the engine much.

Scott
brant
QUOTE(stownsen914 @ Apr 24 2014, 12:56 PM) *

QUOTE(SLITS @ Apr 23 2014, 09:21 AM) *

Can't speak for the oil light, but on flat sixes up to the 3.0L, the gauge was a 10 Bar (140 psig). Using a 10 Bar sender with a 5 Bar gauge might not work really well. Maybe you have a gauge / sender mismatch.


The above was my first thought ...

If you've got the right parts, sometimes they do go bad, so you can try swapping them out if you (or a budd) happen to have a spare.

Also make sure your ground is good.

Oil pressure is a really important thing to have right, so do figure it out before you run the engine much.

Scott



I Agee you should figure this out.
What are the motor compression numbers and mileage.
Definitely worth trying the senders too
yeahmag
I always wanted to mount a mechanical sender in the engine bay. What are you guys running for a quality unit?
Cap'n Krusty
911s, even the 2 liter engines, run what most non-Porsche people consider scary low oil pressure. When the 2.7 came to market, Porsche changed the oil pressure switch for the light to one with a lower threshold so the light wouldn't come on at idle. At this time, that switch is what you put in all the air cooled 911 engines. If your switch is working correctly and the light comes on at 900 RPM, you're running at less than .5 BAR. That's around 7 PSI. If your temps aren't unusually high, if you're running 20w50, and your idle isn't less than 900 RPM, you may have a problem. First thing I would suggest is installing updated cam tower oil fittings. They're somewhat more restrictive and should raise your overall oil pressure a little. After that, you may have to look into major surgery ......................

The Cap'n
914itis
I just spoke to a local expert who confirmed the capt'n's post about the low pressure on these 2 litter motors. As far as the pressure gauge, I will try a mechanical gauge and see the results.

Compression was at 175 lbs all around .

Motor runs great.
914itis
Any recommendations , thread size on a mechanical pressure gauge that can be had at the local FLAPS?
914itis
Feeling better today, I pulled the sender and it is a 10 bar gauge. That makes me feel a lot better.
As always you guys nailed it!

now on the hunt for a 5 bar sending unit.
Steve
Pelican sells them.
I just bought one for my Tri gauge cluster
http://www.pelicanparts.com/cgi-bin/smart/...%2533%2529%2520
914itis
QUOTE(Steve @ Apr 26 2014, 11:25 AM) *

Pelican sells them.
I just bought one for my Tri gauge cluster
http://www.pelicanparts.com/cgi-bin/smart/...%2533%2529%2520


Thanks
That's a single . I need a dual sender .
Dave_Darling
How about this one, then?

http://www.pelicanparts.com/cgi-bin/smart/...C%252Ffont%253E

--DD
Steve
QUOTE(Dave_Darling @ Apr 26 2014, 10:42 AM) *


That would be equal to 5.5 bar. I guess that's close enough.
914itis
Picked up a 5 bar sender from the great Bruce . I got it today and my pressure is fine.
Thanks to you all.
SLITS
QUOTE(914itis @ Apr 28 2014, 11:15 AM) *

Picked up a 5 bar sender from the great Bruce . I got it today and my pressure is fine.
Thanks to you all.


smilie_pokal.gif
bcheney
So glad this had a HAPPY ENDING driving.gif
VaccaRabite
smilie_pokal.gif smilie_pokal.gif smilie_pokal.gif smilie_pokal.gif smilie_pokal.gif

Zach
r_towle
QUOTE(bcheney @ Apr 28 2014, 08:49 PM) *

So glad this had a HAPPY ENDING driving.gif

Happy endings are the best type.
914itis
QUOTE(r_towle @ Apr 28 2014, 09:36 PM) *

QUOTE(bcheney @ Apr 28 2014, 08:49 PM) *

So glad this had a HAPPY ENDING driving.gif

Happy endings are the best type.
this is what happened
when starting the conversion, I had a 10 bar gauge, then this one comes up in the classified, I like it better, I purchased it and install without ever thinking of the sender.

Ihad to find a sender quick, I couldn't digest having to embrace for the worst.

Happy ending indeed . beerchug.gif to all
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