Bouncy oil level gauge....

[lateapex911]

So, long story short, my oil tank is out, and I'm refinishing it. Which means the level sensor is out. It's OE, from '73. Now, the level gauge has always (and by that I mean as long as I've owned the car, ...1993) done this flickering thing. Up down. Rarely in between. I realize that the gauge only is intended to read right at idle, warmed up.

Looking at it, it's a contact on a wipe. Looks sketch. Sits in oil. It's got the expected corrosion on the outside, but looks..... functional. I guess. Maybe.

So, there are a few options to replace...
Pelican sells the URO for $75. Or the Porsche for $229. About

So, questions are: Is the current wacky behavior just the way it is, so just paint and put the old one back in....old stuff is charming anyway?

Or...
No, it should be less spastic, most don't bounce around, replace while it's out, but save the big money, go URO, it's a joke gauge anyway.

or...
The gauge actually acts ok with the real deal Porsche float sensor, just suck it up and do it right, never look back.


Or??
Thanks

[darrin]

how does your gauge read when sitting level at idle, fully warmed up? Think about how the oil's going to a) slosh around in the tank while driving, and b) empty/fill via the dry sump/pump. As the level changes (constantly) while driving, the level sensor is going to bounce up and down. If your gauge reads accurately and the needle's rather steady when stopped at idle with a warm engine, I'd stick with what you have.

[proporsche]

check your ground connection on the oil tank

Ivan

[lateapex911]

Even at idle, when the oil checks out as "full", it is up...up...down, up....down, up.,down, etc.

In the middle? ha.

I've had the tank out previously, and the behavior didn't change....ergo, I'm leaning towards "not a ground". (But yea, grounds on oil tanks, not unheard of!)
I'm putting the engine back in so I'd love to make the decision now, as opposed to pulling it out right after putting it back in! Seems to me there's no way to wiggle the sensor out while the tank is in, and getting the tank in and out is begging to scratch it up.

[reclino]

I have taken a 1974 level sender to bits recently, and it had the same symptoms you describe.
Page 15? Of my 1986 barn find thread.
"Barn find" 1986 911 turbo
One important detail I noticed on the 1986 sender vs the 1974 was parts of the pivot that would provide the path to ground were silver plated on the later 1986 sender. Silver, even if it's tarnished is conductive.
After cleaning the 1974 sender and tightening up the pivot it works great.

[lateapex911]

So, in looking at the sender, it looks like the halves are fastened with a bent over flanges, and it looks like a super small split washer thing on the sender pivot. So, did you split the halves? Then just drive the washer tighter??
On my float, there is zero damping, it flops from limit to limit with no resistance.

I'd assume that I could put a VOM meter on the signal tab and ground and I should see a difference?
Anybody know the specs? I'll google...

So, on edit, resistance values are 0 thru the winding, then at the end of the range on one end it goes to 1.X M ohms.
When I check the resistance with just my probe tip from the windings to ground, I get resistance of like 90 to 200 ohms or so. Hmmmm

[reclino]

Take a look at page 15 of my build, go into detail on how I fixed the issues. It is supposed to move freely, the oil in the tank will slow the movement. Your twitchy needle is likely an electrical issue of the ground path within the sender being bad. Take the halves apart, (bend back the sheet metal tabs); clean it all up, and lightly polish the pivot shaft so it makes good contact. You may need to tighten up the float arm to the pivot like I did. Then put it back together.

[lateapex911]

Great info, thanks!

Looks like fun

[reclino]

A bit tricky bending the tabs back over without distorting anything. Only bend the. Enough to JUST get it to bits.

[darrin]

I had the same jittery oil level needle problem, replaced sender with a new one (bought Porsche version YEARS ago for around current URO price) and oil level needle smoothed back out.

[lateapex911]

Yea..prices of things OMG