Oil pressure sender

seafeye · 11-11-2016, 05:06 PM

My motor doesn't have an oil pressure sender. No idea why. What parts do I need to install one? Does it fit on the front of the motor or on the back beside the oil thermostat?

Ayles · 11-11-2016, 06:06 PM

Mine came sans sender as well. I id'd the engine and bought the applicable parts from our host. Install was super easy.

DRACO A5OG · DRACO A5OG's Garage

Did the wiring loom have the wire?

Trackrash · Trackrash's Garage

On the older motors/cars some had only a warning light and some had just a gauge.

Later cars had both pressure gauge and a warning light.

It appears your motor only has the warning light switch. You could replace it with a pressure sender. Later motors had the switch mounted as yours is and the pressure sender was mounted with an adapter in the right hand cam oil line.

Walt Fricke · 11-11-2016, 08:40 PM

Seaf - you will get better advice if you mention what year motor this is.
And what car you plan to install it in.

seafeye · 11-12-2016, 09:24 AM

Ok. The engine appears to be a '77 2.7l. It's twin plugged. I have an oil pressure gauge but no sender. I got the pressure sender now from our host but need to figure out where to install it. And what adapters I'll need.

seafeye · 11-12-2016, 09:28 AM

I figured it could go here. Will I need to get a shorter oil line?

Ayles · 11-12-2016, 09:33 AM

Here's my thread from a couple years ago. Hopefully some of the pics are helpful.

Oil Pressure Sender

Trackrash · Trackrash's Garage

Your oil line will work. You will need a different fitting that goes in the engine case and the adapter for the sending unit.

I have the pressure fed tensioners, but they won't make a difference.

seafeye · 11-12-2016, 10:20 AM

Awesome thank you.

Walt Fricke · 11-12-2016, 02:49 PM

Ayles picture in post 14 he refers to is the standard way the 2.7s (and the later SCs and Carreras) had their oil pressure sensed - a biggish steel block, through which a long hollow bolt with radial holes holds it to the engine case. The cam lines for this are shorter than what you have, but are easy to get - for instance, everyone who switched to pressure fed tensioners has their old ones in a junk box if they haven't thrown them away.

But the banjo in Gordon's picture is how Porsche did it on earlier models, and it works fine with the right parts. Just be careful about the sender. They come in two thread size flavors. One is 10mm, and another is a whole lot larger. You can get the steel block for either, but the banjo you can get (at least easily) only for the 10mm size.

since your car has an OP gauge, chances are good that the wire for it extends back at least to the 14 pin connector. If you don't have a wiring harness for the engine which has the wire for the OP, not awfully difficult to add one to the 14 pin plug. You may need to visit a Porsche junk yard or get help here to find the pin to add to the engine side of your 14 pin connector to mate up with what is on the chassis side of that connector. Or, if you are OK with being crude and making life tough later on, you could just splice into the OP wire before it disappears into the 14 pin fitting. But you really want to be able to have just the 14 pin part, and a CD box connector, to pull when removing an engine, or putting it back in.

Walt Fricke · 11-12-2016, 02:52 PM

Here is another idea - you can purchase an oil pressure sender which has both the idiot light switch and the pressure sender combined. That you just screw into where the idiot light switch is on the flywheel end of the engine.

Just be sure that you get a sender which matches your gauge. If the gauge is 10 bar or 150 psi, get a 10 bar/150 psi sender. If it is a 5 bar gauge (you haven't told us the vintage of the car), you need a 5 bar/75 psi sender.

mreid · 11-12-2016, 04:07 PM

Mine is screwed into the block by the thermostat and breather (1978 3.0, now 3.2ss).

Walt Fricke · 11-12-2016, 04:15 PM

That works, but you give up the idiot light function. Personally, I use aftermarket idiot light senders which give a warning at 20 psi. The stock one is maybe 0.2 bar? Way too low. However, a stock engine may well idle down at 10 psi just fine, and have good pressure at driving revs.

Flat6pac · 11-13-2016, 10:23 AM

The post 9 is 73/possibly 74 too
The larger block is the base for the large base 75 on
You require a 0-10 atm sender. I ncluded pictures of what I have spare. PM for pricing.
Bruce

RD911T · RD911T's Garage

Good info, this is relevant to the question I was going to post. My 82 3.0 going in 71 T body had a sending unit with a 10mm base threaded into an adaptor that was 17-18mm that threaded into the block in the oil line. When I tried to remove it to give me some clearance to install the fan strap and shroud it was corroded enough that the sending unit 10mm thread snapped off in the adapter. I have a 10 bar Druck meter. Should I just eliminate the adapter and get a 10 bar sending unit with an 18mm base? All I can find on Pelican are 0-5 bar units with the large base. Pics below:
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Adapter - 18mm?

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Broken sending unit - marked 0-10 bar - 10mm

It was a pain getting the broken sending unit out and the threads are a little buggered even after chasing a tap through the adapter 10mm threads. I'd prefer to eliminate the adapter.

RD911T · RD911T's Garage

Good info, this is relevant to the question I was going to post. My 82 3.0 going in 71 T body had a sending unit with a 10mm base threaded into an adaptor that was 17-18mm that threaded into the block in the oil line. When I tried to remove it to give me some clearance to install the fan strap and shroud it was corroded enough that the sending unit 10mm thread snapped off in the adapter. I have a 10 bar Druck meter. Should I just eliminate the adapter and get a 10 bar sending unit with an 18mm base? All I can find on Pelican are 0-5 bar units with the large base. Pics below:
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Adapter

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Broken sending unit - marked 10 bar

I found a URO 0-10 bar sending unit with 18mm base, it's for a Middie or early Turbo. The Porsche version is a little over 3 times the cost. Go for the URO?

Walt Fricke · 11-15-2016, 07:39 PM

No opinion on URO vs anyone else. But 10 bar is 10 bar, and threads are threads.

The steel block in post 15 comes in both 10mm and the larger (must be 18mm?) thread depending on what you want.

But your sender was mounted on the flywheel end of the motor? That's where the adapter shows up, as the idiot light switches maybe only are made in the 10mm version?

Trackrash · Trackrash's Garage

Quote:

Originally Posted by Walt Fricke

Here is another idea - you can purchase an oil pressure sender which has both the idiot light switch and the pressure sender combined. That you just screw into where the idiot light switch is on the flywheel end of the engine.

Do you have a part number or source for these?

Walt Fricke · 11-18-2016, 07:49 PM

VDO makes them. Google CB Performance, and you'll find a 5 bar one, but VDO also makes a 10 bar one if that's what your gauge needs. They generally are 1/8" pipe thread. That feels like it could screw into the M10x1.00 threaded hole, but it won't. The Porsche senders rely on a crush washer. to seal. Pipe thread relies on thread interference for its seal. The two are not compatible. Fortunately, it is easy to get an adapter - Autopower makes them, CB has them in its catalog.