Oil pressure sensor & gauge

[mkinne]

I would like to add a VDO oil pressure gauge to my center console.
Can anyone provide part numbers for appropriate gauge and sensor for a '73 2.0?

TIA
Matt

[thesey914]

Don't remember the part numbers, but when I fitted this gauge I used a 911 pressure sender (same M10x1.0 thread and is made by VDO)
Trouble is the sender fouls the distributor body so you'll have to find an appropriate oil hose.
VDO make a "T" piece so you can still run the oil pressure switch to operate the light on your dash.
The gauge I used is from a Golf GTI (VDO -measured in BAR) alternative cars would be the 944/924
Cheers

[mkinne]

I thought I had heard about a pressure sensor / switch that had two terminals; one for the analog signal (sensor), and one for the idiot light (switch).

Also, I thought the stock switch has a 1/8" NPT thread. Can anyone confirm which is correct?

- Matt

[Will98D]

I think if you look right in the Pelican catalog you'll see the dual sender (light/gauge). I have been told it is a 1/8" NPT also, and it's just what it looked like when I changed my sender a few months ago. A straight thread like an M10 x 1.0 would require a shoulder and a washer/gasket/etc. to seal properly, whereas the tapered pipe thread finally gets tight as it goes down into the hole and seals things up.

[Dave at Pelican Parts]

Yup to all of the above.

The sender is too large, so get the "adaptor kit" (a bracket, some hose, and an adaptor) or DIY with some grease-gun hose. Make sure to ground the case of the sender...

--DD

[mkinne]

OK...
Finally found the gauge and sensors in the PP catalog.
Last question: 80 or 150 psi for a stock 2.0L?

- Matt

[Dave at Pelican Parts]

80 PSI. A stock Type IV engine shouldn't get that high when the oil is warmed up. Cold oil can, but the 80 PSI gauge is fine for normal running.

--DD

[thesey914]

Originally posted by Will98D
I have been told it is a 1/8" NPT also, and it's just what it looked like when I changed my sender a few months ago. A straight thread like an M10 x 1.0 would require a shoulder and a washer/gasket/etc. to seal properly

The thread is M10x1.0. ( I'm 99% sure -the VDO "T" piece was labelled M10x1.0 on its packaging too) -NPT is American national pipe thread and is imperially measured. The 914 is built in Germany and therefore uses metric threads.
You are right about the straight thread needing a washer to seal it -the sender on the 911 has a crush washer/shoulder.
Cheers

[Dave at Pelican Parts]

Now for the funny part--
There is no standard for metric tapered (pipe) thread. So they use US standards instead.

The fitting in the 914 case was originally a metric size (M6??), tapered thread. But that is very close to a US size (if M6 is correct, that's 1/4") that the US size works just fine. More than fine enough, in fact--and most or all of the aftermarket VDO senders you can get are actually the US size!

--DD

[thesey914]

Dave, well I learn something new everyday......I looked on all my engineering thread charts and no tapered metric threads were listed.
Now I remember, when I screwed the sending units into the VDO "T" piece, they were tapered (they tightened on insertion) but the male end, that screws into the case I'm (98% sure) was a straight thread.....

Not trying to conduct a p*ssing contest, , and if it fits then problem solved

[Pump]

This thread is already pretty old, but it needs some clarification for those that read it for the first time. Don’t listen to those self-certified internet technicians and their theories. A 1970s German car design is 100% „Deutsche Industrienorm“ (DIN). All threads are metric. I just tried to replace an oil pressure switch on a 2.0L 914 and regretted it the second I turned the wrench. One of these self-certified YouTube hero’s managed to drive a SAE pressure switch into the M10*1, totally braking the thread. Meaning for whoever reads this thread:
The sender you are looking for is VDO 360-006 for the 80 PSI VDO gauge. It comes with with a copper crush washer. Since there are many „fakes“ with ⅛*27 thread out there get an M10*1 nut for $.50 from your local home improvement store. If it binds after 2.5 -3 turns you were fouled. For the 914 I recommend getting an oil pressure hose fitted from you local hose store for $15 with male and female M10*1 thread. Brake hoses might do the job as well, but I don’t know how temperature stable these hoses are on the long run.
Meanwhile I have to find a way how fix the damaged thread issue without having to take the engine apart.
Btw. The damaged thread might even be the cause of cylinder scaring in the adjacent cylinder.