Anyone know off hand what the size and thread pitch for the stock oil pressure sender is? Just need to find out whether its M10x1.0, 1/8 NPT or 1/8 BSP. Since these blocks have a funky mix of metric, standard threads and BSP i figured it wouldnt hurt to ask..

 

To be sure, might want to exam an oil PSI switch at auto parts store.... easier than getting at the one you have

 

I did a little googling earlier and the TDI motors have m10x1.0 senders, that doesnt mean a whole lot though since the motor was designed by buick in the 50's. Looking at the diagram in RAVE though, it appears that the bung for the oil pressure sender is located in the same housing that bolts to the front of the motor where the oil filter boss is located. A piece like that had would have been re designed over the years so I'm leaning towards M10x1.0 but it could also be BSP.. They joys of working on franken motors.. :P

 

According to places that sell the oil pressure switch (STC4104) the thread pitch is 1/2x20 UNF.

 

of course its some screwy thread size where it's hard to find an adapter.. I see why people use the glowshift sandwich plate now, lol..

 

Glowshift sucks. Mine is 20psi OFF! WTF? They said its with in spec... BS.

 

Im not talking about their gauges, just looking at them they look like garbage. I run VDO or Autometer gauges.. I was hoping it was m10x1.0 as i have VDO gauge and sender i pulled from my vw after it was totaled.. I've got cheap earls sandwich plate i may cap off and drill out so it gets full flow to the oil filter and use that instead of spending money on the glowshift sandwich plate. I may try and find a 1/2-20 plug and just drill and tap it out to m10x1.0 and make it work. Is the stock pressure switch a low pressure normally closed switch? Any idea on what the opening pressure is? My vdo sender has a secondary low pressure switch that opens at 12 psi that i could use to drive the stock idiot light if the stock one is low enough pressure.

- just double checked and the low pressure warning light terminal on my vdo gauge operates at 7 psi and i found via some googling someone stated the stock switch has an operating pressure of 3-4.5 psi..

 

If you have any hydraulic shops in your area, check with them for an adapter. I have a modded RX-7 and wanted to know oil temperature. The only feasible place location was in the outlet cooler hose from the engine. The hydraulic shop in my town was able to provide me with a tee which provided a metric thread for the engine, a -10 male thread for the hose, and an NPT thread for the pressure gauge.

 

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