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Posted by: CG-914 Sep 21 2016, 11:56 AM

Yes I did a search

First: 2.0 Type 4 engine... With a Mallory Distributor.

I've done some research for the sending Unit for my VDO Oil Pressure Gauge 0-5 bar.

The threat in the engine case is M10x1 Tapered.
VDO offers a 0-5 bar Sending Unit with the right threat (even tapered) and two connecters: one gauge and one idiot light.
VDO Part# 252.21.67

My question now is, does anybody have experiance of mounting it directly on the case? Especially in the car with the sheet meatall installed? Als does that work with the clearance to the Mallory Distributor?

Thanks C

Posted by: BeatNavy Sep 21 2016, 12:08 PM

Most people use an extension hose of some type so they don't have to modify the engine tin. I would also think it would make your concern about fitting by the Mallory a moot point, too. Some people use the hose from a paintball gun. I went with this option: http://www.autoatlanta.com/Porsche-Oil-Pressure-Sending-Hose-Extension-Kit-Parts-PN-RVDO150752.html

Pricey (well, it IS AA), but it is metal and grounds itself so you don't have to wire up something specifically for it. I think it may hold up better than a paintball gun hose, too.

Posted by: Vacca Rabite Sep 21 2016, 01:57 PM

Gotta use a hose.
Grease gun hose works, as does paintball gun hose.

Also, dont get the dual pole sender. Get the single pole sender and use a T block or Y block. That way you can use the stock idiot light AND the sender. The dual pole sender will light up the low oil light at a much higher PSI then stock, giving you false positives for low oil when the oil is hot and you are stopped at a traffic light.

Zach

Posted by: N_Jay Sep 21 2016, 02:00 PM

Make sure the hose end is metric threaded. The think nylon tube that comes in mechanical gauges works fine.

Posted by: Mark Henry Sep 21 2016, 03:08 PM

1/8" NPT is about a .98 metric pitch, it fits in the M10x1.0 no problem.
I've seen it done since forever... never have I seen it strip a case.
Since NPT is a taper thread don't go crazy tightening it down.

Posted by: N_Jay Sep 21 2016, 03:33 PM

Go back and forth twice tightening enough each time to seal, and watching how many turns and you will see the effect.

It only works because you are cutting new threads each time.

Eight turns and you have moved the crest into the root somewhere along the way.

Posted by: Racer Chris Sep 21 2016, 03:46 PM

27 TPI vs 25.4 TPI.
You'll never get 8 turns with a 1/8" NPT fitting in the M10 tapered hole, due to the diameter.
More like 3 turns and its tight. Not the best, but it does work.

(edited: to correct NPT thread pitch)

Posted by: N_Jay Sep 21 2016, 03:47 PM

http://www.pacificcustoms.com/cnc896.html

https://www.amazon.com/Speedhut-Metric-Adapter-inch-M10X1/dp/B00B5W9MGK

Posted by: CG-914 Sep 22 2016, 05:13 AM

Thanks guys. I was really hoping not to need a hose, but I have to make the most of it... I will try to use an M10x1 adapter on the case and then back to M10x1 at Sending Unit, because I relly want to use one for a bar gauge...

Posted by: Mark Henry Sep 22 2016, 07:18 AM

Don't forget the sender must be grounded to work, use a steel strap screwed to body metal or engine tin.

Posted by: Vacca Rabite Sep 22 2016, 07:30 AM

I also had to use teflon plumbers tape on the threads to get them to seal. I've seen some here say you don't need to do that, but I did. As mark said, this means you do have to use a grounding wire from the body of the sender to the engine somewhere. I just ran it to the common grounds, but it could be anywhere really.

Zach

Posted by: era vulgaris Sep 22 2016, 07:58 AM

Do not use a grease gun hose or a paintball gun hose. While they are more than adequate for the pressures involved, they are not rated for the temperatures involved in being screwed onto an engine.

The grease gun hose on my old car melted at the collar on the end that was screwed into the case, and resulted in oil getting everywhere. Chris at Tangerine Racing sells a SS braided hose with metal fittings. It's not on the website yet (I don't think), but you can contact him directly about it. I got one for my old car, and would never use anything else.

Here are pics of my old hose and the new one:
http://www.914world.com/bbs2/index.php?showtopic=272383&hl=oil+hose

Posted by: N_Jay Sep 22 2016, 08:10 AM

My guess is if you needed tape EITHER the threads were wrong, or someone in the past used the wrong threads.


P.S. 1/8 NPT this 27 not 24 TPI!