Using a Porsche 912 oil gauge as a water temp gauge

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Using a Porsche 912 oil gauge as a water temp gauge

Post by flatfourfan »

So is this even possible?

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I have an oil temp gauge from a 912 incorporated into my triple set of gauges on my dash and I was thinking last night that it would be cool if I could get the oil temp gauge to show the water temp of the 2.0 8valver that i have out back. What does an oil temp start at anyway? 100c? Ideally I need temps from mid 80's.

pipe dream? Or is this feasible?


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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by beetlefanatic »

It should be possible. Normally the VDO sensors' ranges are 40-120 deg for water and 50-150 for oil. I'm talking about the ones you use with the 52mm round VDO gauges. Since your gauge does not show actual temperature with numbers, you should be able to use the oil temp sensor as is in the water circuit. If you have a water and oil sensor why not do a test with some hot water and a normal stick thermometer and compare where they show on the scale of your gauge, and decide then which one you want to use.
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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by flatfourfan »

damn...............surely it can't be as easy as that?

I guess that there will be a calibration issue with a generic water sender unit and the porsche VDO stuff?
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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by Dawie »

As Beetlefanatic said.

Remove temp sender from Golf engine. Connect sensor's sense wire and earth to gauge. Power up gauge with 12V. Now put sender into boiling water. That should be somewhere around 94- 96 deg at highveld altitude? See what the gauge shows.

Porsche and VW generally tried to stay with VDO gauge type sensor specs in the old days.
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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by acpaterson »

Oh, and ps. if you decide to install stock gauges for any specific reason, I get first option on these please..
:-)

regards

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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by flatfourfan »

In that case it's going to be easier to just hook the gauge up in the car to the sender as I know my temps stay rock solid at 95 when up to temp as that's when my fan switch is set to come on as well.

Will post the findings on my build thread regardless if it's successful or not.
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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by flatfourfan »

acpaterson wrote:Oh, and ps. if you decide to install stock gauges for any specific reason, I get first option on these please..
:-)

regards

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Nah..............I won't sell these ones boet........as the stock units (chinese) are a good R4500 without shipping and they're of suspect quality. These are the real deal german ones and I was lucky to get a smoking deal on them.
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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by acpaterson »

I know. just ragging you..

Just wish it was an easy process to FIND these bloody things.. I'm going to resort to alternative tactics.. And make Gauge Faces that "look" like the real ones.. if all else fails, DIY I say...
I made White Dials for my Burgman. Looks awesome. Cost me a few hours and some PC work. This tho would be difficult to get lighting to work etc.
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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by flatfourfan »

^^^^ yup, wouldn't take too much effort.

I looked around and you can even get auto gauge units that can be modded. That way, they are brand new. Roger is also working on a digital version, but the poor dude has so much on his plate that he doesn't know when he's going to get around to them.
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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by splitfan »

Gary the mp9 system uses a dif sender for water temp and im pretty sure it wont be compatible with you gauge , I would just plumb a VDO sender into a waterpipe and run that to the gauge.
My biggest fear is that my wife sells my cars for what i told her they cost !!
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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by retrovan »

acpaterson wrote:I know. just ragging you..

Just wish it was an easy process to FIND these bloody things.. I'm going to resort to alternative tactics.. And make Gauge Faces that "look" like the real ones.. if all else fails, DIY I say...
I made White Dials for my Burgman. Looks awesome. Cost me a few hours and some PC work. This tho would be difficult to get lighting to work etc.
Go to Speedo services, as they will make up a speedo set, that will look as good as the original..

There info..... We do repairs to car, truck and bike gauges, as well as customising of dials. We are situated at 18 Edendale Road, Eastleigh, Edenvale. Our cellular number is 0763742993, and our landline is 0116098960. Our email contact is info "AT" speedoserve .co .za.


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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by retrovan »

flatfourfan wrote:In that case it's going to be easier to just hook the gauge up in the car to the sender as I know my temps stay rock solid at 95 when up to temp as that's when my fan switch is set to come on as well.

Will post the findings on my build thread regardless if it's successful or not.
If not happy with the calibration, you can fit a Potentiometer or adjustable resistor in series to calibrate the gauge to your liking.

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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by flatfourfan »

splitfan wrote:Gary the mp9 system uses a dif sender for water temp and im pretty sure it wont be compatible with you gauge , I would just plumb a VDO sender into a waterpipe and run that to the gauge.
I'm running a VDO sender unit at the moment to a generic water temp sensor, so I shouldn't have any issues. I only have the Mp9 system running the engine, everything else is a mix match of various brands and makes.

I'll find out this weekend I guess.
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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by splitfan »

flatfourfan wrote:
splitfan wrote:Gary the mp9 system uses a dif sender for water temp and im pretty sure it wont be compatible with you gauge , I would just plumb a VDO sender into a waterpipe and run that to the gauge.
I'm running a VDO sender unit at the moment to a generic water temp sensor, so I shouldn't have any issues. I only have the Mp9 system running the engine, everything else is a mix match of various brands and makes.

I'll find out this weekend I guess.
The four pin square sensor on the housing on the front of the head is the temp sens for mp9, I hope you have this connected as the control unit needs water temp to adjust fuel & timing ?
My biggest fear is that my wife sells my cars for what i told her they cost !!
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Re: Using a Porsche 912 oil gauge as a water temp gauge

Post by flatfourfan »

Yup, that's stock MP9, but I'm talking about the additional sensor that I have running out back.......I have an additional unit out back that comes from the return to the engine for my standalone temp gauge.

This is where the temp gauge sender goes.

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