Where to tap in Coolant System for Gauge

[Doakster]

Anyone have the best idea for where to tap in to the coolant system for a gauge sender.

The only place i see is the sensor that is drilled into the trans side of the head. Anyone know what thread size it is? I was thinking of teeing off that sensor.

I also don't see how it would be possible to tap in to the coolant "out" line on the head since there is no threaded connections.

Any thoughts?

[410]

that sensor on the transmission side is an oil pressure switch. 

[Vincent Waldon]

Best bet is to find a head outlet manifold with an extra sensor port.

Both the front and driver's side coolant outlets come in none/single/dual port configurations, depending on region, A/C, etc.  Sounds like you have one without any port, which suggests your other one is a dual.   Swap out a single for your non-port manifold and  away you go.  In your case you probably don't have A/C so look for a manifold from an A/C equipped car.

[Doakster]

My car does in fact have AC.

My front head outlet is a dual sensor port.

My driver side head outlet port is a single sensor port.

So it sounds like i need a duel port on the driver side head outlet. That being said how would an NPT sending unit adapt into the sensor port? Or would i some how use a VW sensor and adapt to it reads out on and aftermarket gauge?

[burn_your_money]

What is it exactly you want to install?

What you can do is get some brass fittings and splice into one of your coolant lines.

[Wayland]

I'm thinking about custom making a heater outlet flange so I can install a mechanical, capilliary-type temp gauge.

[Doakster]

What is it exactly you want to install?

What you can do is get some brass fittings and splice into one of your coolant lines.

I'm putting in a 3 gauge cluster, EGT, Boost and want a coolant temp for the third. I'm going with set of Isspro gauges, which come with an NPT sender to tap into the system. Really the easiest way would be to find somehow to tap into or adapt with the NPT sender.

As far as the brass fittings, are you talking about cutting the coolant outlet line on the head and installing a spacer of some sort that has a fitting on it?

[burn_your_money]

As far as the brass fittings, are you talking about cutting the coolant outlet line on the head and installing a spacer of some sort that has a fitting on it?

Yeah pretty much.

[Doakster]

As far as the brass fittings, are you talking about cutting the coolant outlet line on the head and installing a spacer of some sort that has a fitting on it?

Yeah pretty much.

So the next questions is, do you have a link to where i can fine something like that, i'm doing some searching myself.

[Doakster]

Bingo, just found all these.

http://www.jegs.com/p/Be-Cool-Radiators/Be-Cool-Fittings-Petcock-Tubes/744291/10002/-1

http://www.jegs.com/p/JEGS/JEGS-Inline-Radiator-Hose-Drain/1206363/10002/-1

http://www.jegs.com/p/Flex-a-lite/Flex-a-lite-In-Line-Hose-Adapters/1017700/10002/-1

Anyone know the internal diameter of the front or driver side coolant outlet hoses on the head?

[Wayland]

1" where they come out of the head I believe.

[Vincent Waldon]

Just checked ETKA:

single outlet driver-side flange tapped M10x1:   068 121 145K
triple outlet front coolant flange tapped M10x1: 068 121 133R
quad outlet front coolant flange tapped M10x1: 068 121 133C

[Vincent Waldon]

Just checked ETKA:

single outlet driver-side flange tapped M10x1:   068 121 145K
triple outlet front coolant flange tapped M10x1: 068 121 133R
quad outlet front coolant flange tapped M10x1: 068 121 133C

If there are any junkyards where you live you're very likely to find one of the above... cheap, and OEM with no extra cutting, clamps, leaks, etc.

[Vincent Waldon]

One last suggestion... because of the design of the VW cooling system the rad hoses are the last things to heat up and by definition will run cooler than the rest of the engine.. the head circulation circuit is probably a much more accurate place to find out how hot the engine is actually getting.

[Doakster]

Just checked ETKA:

 
triple outlet front coolant flange tapped M10x1: 068 121 133R

That one would probably work, is that the actual VW part number? And do you think the that the tapped M10 mean it has an M10 tapped port?