Where did you install your mechanical water temp sending unit?

[oz]

I plan to install an old but refurbished '69 center console into my '69 and add the Shelby gauge pod in place of the ash tray.
I am going to use a set of mechanical oil and water gauges. I want the gauges on the dash to function as well.

Where would you install the second water temp sending unit (the big bulky mechanical type)? Would you take out the dash gauge sending unit, put the new one in it's place and then find another place for it or not? I know there's a plugged bung on the water neck but I'm not sure if I would use this or not. If it makes a difference I have an Edelbrock Performer RPM intake - perhaps it has another bung for a sender in the water but I don't think so....?

As for the oil pressure sender, I plan to install a 'T' fitting at the end of the extension that was original to the engine. Does anyone know exactly what I'll need at the hardware store? Is it a 1/2" NPT thread or what? Since the senders are all MALE (corrected) threaded, I assume I'll need some couplers, etc... I can always take the sending units with me to the hardware store I guess.

Thanks!

 

[Tim65GT]

I'm pretty sure the oil pressure extention is 1/4" npt.

Since the senders are all female threaded, I assume I'll need some couplers, etc... I can always take the sending units with me to the hardware store I guess.

the senders are female thead? Never seen that before.

Yes, take them with you.

 

[Tim65GT]

It looks like the one by the waterneck would work for the mech water temp sender. I'd give it a try. How long is the sender?

 

[D.Hearne]

You can either "tee off" on the intake for a second sender but the fitting on the T-stat housing is too small for just about all sending units, save for some late models. The sender for my 89 Ranger's temp gauge fits the T-stat housing. That's how I did it in that. Electric sender in the T-stat housing and the mech sender and switch for the electric fans (radiator) are installed in a "Tee" fitting in the intake.

 

[ForceFed70]

Is there such a thing as a mechanical water temp guage? The only ones I've ever seen have had an electronic sender.

 

[D.Hearne]

Is there such a thing as a mechanical water temp guage? The only ones I've ever seen have had an electronic sender.

Yea, it's got a gas filled capillary metal tube that runs from the intake back to the gauge. They're a little harder to install but more accurate I think than an electric unit.

 

[ForceFed70]

Yea, it's got a gas filled capillary metal tube that runs from the intake back to the gauge. They're a little harder to install but more accurate I think than an electric unit.

Learn something new every day! Thanks D.Hearne.

 

[brin0357]

Mechanical gauges are the only way to go....

 

[Tim65GT]

Mechanical gauges are the only way to go....

Yeah, but if you've ever had the oil press line leak all over a new carpet...

Electrical gauges are the only way to go....

(plus you dont have to drill a large hole in the firewall for the temp sending unit)

 

[oz]

Thanks for the replies.

It appears that the hole in the water neck is larger than the one to the left side (where my electric sending unit is currently). My mechanical gauge came with some adapters that I think will work in the water neck. As for installing a 'tee', I want to avoid that because I wouldn't think that the water would be quite the same temperature as the water in the normal flow. I could be over analyzing it though.

Yea, the sender is MALE, not female... I must have been asleep when I typed the thread.

 

[ForceFed70]

Yeah, but if you've ever had the oil press line leak all over a new carpet...

Electrical gauges are the only way to go....

(plus you dont have to drill a large hole in the firewall for the temp sending unit)

Yeah. Been there done that. I also had the crappy nylon tube melt against my headers and dump oil all over the place. Luckily all the smoke let me know there was a problem before I ran the engine out of oil. So then I upgraded to a copper pressure line, but got distracted and forgot to tighten to back of guage. Soaked my brand new carpet in oil. That's when I finally decided to go electronic.

The electrical senders can be very acurate. It's the actual guage and needle that make for most of the error. When testing my junkyard GM temp sensor and my Megasquirt I did some testing by putting the sensor in a pot with some water, ice, and salt along with a traditional medical grade thermometer. The ice/salt brought the water temp down to 24*F. I then put everything on our stove and heated the pot up until the water started to boil. The traditional thermometer and the temperature read by my megasquirt were never more than *4 different. I was really pleased with how accurate it was.

 

[D.Hearne]

Thanks for the replies.
As for installing a 'tee', I want to avoid that because I wouldn't think that the water would be quite the same temperature as the water in the normal flow. I could be over analyzing it though..

You are over analyizing it. The temp difference in a Tee would be so slight, you couldn't measure it. Once the engine's up to temp, the intake and all it's parts are pretty much the same temp. If worried about looks, use brass or stainless fittings.