Oil and Water Temperature Sensor Locations

[pirate]

I have a 3.4 V-6 Crate Motor that is going to be put into a sports car. I am going to use Auto Meter electric gauges for the oil pressure and water temperature. The water temp guage sensor/sending unit will be screwed into an Edlebrock intake manifold. I need a location to put a sending unit for the thermostat controled electric fan on the radiator. Should I screw that sensor into the tapped hole on the head or put it into the intake manifold also as there are additional tapped holes that can be used or will have to be plugged.

In addition to the Auto Meter oil pressure guage I would like to have a rather large idiot light to call may attension to low ouil pressure. It appears there is a tapped hole on the oil filter adapter that the sending unit for the guage can fit. I need an additional tapped hole for the idiot light. I have thought about using a pipe tee but am not sure I have enough clearence. There is a tapped and plugged hole just above what appears to be the by-pass so I don't know if that will work or not. Suggestion andor advise would be appreciated.

[AaronGTR]

What gen is the motor? Is it a 3400, or the older 3.4? Iron or aluminum heads?

I'm not as familiar with the older blocks, but on the newer blocks on the right side there is a threaded hole above and to the right of the hole for the dip stick. That hole is actually used for a factory pressure switch to turn on an idiot light in the factory gauge cluster. The switch closes at 5psi or below to close the circuit and turn the light on, but in my opinion by the time you are down to 5psi damage could already be done. A 15psi switch would be better if you could find one. I used a T-fitting and kept the factory switch and added a sender for an electric oil pressure gauge at that location. I don't know where the plug next to the oil filter opens up to, so don't know if that would be a good spot for a pressure reading or not.

[pirate]

It is the older 3.4 cast iron block and cast iron heads that was sold as a direct replacementb for the 2.8 V-6 aimed at the S-10 market. I did find a port on the side of the block that I think is a 1/4" NPT with a plug in it. It is above and to the right of the dip stick hole and about 3" in front of the bell housing mounting surface. My oil filter mounts horizonally so I am not sure there is enough room for a tee and both sensors but that would give me a location for the idiot light and the guage sender cound be mounted to the oil filter housing. I have a large "F" cast on the surface of the block if that helps you identify what block I have.

On the cast iron head 3.4 engine where is the factory water temperature sender located? Thanks!

[Daguse5853Z]

There are plugs in the side of the block that are routed into the coalant passages you could use. I've used that before when I had to mount a coolant sensor on my 3400. It was on the backside of the engine which would be the pass side if its mounted for RWD apps. Looks like the plug in your pic is what I'm talking about because I think there is a plug on both banks of the engine. You could always fill the engine up and check it at a later date. I changed mine in the car. You loose a little freeze but nothing serious.

Ummm also 96 beretta/corsicas use one coolant sensor with 3 wires you could maybe adapt to what you need to do. Thats what I did with my 96 S10 because I didnt have the room to use more then 2 sensors. I bought a thermostat switch to run my fans so that left me with 3 sensors, I combined the 2 factory sensors into 1 (96 3 wire) and put my thermostat switch in the drivers side head, the pass didnt have the room bc the dipstick was in the way (this a 4.3 engine im takling about now)

I'm looking at your picture and using the oil filter location as a reference (I'm assuming and you know what that means) but my oil filter is on the front of the engine which would be drivers side in a rwd app and that plug in your picture (not in the plug in the housing, the other plug) is where my oil pressure sensor is located. Sorry if I'm confusing more then helping lol.

So this is what I know for sure. The plug in the block on the rear of my 3400 block is a coolant passage and the plug on the front of my 3400 is for my oil pressure.

[Azrael]

Make sure there's enough clearance in those drain holes for the coolant sensor. I relocated my secondary sensor to a similar location on my 3100 and it made contact with a cylinder wall while installing. The sensor failed pretty quickly and the tip mushroomed out almost enough to keep me from removing it again.

I fixed it by using a male-male npt coupler and a female-female one. The sensor isn't directly in the coolant passage anymore but it still seems reasonably accurate.

[Daguse5853Z]

these are the colors to go to 1 coolant sensor. If the colors dont match then just match up the wire positions. This is viewed from the male enfd of the wiring harness. The bluish/greenish wire is the 1 wire temp sensor. Good luck


DERP!

[geoffinbc]

Use the hole in the corner of the head for the fan. This is a hot spot and will turn the fan on a bit early.

If this is a race car I would look into a Canton Racing remote filter adapter. This will allow you to move the filter and use a much larger filter which will help keep it cool, allow more flow and make service easier. It will also allow you to install temp and pressure sensors. If you don't want to go this route then use the factory filter adapter which has a 1/4" hole for the gauge. The one on the side of the oil filter pad will also work.