aluminum radiator question

[Ruscal]

Originally Posted by Kaptain Kadian

I have 2 temperature probes, one that is threaded and one that is inserted into the radiator fins. I want to run the temperature probe for the fan relay in the radiator and not the intake or heads. My threaded port on my radiator is 1/8 and my threaded port is 3/8. I bought an adapter to fit the 3/8 probe into the 1/8 port, but am concerned about it getting an accurate reading with the adapter on it. Anyone else ram an adapter like this?

I am using a Derale radiator probe that has been adapted to 3/8npt. I put transistor heat sink compound on the sender/probe joint, and lightly tightened it down. (8-32 brass threads) Go easy!
Derale tech said to put the sender on the bottom radiator outlet. (coolest point)
They also said the radiator probe sometimes does not work well with aluminum radiator cores with large tubes. I decided to go with a wet sender to avoid those problems. I purchased an inline radiator hose sender adaptor. It is aluminum with 1 1/2" double barb and 1/8" NPT hole and a grounding screw terminal.
I am using the Derale PWM fan controller which has an adjustable turn on temperature set point. Right now I am fiddling with the settings to see how it reacts. It comes on at 195F, fans start slowly and ramp up to any speed to bring the temp down. Mine, as the settings are now will bring the temp to 175F at the lower radiator outlet and hold it there. The fans seem to only need to run at slower speeds to maintain that temp. They are very quiet. as they only speed up as necessary. My truck has a 180 T'stat.
The truck is still in the build stage, so no desert tests yet.
Russ

[Kaptain Kadian]

Where did you get the inline radiator hose sender adapter?

[Fitz]

Originally Posted by Kaptain Kadian

Where did you get the inline radiator hose sender adapter?

Summit racing has a wide selection of diameters and fittings for almost any temp sensor size.

[hamjet]

I put mine here, it works fine..

[Ruscal]

Originally Posted by Kaptain Kadian

Where did you get the inline radiator hose sender adapter?

I found one on ebay. http://www.ebay.com/itm/381393834879

It had a 1/8 NPT sender hole and I needed a 3/8 NPT, so I had to drill and tap it. The manufacturer crowded the ground lug hole too close to the sender hole. I had to offset the new bore for the 3/8 tap to increase the space. Luckily I have a Bridgeport which made it easy. Most manufacturers of these parts anodize them for corrosion resistance and cosmetics, but it adds resistance to electrical circuits. Re-cutting my threads eliminated that problem. Both sender and ground thread were re-tapped.
Russ

[Kaptain Kadian]

Originally Posted by Ruscal

I found one on ebay. http://www.ebay.com/itm/381393834879

It had a 1/8 NPT sender hole and I needed a 3/8 NPT, so I had to drill and tap it. The manufacturer crowded the ground lug hole too close to the sender hole. I had to offset the new bore for the 3/8 tap to increase the space. Luckily I have a Bridgeport which made it easy. Most manufacturers of these parts anodize them for corrosion resistance and cosmetics, but it adds resistance to electrical circuits. Re-cutting my threads eliminated that problem. Both sender and ground thread were re-tapped.
Russ

Where did you install the inline adapter?

['68 Newtricks]

Coolant flows from the bottom to the top. The T-stat holds the water in the engine so it can pick up as much heat from it, regulating how fast/slow the coolant flows. It is also the second hottest position you can put a sensor. (first being the head) It is an accurate spot. The fans will come on to cool the incoming coolant, since the temperature of the coolant already in the radiator isn't cutting it. It's just more precise reading. Plus, if it's stupid cold outside or you have snow/rain coming though to hit the sensor in the radiator, well that will affect cooling.


Pick a good temp for the sensor and put it in the engine, your choice of where. My 400sb runs warm, so I'm 205 on/185 off in the summer. My fans can't cool it any more than 185. In the winter it's 200/180. My FAST system allows adjustment.

[biketopia]

Originally Posted by '68 Newtricks

Coolant flows from the bottom to the top. The T-stat holds the water in the engine so it can pick up as much heat from it, regulating how fast/slow the coolant flows. It is also the second hottest position you can put a sensor. (first being the head) It is an accurate spot. The fans will come on to cool the incoming coolant, since the temperature of the coolant already in the radiator isn't cutting it. It's just more precise reading. Plus, if it's stupid cold outside or you have snow/rain coming though to hit the sensor in the radiator, well that will affect cooling.


Pick a good temp for the sensor and put it in the engine, your choice of where. My 400sb runs warm, so I'm 205 on/185 off in the summer. My fans can't cool it any more than 185. In the winter it's 200/180. My FAST system allows adjustment.

You goto that backwards my friend. The thermostat controls how much hot coolant goes to the radiator and then flows top down. Heat rises remember.

['68 Newtricks]

saying the same thing
I'm talking about the flow in the engine

[Ruscal]

Originally Posted by Kaptain Kadian

Where did you install the inline adapter?

I cut the bottom radiator hose about 5" from the radiator. Derale tech said that is where it should be for their PWM setup. The PWM is adjustable, so you can set the temp where you want. It is different than using a fixed sender that turns on at only one temp and the fans turn full speed always.
Russ

[biketopia]

Originally Posted by biketopia

You goto that backwards my friend. The thermostat controls how much hot coolant goes to the radiator and then flows top down. Heat rises remember.

My bad I was really tired when I read that and responded.

[Kaptain Kadian]

Originally Posted by Ruscal

I cut the bottom radiator hose about 5" from the radiator. Derale tech said that is where it should be for their PWM setup. The PWM is adjustable, so you can set the temp where you want. It is different than using a fixed sender that turns on at only one temp and the fans turn full speed always.
Russ

Thanks for the help. I got one on order, should be here by the end of the week. Did you have to drain your radiator to install it?