A Radiator Story - Part 2

[ICEpeter]

Continuing with part 2 of first post:

16 - Radiator assembly with fan and fan drive

17 - Detail of temperature sensor installed in flange. Sensor dimensions: Dia. 1/8 inch by 9/16 inch long, ss 304

18 - Lot temperature sensors made, 10 sensors total - 8 to be used, two spares. Used to monitor water in / out, oil temperature, ignition coil temperature monitoring

19 - PDF with drawing of radiator assembly showing general dimensions and coolant flow zig / zag routing
View attachment Radiator Assembly.pdf

After finishing the assembly using the newly made upper radiator part, it was again air pressure tested, this time with 30 PSIG, and submerged in water and showed no leaks. Since the radiator and cooling system is not pressurized in operation, I don't expect any long term leaks. Have to be lucky sometimes.

Thank you for watching.

Peter J.

 

[Wizard69]

After finishing the assembly using the newly made upper radiator part, it was again air pressure tested, this time with 30 PSIG, and submerged in water and showed no leaks. Since the radiator and cooling system is not pressurized in operation, I don't expect any long term leaks. Have to be lucky sometimes.

Thank you for watching.

Peter J.

I was always under the impression that pressurization of the radiator increases its efficiency. I could be wrong as I'm not strong on some engineering associated with engines. Probably doesn't really matter as long as your engine is kept properly cooled.

By the way thanks for the posts and great pictures. I think the word here is inspirational.

 

[ICEpeter]

Hello Wizzard,
If I remember correctly, when you pressurize a radiator it will result in a higher boiling temperature of the coolant (water) and you could run the engine at a higher operating temperature. At ambient (sea level) pressure your water would boil at 212 F and generate a lot of steam, hindering efficient cooling and requires to run the engine at a lower operating temperature.

You may have heard that when you boil water at a high elevation that the water starts boiling at a lower temperature, just the reverse effect of water boiling at higher temperature under pressure.

If I run into a cooling issue I may consider a slight modification of the expansion tank that would let the engine radiator run at pressure of not exceeding 14 PSIG by incorporating a pressure relieve valve and sealing the expansion tank. Once the engine runs, I will get my clue as to what to do or not. Thank you for your interest and feed back.

Peter J.

 

[ICEpeter]

Hello all,
It may be of interest to others who are considering the incorporation of temperature sensors and a temperature monitoring system to find out more details about how I went about it and what hardware I used in my system.

Since I was unable to find suitable small size temperature sensors, I set out and build my own. For the housing I used dia. 1/8 inch, stainless steel 304, by 9/16 inch long. The housing was drilled out with a 3/32 inch drill bit leaving a wall thickness of about 13 thou for a good heat transfer. The Thermistor element I used measured 0.095 inch across and fits perfect in the drilled hole. Connecting the thermistor element wires to the connecting cable hair thin wires was a bit tedious and required the use of a Lupe. Got it done and used very small isolation tape bits to separate the two wires. (The connecting cable used was liberated from my sons old ear phone set)
After soldering the elements to the connecting cable I filled the drilled cavity with Loctite Superflex Clear RTV silicone, rated for use of up to 400 F temperature and is non conducting. The thermistor element was lightly coated with the silicone prior to inserting the whole assembly into the cavity. Both the cable and the metal sensor part were restrained in a fixture while curing to prevent the cable from slipping out.

After curing I tested all 10 sensors made and they all worked perfect, displaying identical temperatures at testing.

Now, having mentioned the testing and needing to run the engine down the road, the engine does require a control panel providing the ignition power and power for all other auxiliary functions. I had a stainless steel enclosure in my collected parts storage, suitable to be used as a control panel for powering the engine, etc.
The resulting control panel is depicted in the attached pictures and has the following features:

- Display of the main power voltage source, which is a 6 volt 7AH gel cell battery
- Display of the aux power voltage of 12 VDC. The 12 VDC is generated by using a small DC/DC step up converter
- Display of the four temperatures being monitored using the temp sensors. Selecting the various temperature for monitoring is accomplished with a four position selector switch.
- Incorporation of patch wires which allows the charging of the 6 VDC battery without removing the battery or opening the panel for access to the battery.
- Incorporation of selector rocker switches in the 6 VDC and 12 VDC circuits that allow switching between reading the voltage or current.

The accompanying pictures show what I described above in more detail and are in sequential order described as follows:

1 -Front of control panel, powered up and displaying 6 VDC / 12 VDC and temperature

2 - Close up of 12 VDC showing converted voltage, converted from 6 VDC to 12 VDC

3 - Close up of 6 VDC showing source battery voltage

4 - Close up of temperature display with sensor laying across in front of display - showing room temperature. The displayed temperature is accurate within 1 degree F.

5 - Close up of 12 VDC display - switched to display current. Shows a current draw of 0.2 AMP of the cooling fan used to cool the ignition coil which is installed in an aluminum heat sink in the display base.

6 - Plug attachment on display base connecting the base to the control panel with four plug in points for the incorporated temperature sensors

7 - Overview of the cable connection between the engine display base and the control panel

8 - Control panel interior with 6 VDC 7 Ah battery and DC /DC converter

9 - Control panel interior wiring

10 - Honeywell Thermistor data sheet

11 - Loctite data sheet

12 - Lascar voltage / current display unit data sheet

13 - Lascar voltage / current display unit data sheet, page 2

14 - Lascar temperature display unit data sheet

15 - Lascar temperature display unit data sheet, page 2



Thank you for watching.

Peter J.