With the mass cable from the sensor connected directly to the chassis, and the ignition on, the coolant temperature gauge should give maximum deflection. Which it did not. led me to the conclusion that my coolant temperature gauge was off by 25°F. So time to open up the dashboard
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I have driven my Spider some 400 kilometers already. I need to clock a total of 1000 km, after which I will take it back to Marc. We will do an oil and oil filter change and re-torque the headbolts. And hopefully, no more excessive oil usage!
There are a few other small jobs that needed some work. The most pressing one was the coolant temperature gauge on the dashboard. It was indicating about 25oF too low. This is an Italian Spider produced for the US market, so the speedo is in miles, the oil pressure is in psi, and the temperature is degrees Fahrenheit.
I knew the engine coolant was running at the correct temperature. Marc had replaced the thermostat when redoing the pistons and liners. I can check it in three different ways. The cylinder block is supposed to be at least 75°C.
It takes a bit of training and experience, but as a rule of thumb, up to about 65oC you can still put your fingers on it and hold them there. At 75- 80 °C you wont last more than 0,5 second. The cabin air heater is also a good indication. When it is set to full blast, again the hot air is too hot for your feet.
And more exactly, I also use my IR thermometer to check the temperatures. A small word of caution here. IR thermometers are notoriously unreliable or rather inaccurate on aluminium. And the Spider is an all aluminium cylinder block and valve cover.
I checked the resistance of the coolant sensor and concluded that the sensor appeared to be working correctly. With the mass cable from the sensor connected directly to the chassis, and the ignition on, the coolant temperature gauge should give maximum deflection. Which it did not, it was, again, some 25oF low.
Which led me to the conclusion that my coolant temperature gauge was off by 25°F. So time to open up the dashboard.
My Spider has one of these central Instrumentation clusters. All the instruments are in one cluster. The trickiest part is removing the bezel. Because it is made of plastic, and nearly forty years old, and you need to twist it to get it from underneath the cluster.
The instrument cluster is held in place by four simple screws. Undo them and you can pivot it sort of forward which provides, sort of, access to the four plugs at the rear of the instrumentation cluster.
Here is the complete "cluster" as it is known
Upside down to remove the bottom half which included the coolant gauge. Again, just four screws.
This is the top half of the cluster.
I placed that back into the instrument pod and hooked up the three respective connectors. The fourth connector is for the lower instrument part
Next I put an electric kettle inside a big plastic tub on top of the engine. Marc had lent me a new spare temperature sensor. I attached the sensor wire to the new spare sensor and connected the sensor body to the car chassis. So the input for the temperature gauge is now the new spare temperature sensor inside the kettle!
With the water in the kettle on the boil, I adjusted the needle of the temperature gauge to read 212°F (100 °C). You can adjust the position of the needle utilizing a small lever that protrudes right at the bottom of the gauge.
It's a bit fiddly and I had to redo it several times, but I got it right in the end!
Put everything back together again. Look at this a solid 175°F (80 °C) with the engine properly warmed up. Also, repeated long-term idling with all the fan and AC on, did not move the needle. Which also means the new thermostat is working well.
Another small job: When I had the soft top replaced, the whole frame was removed and powder coated. It looks great!. And I want to keep it like that. When you lower the soft top (and I always drive top down, sun, rain, sleek or snow) you have these special elastic bands that keep it pressed down. They hook onto the frame.
These hooks are bare metal and will damage the powder coating. So I wanted to cover them with something "rubbery". In the end I used bits of crimp hose.
Looks good, I will need to see how long they last. The reason for putting these elastic bands is to compress the top in the down position so they fabric has little room to rub against each other.
Next job is to open up the right door, by taking the door card off. You have seen me do this numerous times on the Spider and my other cars. There is some rattle that I can't pinpoint what is causing it. So I am going to open up the door.
Stay tuned.
Jeroen
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