fergycool
Well-Known Member
Hello,
I'm trying to understand why the temperature gauge on my Perkins 4.270 is not working.
The initial symptoms were that from the moment the engine was started the gauge showed 80degC and never moved. When turned off it went to the minimum.
I checked it according to the Nigel Calder's book. With the sender lead earthed to the engine block the gauge shows max deflection. With the lead just disconnected (open circuit) it shows min reading. I guessed it was the sender itself so I replaced that.
Now when I start the engine the needle moves slightly and after an 30 mins moves slightly more. However, it is nowhere near the first line of the gauge which is 40degC. I had an 6 hour run yesterday and the needle did not shift. However, I did check the temperature of the engine block with a infra red thermometer after three hours and it was only 36degC. With the other engine the needle stays between the 50degC and the 90degC mark which I assume is about 70degC and acceptable).
It's a completely different gauge to the other engine.
Have I got a too efficient cooling system (i.e. bad) on this engine (it has a calorifier attached) or more likely is the gauge broken or just incompatible with the sender?
I now realise that I should have checked the sender with some water of known temperature before reassembling it. However, I do not want to drain the engine block again if I can help it.
Thanks!
I'm trying to understand why the temperature gauge on my Perkins 4.270 is not working.
The initial symptoms were that from the moment the engine was started the gauge showed 80degC and never moved. When turned off it went to the minimum.
I checked it according to the Nigel Calder's book. With the sender lead earthed to the engine block the gauge shows max deflection. With the lead just disconnected (open circuit) it shows min reading. I guessed it was the sender itself so I replaced that.
Now when I start the engine the needle moves slightly and after an 30 mins moves slightly more. However, it is nowhere near the first line of the gauge which is 40degC. I had an 6 hour run yesterday and the needle did not shift. However, I did check the temperature of the engine block with a infra red thermometer after three hours and it was only 36degC. With the other engine the needle stays between the 50degC and the 90degC mark which I assume is about 70degC and acceptable).
It's a completely different gauge to the other engine.
Have I got a too efficient cooling system (i.e. bad) on this engine (it has a calorifier attached) or more likely is the gauge broken or just incompatible with the sender?
I now realise that I should have checked the sender with some water of known temperature before reassembling it. However, I do not want to drain the engine block again if I can help it.
Thanks!