Where did you get the 80 amp figure from?

I would expect flames or at minimum a blown fuse with over double the stated design current going down the cables.

The 80 Amp figure came by using a DC clamp ammeter. I also did a separate check by putting a 0.15 Ohm resistor in series and measuring the voltage across it. They still took 32 Amps and measured about 0.1 Ohms

They are difficult to get at so my measurements are always in the lot in situ

The engine is a Durotorque registration 54.

Thanks for replies to everyone

I guessed they might do so but the 80 Amps was the stable current. The meter takes a time to settle and I connected them straight to the battery with jump lead and the meter round that. Nothing has been changed in the way of filters. This simply started happening probably coinciding with the lower winter temperatures. It is kept in a garage so it doesn't see very low temperatures but when I visited my daughter at Christmas it was outside and covered with frost one morning. It spent a lot of time coughing but did start eventually.

Another clue may be that on two occasions it started up in a funny mode. It may have been on two cylinders but sounded more like one. I guess the ecu got screwed up and possibly went into the 2 cylinder mode that it's supposed to when it over heats

Thanks