HELP 4trak turbo problem 1986 2.8td


hi, just bought a 86 creg 2.8td4trak, turbo light comes on when ignition key is turned on start up, then goes out and does not come back on when i exceed 2500 revs, is the turbo working ?, or is there a way of testing it any help is much appreciated, also temp guage not working but all other guages an lights ok,

Turbo probs

Hi. the turbo light should come on with the egnition switch on and go out when at tickover. at around 1200 rpm under load the turbo light should come on and u will feel the power come in. the light is driven by a pressure transducer in the manifold prior do the over boost dump valve. to see if the turbo is working, attach a pressure gauge to the blanking plug and read the changes. alternatively u can take off the hose from the filter to the turbo and see if it goes round while the engine is running.It should be a loud whine. Do not poke yourself or anything else in there while it is running.

john s