QuestionSir,
Having multiple problems with my 1997 Discovery LSE. The engine tends to overheat every 7 or so days, which appears to be due to the fact that the coolant is disappearing. I replace the coolant, but it dissapears after a week -- a radiator flush was performed, and I am setting up a time to have it pressure tested. It was mentioned to me that replacing the radiator cap may be the solution -- any thoughts?
To compound the problem, however, the engine seems to periodically lose power when being driven at highway speeds; the engine will seem to be working fine, when the engine suddenly drops power off and slows a little -- this lasts only about 2 - 3 seconds before the problem goes away and the engine returns to life.
Finally, I had a problem with the engine backfiring and refusing to produce over 1,900 RPM after sitting for a weekend or more, usually in cold, wet conditions. I replaced the plugs and wires, and this seemed to solve the problem -- though I fear this may all be somehow related.
I am deeply concerned that the head gasket may be damaged, as the loss of power on the road and coolant seem to be symptoms of this. I am having the oil checked for the presence of coolant, which I understand will give me a better idea of what is wrong. Any thoughts you have will help, and thanks for providing a great service!
Michael
AnswerHi Michael,
Sir? John is good (no OBE attached to my name - yet.)
Your problem does read like a typical headgasket case. You don't see any coolant on your garage floor or driveway and yet it disappears? Usually boiled off by the heat of the engine, in the chambers or the sump.
Yes, a pressure test is the best means of verifying blown headgasket. Pressure testing each cylinder will help too.
The worst case is that a crack has developed in the engine block. This too can lead to coolant loss and loss of power BUT is far more expensive to repair than the headgasket.
Best of luck,
JohnMc
