I have a '97 Explorer XLT with 90K. Runs great except that engine smokes after a steep hill
climb. Does anyone know what this could be? I've had my mechanic check it out on the same day I experienced this, but he could not find a problem.

Nancy Schrock
Mill Valley, CA

 

90K miles, my guess is that the 2 back cylinders are burning the oil. I bet the old girl uses a little bit of oil under normal driving conditions. I think that the oil in the cylinder heads runs toward the back as you go up hill. This oil goes over the valve seal and into the cylinder. The valve seal are probably just old and hard, and the valve guide wearn. If this is the cause, they can be replaced without having to remove the cylinder heads. Just my guess

 

Easy way to fing out , just jack the front end up an run her a spell an see whats happen. Had one once that the oil drain back holes in the head were plugged except the far rear ones.--- Also noted that when you did a oil change it would run outta the valve cover as you refilled the engine with oil-----------

 

You have too much oil in it! Check oil level. If over the 2nd hole in the dipstick, drain oil and change filter. add 5 qts max. If oil level comes up again, you have a cylinder head gasket leaking water into oil.