Mazda Engines-interchangeable

I have a 99 Mazda Protege 1.8 liter 16 valve, and the engine had a valve making a noise and the car stopped-engine probs. I ran an add for a replacement engine and a guy stated that he thought that his (98 626 2.0 liter 16 valve) motor would work. His Mazda has a bad transmission. Would the motor from the 626 interchange w/the protege or would the protege transmission interchange w/the 626 car? The 626 is for sale for 400. w/title. I pd approx 3200.00 for the mazda and it had 145k miles on it. I just had 1200.00 worth of tires and suspension work repaired on the car. I did not change the oil for approx 40k miles-is that why the engine went out? I know I am asking several things but I need some help/advice in Bammy…Thx, Jack Ward

Hi, Jack Ward here again (aka lockstar). I meant to say the Protege had approx 110k miles when I bought it maybe 3 or 4 yrs ago and it now has approx 150k miles w/a bad motor now.

Thx, Jack Ward in Bammy

Why not buy the car and have the transmission fixed? Because a running car would cost the same. I would not try to use the other engine. It won’t work out.