intractable mystery solved 96 metro

96 4 cyl geo metro started dying, no power, etc. Checked everything I could think of, seemed to be fuel not getting thru injector. Lucky me I take care of 12 cars for a nonprofit and have a 97 geo everything is the same so started switching parts, injector first, brain, TPS, crank position sensor, distributor, nothing made a difference. Compression test redone with very different results, this turned out to be the clue. My geo expert who makes airplane engines out of geos told me to check for broken or missing teeth on timing belt to account for varied compression results. Timing belt was fine! But he told me that some geos with AC have been known to tear out the keyway on the crankshaft timing gear because of high speed cycling, corrected with a cushioned/rubberized outer pulley to reduce the instantaneous load at highway speed when the AC cuts in. Sure enough, the woodruff key was cleanly split (lucky again) without significant damage to the gear or shaft. He told me to fill the gap with metal-filing impregnated JB weld and a new key and I should be ok. Putting in new seals on crank and cam ends of course, and I'll be getting the new crank pulley as soon as I get the thing running again. Hope this is useful to someone, it was a real head scratcher .

Where did you find the rubber-dampened pulley? I just went through the same thing but I'd like to change the pulley to try to get a few more miles out of this engine before it ruins the crank.

All I did was disconnect the AC and remove all the dead weight. The AC sucks the life out of my 1.0L 5spd anyway. And this highspeed cycling crap just confirms my opinion that these cars shouldn't have been equipped with AC anyway.

Yeah it gets hot here in CA, but I would rather have power than creature comfort. Besides, with my windows rolled down I get to share all my good taste in music with my fellow drivers... :grinno:

Creature comforts get more important as time goes by.

Remember..It's not the heat, it's the humidity!!!!!

Try central Florida in the summertime...90 to 97 degrees F (sometimes higher) with a relative humidity of 90 to 95%----then throw a short rainshower in at 3pm and let it heat back up with nary a breeze------Feels like a sauna

Back before A/C was standard equipment, new cars and trucks without air would sit on the dealers' lots for months before they sold. About the only people that bought them were businesses...their employees were more likely to get out to the jobsite and their work done instead of sitting in the car or cruisin' their hours away!

Where did you find the rubber-dampened pulley? I just went through the same thing but I'd like to change the pulley to try to get a few more miles out of this engine before it ruins the crank.
sorry but I don't have it yet, my buddy who told me about the problem originally said he'd get me one before summer. I would imagine that later metros in junkyards would have it but I don't know when (or if) they started putting them in as original equipment.