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Old 07-29-2016, 07:20 PM   #19 (permalink)
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Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
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Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 53.56 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 61.98 mpg (US)

Fancy Metro - '14 Mitsubishi Mirage top spec
90 day: 58.72 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 66.29 mpg (US)
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engine check-up

I did a quick 'n' dirty compression "test" when I checked out the car in Montreal:

1) Got a baseline: I know the Flea has spec compression, so I put it in 1st gear on level ground and released the parking brake.

With the door open, I pushed against the A-pillar until the car moved a little. I had to push pretty hard -- hard enough that I found I was holding my breath to make it lurch through each compression stroke.

3) A few hours later in Montreal, I repeated the procedure on the Y2k Metro. It seemed like a similar (high) amount of effort, which I did 3 times (once for each cylinder), so I decided it must not have bad compression. Also it seemed to start up quickly, and had "normal" power (for a Metro).

Is that a valid way to check compression? I dunno.

But a pilot friend says he has used a similar technique to check propeller airplane engines.

Actual compression test done this aft with a proper gauge... and it's great:

1st set: 205 / 185 / 210
2nd set: 210 / 195 / 215


(As predicted by the the DIY method and the stack of maintenance/repair receipts in the glove box that includes lots of oil change bills.)

Also, I discovered one of the spark plugs was loose! And by loose I do not mean "finger tight" - it was loose. But all were otherwise healthy looking, and are only a few years old.

The distributor cap & rotor were disasters though: burnt/carbonized electrodes like you wouldn't believe. Last changed in 2003, if the stack of receipts is accurate. So I cleaned up the rotor, put on a new cap and it now it runs smoother & quieter (the tightened up spark plug might have helped too).

So now I'm even happier with this purchase.
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