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Discussion Starter #1
Ran a compression test tonight on my 66 I6 200. I would like some input on the results and a bad noise that I heard.

I warmed the engine up for up about 18 minutes. The entire time there was a wop-wop-wop, very slight, consistent, not getting louder. Made me think of something unbalanced spinning. At 18 minutes (yes I was timing it) I heard a slight whine/squeel (hard noise to describe, not quite like metal on metal, but similar). It took 3-5 seconds to realize that it was comming from Patience (my 66's name), not from outside the garage. I turned her off quickly, noting that in this time the temp gauge read slightly over middle of the guage. This noise got quite loud in the 8-10 seconds that I heard it. It didn't stop until the engine stopped spinning. This noise worries me quite abit.

I checked the upper rad. hose by feel and it was hot so I decided to run the compression test anyway (plus I expect I need a rebuild anyway). I followed the Ford Manual, removed the spark plugs, all equally black (but not oily), opened the throttle and choke plates fully and ran the test. I then shot 2-3 small squirts of 10w-40 down each cylender in turn and reran the test. Results are below, first column is "dry" test, second column is "wet" test

Cyl #1 154 175
Cyl #2 160 178
Cyl #3 156 174
Cyl #4 170 195
Cyl #5 165 188
Cyl #6 170 198

Looking for input, on both the test and the sound. I realize this is not as specific as a leak down test, but I've never tried to revive a stored engine before.

Thanks for you help!!

2,109 Posts
Drain the oil into a clean pan. Then run the oil through a coffee filter. Cut the bottom off of a 2-liter coke bottle and put the filter in it. Your looking for metal in the oil. The noises you described could be a beararing going or something with the distributor. The fact that compression is good is a real good thing.

Another test is to remove the fan belts. Start the car and listen for the noise. if the noise stops making it without the fan belt it is something on the outside of the engine if it keeps making the noise it is on the inside of the engine. Remember you won't have a water pump so keep it under a few minutes.

When you did the compression test you should have looked at your plugs, i assume you saw nothing strange there.
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