Compression test what ya think?

evening folks!

just done test on my 51 THOR, what you experts think of the results? should i worry?


7 150 160 8
5 150 150 6
3 150 160 4
1 140 150 2

any remarks welcomed

Dave

Wet or dry? Number 1 would be a worry. Depends if it's HC or LC for rest.

Did it the way I always have. Plugs out, tester in and 7 cranks. Not sure which way that is, but to me it's normal.

leakdowm test is the way to go

what was reason for doing the test?

sas1810 said:

Did it the way I always have. Plugs out, tester in and 7 cranks. Not sure which way that is, but to me it's normal.

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Plugs out, throttle wide open. Crank each cylinder for same amount of time.
Note pressures. Repeat with a squirt of oil in cylinder. For any cylinders with low readings. Like your number one. If compression rises duff rings if it stays the same duff valves.

jamesmartin said:

what was reason for doing the test?

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Had a bit of random missing lately. Just wanted to see if anything was untoward in that area. Been told it might of been cam starting to wear, coil pack, or leaking cyl. Leak can be ruled out as not lost a drop in almost a year of ownership. Cam could of been poss due to mileage, 128k, but results look ok apart from cyl 1.

And the oil filler cap is as clean as a whistle. Not a drop of anything in it. Does look as though it has had heads off before, rocker cover gkts look almost new.