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Well…….. compression is almost identical across all cylinders
Will re-run compression tests tomorrow. What I noticed once I took out the cap with the wires still attached to it, some wires were longer then others.Did the gauge you used have a face similar to this?
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The outer ring is in PSI. (Pounds per Square Inch)
The inner ring is the resulting compression ratio. There are some variables at
play, but what we normally see on a stock motor is 120-150 psi, which translates
to an ~8:1 to 10:1 mechanical compression ratio.
The readings you have would translate to a ~5:1 compression, which is either a bad
test result or an engine that would barely run? Since you are driving your vehicle,
I'm thinking that we need to rerun the test?
Being able to run a compression test is a valuable skill, but there is a
little 'technique' required to get a reliable reading. Over HERE we were
talking another member through the test process, so instead of typing
it all in twice if you could go check that out and compare it against what
you did, then no doubt we're get this all sorted out.
NOTE: One thing I didn't state in the list of things to do in the other
thread was to make sure and take the reading after 5 compression cycles.
On a healthy cylinder I would expect the readings to climb like this:
1st) 80
2nd) 110
3rd) 125
4th) 133
5th) 140
NOTE: These are made up numbers, but this illustrates how the needle will jump with
every compression event. Important: If the gauge drops backwards after
each compression event, then there's a leak somewhere (schrader valve?) that
you must address before proceeding.
Again, good news that they are all the same and that #4 isn't a dead cylinder.
And once you report back with either repeated or more normal results, then
we can discuss the plug coloring that's showing.
Repeating tests can be a bit tedious, but we need trustworthy results in order
to provide the accurate guidance you deserve.
Best of luck --
No. Inner ring is pressure measured in Kilopascals (kPa) x 100.Did the gauge you used have a face similar to this?
You must be registered for see images attach
The outer ring is in PSI. (Pounds per Square Inch)
The inner ring is the resulting compression ratio.
I agree. "60 psi" is WAY too low to be accurate, unless that engine is REALLY unhealthy, or your elevation is about as high as the Space Station. I watched a 400 "Cleveland" with one cylinder at 50 psi. That cylinder was dead at idle but ran--kind of--at higher power levels.I'm thinking that we need to rerun the test?
Yes.Important: If the gauge drops backwards after each compression event, then there's a leak somewhere (schrader valve?) that you must address before proceeding.
Yes.we need trustworthy results in order to provide the accurate guidance you deserve.
Huh.Gauge: