m271 compression test
#1
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C230 K Coupe (05)
m271 compression test
Hi guys, how does one check compression on an m271 engine and how/what/where to disconnect so that the car doesnt start.
thanks!
thanks!
#2
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All plugs out. Move coil on plug leads away from the plug holes. The AF ratio is unlikely to cause ignition but keep them out of where they can throw a spark to earth.
Apply WOT (wide open throttle). Place compression tester in each plug hole. Crank until max pressure is recorded on the gauge & record cylinder by cylinder. Do the dry first. Then give each cylinder 3 squirts of oil. Retest each cylinder & record.
Post dry & wet readings & post. We will comment.
Good luck!
Apply WOT (wide open throttle). Place compression tester in each plug hole. Crank until max pressure is recorded on the gauge & record cylinder by cylinder. Do the dry first. Then give each cylinder 3 squirts of oil. Retest each cylinder & record.
Post dry & wet readings & post. We will comment.
Good luck!
#3
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C230 K Coupe (05)
All plugs out. Move coil on plug leads away from the plug holes. The AF ratio is unlikely to cause ignition but keep them out of where they can throw a spark to earth.
Apply WOT (wide open throttle). Place compression tester in each plug hole. Crank until max pressure is recorded on the gauge & record cylinder by cylinder. Do the dry first. Then give each cylinder 3 squirts of oil. Retest each cylinder & record.
Post dry & wet readings & post. We will comment.
Good luck!
Apply WOT (wide open throttle). Place compression tester in each plug hole. Crank until max pressure is recorded on the gauge & record cylinder by cylinder. Do the dry first. Then give each cylinder 3 squirts of oil. Retest each cylinder & record.
Post dry & wet readings & post. We will comment.
Good luck!
#4
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C230 K Coupe (05)
Okay!
So I did a compression check a few moments ago and here are the results. Oh and i did only a dry test. Does that make this test any less useful?
1. 160psi
2. 155psi
3. 155-160psi
4. 160-165psi
What do you think?
TIA
G
So I did a compression check a few moments ago and here are the results. Oh and i did only a dry test. Does that make this test any less useful?
1. 160psi
2. 155psi
3. 155-160psi
4. 160-165psi
What do you think?
TIA
G
Last edited by hieracity; 10-28-2011 at 12:19 AM.
#7
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C230 K Coupe (05)
Thanks GMR!
Btw, do you guys know the exact torque spec for the spark plugs. Just got a torque wrench and next time i pull out the plugs (pretty soon to check for oil again), i want to use the correct torque spec. Thanks!
Is it 23 nM.....17 ftlbs?
Last edited by hieracity; 10-28-2011 at 12:02 PM.
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#10
All plugs out. Move coil on plug leads away from the plug holes. The AF ratio is unlikely to cause ignition but keep them out of where they can throw a spark to earth.
Apply WOT (wide open throttle). Place compression tester in each plug hole. Crank until max pressure is recorded on the gauge & record cylinder by cylinder. Do the dry first. Then give each cylinder 3 squirts of oil. Retest each cylinder & record.
Post dry & wet readings & post. We will comment.
Good luck!
Apply WOT (wide open throttle). Place compression tester in each plug hole. Crank until max pressure is recorded on the gauge & record cylinder by cylinder. Do the dry first. Then give each cylinder 3 squirts of oil. Retest each cylinder & record.
Post dry & wet readings & post. We will comment.
Good luck!
Thanks!!