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2007 SX 230HO Compression Readings Good or Bad?
- Thread starter Brad3173
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Were the readings from warm or cold motors? They are pretty close together. https://jetboaters.net/threads/compression-test-results.16018/#post-275255
Cyl 2 many be low, but on both motors? Others will chime in soon.
Cyl 2 many be low, but on both motors? Others will chime in soon.
steveinmd
Jet Boat Addict
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Some questions I would have. Who did the testing? Has the boat sat for a long time before testing? When you have a cylinder that tests below 10% of the rest, typically the tester would drop a bit of oil in that cylinder and re test. If there is an improvement, the rings are suspect. No improvement then the upper cylinder is suspect (valves).
The rings can stick, causing a poor compression test. Putting it back in use will typically fix that.
The rings can stick, causing a poor compression test. Putting it back in use will typically fix that.
Bottom Bracket
Jet Boat Junkie
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good, do a leak down if you are worried.
Beachbummer
Jetboaters Admiral
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Leak down and water WOT run. Does it hit 10k on both?
Salt water boat? Or fresh water?
Best of luck!
Salt water boat? Or fresh water?
Best of luck!
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Did you have the throttle wide open when doing the test?
- Messages
- 5,979
- Reaction score
- 5,424
- Points
- 452
- Location
- Florida
- Boat Make
- Yamaha
- Year
- 2021
- Boat Model
- Other
- Boat Length
- Other
Also remember this " IF" the impeller is dragging in the pump it will dramatically reduce the r p m's when using the starter to crank the engine over. I have actually seen engines that refused to even turn over with a bad pump liner and if you spray some WD-40 inside the pump through the nozzle it will reduce that drag and may allow the engine to turn over faster and remember the throttle also needs to be open to allow air to rush into the engine while it is cranking .
