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Stock Compression
- Thread starter jpass
- Start date
Speedling
Jetboaters Admiral
- Messages
- 5,152
- Reaction score
- 4,365
- Points
- 432
- Location
- Cedar Lake, IN
- Boat Make
- Yamaha
- Year
- 2008
- Boat Model
- SS
- Boat Length
- 21
Believe so. Lots of variables make that a ballpark. Do they all read within a few psi of each other?
- Messages
- 5,996
- Reaction score
- 5,447
- Points
- 452
- Location
- Florida
- Boat Make
- Yamaha
- Year
- 2021
- Boat Model
- Other
- Boat Length
- Other
I believe 165 is more like it but you could be getting a bad reading or have a bad gauge , it is difficult to get a good reading without the correct fitting to go down where the plugs sit
jpass
Jet Boat Addict
- Messages
- 138
- Reaction score
- 105
- Points
- 112
- Location
- Orlando
- Boat Make
- SeaDoo
- Year
- 2012
- Boat Model
- Challenger
- Boat Length
- 21
That's what the dealer said. I can always test myself.
Is there anything special I need to do aside from the normal procedure (warm motor, remove all plugs, disconnect coils, start, WOT)?
Is there anything special I need to do aside from the normal procedure (warm motor, remove all plugs, disconnect coils, start, WOT)?
- Messages
- 5,996
- Reaction score
- 5,447
- Points
- 452
- Location
- Florida
- Boat Make
- Yamaha
- Year
- 2021
- Boat Model
- Other
- Boat Length
- Other
nope that covers it
- Messages
- 5,996
- Reaction score
- 5,447
- Points
- 452
- Location
- Florida
- Boat Make
- Yamaha
- Year
- 2021
- Boat Model
- Other
- Boat Length
- Other
why are you concerned about your compression?
if you tell me the year and the symptom I may be able to help point you in the correct direction I had 2 of those for several years
if you tell me the year and the symptom I may be able to help point you in the correct direction I had 2 of those for several years
Last edited:
jpass
Jet Boat Addict
- Messages
- 138
- Reaction score
- 105
- Points
- 112
- Location
- Orlando
- Boat Make
- SeaDoo
- Year
- 2012
- Boat Model
- Challenger
- Boat Length
- 21
I'm not too concerned about compression. I was just questioning what stock was considering we just purchased it and the dealer said she ran 120 in all 6 cylonders.
Our V8 351 Windsor showed 150-155 between all 8 cylinders with 1820 hours on the 23 year old girl. Brand new motor has 160, so she was in great shape.
I had no idea where the compression should have been on our new boat and wanted to know what stock compression should be.
We only ran her twice and she seems to run just fine.
Our V8 351 Windsor showed 150-155 between all 8 cylinders with 1820 hours on the 23 year old girl. Brand new motor has 160, so she was in great shape.
I had no idea where the compression should have been on our new boat and wanted to know what stock compression should be.
We only ran her twice and she seems to run just fine.
- Messages
- 5,996
- Reaction score
- 5,447
- Points
- 452
- Location
- Florida
- Boat Make
- Yamaha
- Year
- 2021
- Boat Model
- Other
- Boat Length
- Other
ok so no problem means don't worry about it they just did not do the compression check correctly. I have seen the 4 tec engines hit upward to 180 psi if all read the same no worries.
