Boat Lost Speed

[DodgeRamWax]

Hello all! New to Bass Resource and seeing if anybody has any suggestions. I was fishing a little lake with my 20 foot stratos and it was pretty weedy. Anyways I left my motor down while trolling around fishing and then when I started it an alarm started going off. Took it to the shop and they said it was my oxygen sensor. They unplugged it and said I didn't really need it anyway. My boat use to top off at around 68 MPH and now I'm only getting 61-63 MPH. I put premium gas in it and use Stabil Every time I put gas in it. Replaced the spark plugs this past year is the only other thing I have done.  Anybody have any suggestions on why I lost my MPH or how to fix it would be GREATLY appreciated!

 

Thanks Guys

 

2000 - 20 SS Stratos with a 225hp Johnson

[tomustang]

Do Johnsons call for premium gas or just regular? if regular you shouldnt mess with octane levels that are recommended from the maker.

[tomustang]

Did you run it right before you put the motor down and get 68?

How does the prop look?

I would doubt the effectiveness of your shop if you disconnect items instead of fix them.

If the sensor is anything like a cars sensor then it reads exhaust gas and makes adjustments to the fuel system for running. I would start at replacing that first

[Way2slow]

What's the RPM doing?

I hate to say this, but you have thrown me a curve ball. You said it's a 2000 year model, 225 Johnson, which means it should be a two stroke. My problem is I have always thought I knew that motor pretty dang good and I've never known one to have an oxygen sensor. I'm gonna have to do a little research on that one.

As for your loss of speed, it would help if there was a before and after RPM.

What type and pitch prop are you running?

[gardnerjigman]

I'd replace the sensor that you "don't need". The motor will run with it gone, but won't make the adjustments needed as stated above. 

[FlipSide]

Hello all! New to Bass Resource and seeing if anybody has any suggestions. I was fishing a little lake with my 20 foot stratos and it was pretty weedy. Anyways I left my motor down while trolling around fishing and then when I started it an alarm started going off. Took it to the shop and they said it was my oxygen sensor. They unplugged it and said I didn't really need it anyway. My boat use to top off at around 68 MPH and now I'm only getting 61-63 MPH. I put premium gas in it and use Stabil Every time I put gas in it. Replaced the spark plugs this past year is the only other thing I have done.  Anybody have any suggestions on why I lost my MPH or how to fix it would be GREATLY appreciated!

 

Thanks Guys

 

2000 - 20 SS Stratos with a 225hp Johnson

 

[DodgeRamWax]

Thanks for the tips guys. Finally off for a couple months of tourney fishing and took it to the shop. They are replacing the sensor and apparently my FUEL pump is shot is why I lost speed and hull shot.  Thanks again for all the advice!

[tomustang]

Glad it worked out

[Bluebasser86]

Thanks for the tips guys. Finally off for a couple months of tourney fishing and took it to the shop. They are replacing the sensor and apparently my FUEL pump is shot is why I lost speed and hull shot.  Thanks again for all the advice!

We need to get out and fish sometime man, been way too long! 

[Way2slow]

I still want to know how the heck they are replacing an O2 sensor that motor doesn't have. Sounds like somebody is getting the royal treatment.

[Canyon explorer]

I would have the sensor replaced. I would also use regular fuel ( without ethanol) if you can find it. Premium fuel only enhances performance if the engine is tuned( speced)for it. Also keep in mind a boat usually slow down as the water warms. my 193 Champion was always 3 MPH faster in winter.