Someone knows fersure. Sneezing and idle screw does little

[arto13]

Hi, this is my first boat. 1988 25hp johnson.
She starts right up, never a problem.
BUT, she sneezes and turning the idle screw helps just a little bit.
When i tried running her on a lake she just wouldnt go faster and was very very unsteady sppeed.
I cleaned carb, new fuel pump, new fuel tank lines, AND new fuel pump and all fuel lines. Im not a hundred percent sure that my replacement lines are EXACTLY tje same sizes as before but i tjink they are.
The fuel line attachment nipples were sometimes slightly different at each end for the same lines.
Help pleazzzzzz

 

[racerone]

Information is needed here.-----Post the results of a compression test.-----Does spark jump a gap of at least 3/8" ( 1 cm ) on both leads ?----Then again it might be as simple as the throttle plate opening too early.

 

[arto13]

Oh. I just assumed that because it starts so easily, tje spark is good.
I have to look up about the throttle plate in tje repair manual.
Thanks

 

[saltchuckmatt]

Excellent motor when set up correctly, setting them up correctly takes some time but very doable.

Best

 

[arto13]

Excellent motor when set up correctly, setting them up correctly takes some time but very doable.

Best

May i ask the basics of the setting up?

 

[saltchuckmatt]

I leave that to Racerone unless he doesn't respond.

 

[racerone]

I cannot see , hear or feel this motor.----Questions in post # 2 may seem silly to you !----Answering will only help you.----I have a bunch of these powerheads and they are easy to rebuild / repair or part out.-----Post picture of the STOP on that rod under the flywheel.----Picture with throttle at lowest idle.

 

[arto13]

I cannot see , hear or feel this motor.----Questions in post # 2 may seem silly to you !----Answering will only help you.----I have a bunch of these powerheads and they are easy to rebuild / repair or part out.-----Post picture of the STOP on that rod under the flywheel.----Picture with throttle at lowest idle.

Ok. I'll take a pic. I cannot honestly remmber a "STOP" under the flywheel. Ill give it a look.
I appreciate yhe help very much! I feel hopeful
I never had a boat and i looove fishing!

 

[saltchuckmatt]

Watch this for another clue.

 

[saltchuckmatt]

I love fishing too!

 

[arto13]

Watch this for another clue.

Good news is that I cleaned the spark plug wire connections and she ran fantastically in higher rpm's!! But, she does snort some when in low rpm's and warming up. but after warming up, in low rpm's, she still snorts but only a little.

I don't think the thermostat works. The "pee" never is more than warm. I live in warm Tampa Bay.
As per video, my carb butterfly starts to open at the correct spot which is between the 2 marks

 

[arto13]

I cannot see , hear or feel this motor.----Questions in post # 2 may seem silly to you !----Answering will only help you.----I have a bunch of these powerheads and they are easy to rebuild / repair or part out.-----Post picture of the STOP on that rod under the flywheel.----Picture with throttle at lowest idle.

Good news is that I cleaned the spark plug wire connections and she ran fantastically in higher rpm's!! But, she does snort some when in low rpm's and warming up. but after warming up, in low rpm's, she still snorts but only a little.

I don't think the thermostat works. The "pee" never is more than warm. I live in warm Tampa Bay. My mechanic buddy thinks the thermostat doesn't matter in Tampa warmth.
As per video, my carb butterfly starts to open at the correct spot which is between the 2 marks

 

[cyclops222]

A defective thermostat WILL WILL drive you crazy with rough idle and bogging down in low speed drive. Pull the spark plugs . They should look brand new. Are they the CORRECT ones in a specification check ? You will need a GAPPING tool to check the gap & possible readjust ...ONLY the thick bent over ground part.
What TYPE 2 stroke oil did you buy ? 2 types are available.... Water cooled engines or AIR COOLED engines. Used in chainsaws & weed wackers...... READ the label to see which 1 you have.
I went in circles with a gallon of ...AIR COOLED 2 stroke oil. Fouled up plugs in 1 day. Check carefully what type you have and the correct sparkplug gap.
What fuel to oil ratio are you using.
Damaged Reed Leafs inside the engine could cause sneezing but not affect W O T running.

 

[saltchuckmatt]

Ooooo, poop.

This one does not respect the force. Let yourself go....find the two words, then find the service bulletin about the two marks.

Joy will come.

I wonder if joy is "Hot"

Is it a cough/sneeze? Or does it fall on its face for a second as you pull away? (That's a hint)

 

[racerone]

Water from the pee stream does NOT circulate through the block.------It should never be hot or even warm.

 

[arto13]

Ooooo, poop.

This one does not respect the force. Let yourself go....find the two words, then find the service bulletin about the two marks.

Joy will come.

I wonder if joy is "Hot"

Is it a cough/sneeze? Or does it fall on its face for a second as you pull away? (That's a hint)

Love it

 

[arto13]

A defective thermostat WILL WILL drive you crazy with rough idle and bogging down in low speed drive. Pull the spark plugs . They should look brand new. Are they the CORRECT ones in a specification check ? You will need a GAPPING tool to check the gap & possible readjust ...ONLY the thick bent over ground part.
What TYPE 2 stroke oil did you buy ? 2 types are available.... Water cooled engines or AIR COOLED engines. Used in chainsaws & weed wackers...... READ the label to see which 1 you have.
I went in circles with a gallon of ...AIR COOLED 2 stroke oil. Fouled up plugs in 1 day. Check carefully what type you have and the correct sparkplug gap.
What fuel to oil ratio are you using.
Damaged Reed Leafs inside the engine could cause sneezing but not affect W O T running.

My mechanic buddy says not thermostat but when i let go and feel the Force i feel thermostat dissonance.
Correct plugs: i use manual specs. I gapped them(.03 or .028, forgot which).
I use Johnson/evinrude 2 stroke oil, 50:1.

 

[arto13]

Love it

Oh oh oh.. "service bulletin" i will search that

 

[saltchuckmatt]

Get a book....a good book.

 

[arto13]

Aha!!!!! Oboatwan.
I think i got it!!