71-72' 50hp Johnson Low Speed Needle Valve.....

[jbuote]

Howdy!

​I have a 50hp Engine I got in August last year.
​Got it to run after rebuilding carbs, but still won't start reliably. Seems to flood out quickly. (yes, quicker than normal.. LOL)
​I've checked everything else (spark, coils, crank speed etc...)
​I was thinking of replacing the low speed needle valves and seats. However, for the life of me I can't find the seats in any parts breakdown or diagram.
​The engine is either 71 or 72. (Sold to me as 72, but plate says 71. He had 2 and built this engine out of parts from both, but carb is the same for 71 and 72)

​Does this carb even have replaceable seats for the low speed needle valve? Is it built into the body and not replaceable?
​Can't imagine the plastic needle bearing deep in the body is the seat.. LOL
Needle valve looks fine, but it was the seat I was wondering about. Is it even worth replacing the needle valve if it looks good and there is no "Seat" proper?

​Thoughts?

 

[racerone]

What other trouble shooting has been done ?------Is choke solenoid adjusted properly ?------Does it start better if manual choke is used ?-----Are the battery and starter in good shape ?

 

[jbuote]

Hi Racerone,
​Yup.. I've adjusted the chokes, No it doesn't start any better with manual choke, and the battery is new, and the starter cranks just fine. Great shape there.. lol
​Even if it turns out to be a completely different problem, I'm still curious if there is a seat for the low speed needle valve. Seems odd if not.. haha!

 

[jimmbo]

There is no removable/replaceable seat for low speed needle, Why do you think it needs replacing? 45 yrs ago it was replaceable, by replacing the carb body.
Are the floats in good condition, and properly adjusted? Are the inlet valve seats properly gasketed and tight?
What is your starting protocol? Explain in detail

 

[jbuote]

Hey Jimmbo,
​Interesting about the "Seat".. Thanks!
​Floats are new. Did a carb rebuild (minus the needle valves). Float adjusted properly, new float needle and seat (That's what you meant by inlet seat?)
​As for starting procedure, it's new to me, so still figuring it out.

I'm at:
​prime fuel line bulb till firm, hold choke on (Electric), crank till signs of starting, release choke till starts...
​Sometimes it does start, but if not in first try or 2, it's flooded out and won't start..
​Problem could be my starting procedure so..... LOL

 

[F_R]

I don't see any mention that you are raising the fast idle lever on the remote control when starting the motor. It is important that you do that, if you expect it to start easy.

 

[jbuote]

Ah, yes F_R.... lol... I forgot about that... Just getting her ready for this season, so I'll keep you posted how it goes. I was initially (in this post) wondering about the needle valve and seat, and that's been answered.. However, I may end up with more questions as I progress with it! lol

​Thanks!!

 

[jbuote]

(sigh..)
To close this out, it ended up being a sheared flywheel key that prevented proper starting..
Long overdue I know..

Adding an ending to any open threads/topics I have.
Thanks to all!

 

[Joe Reeves]

Sheared key huh?... Tapers must be clean on both components (Flywheel & C/S)... Torque nut to 105 foot pounds. Failure to torque properly will result in a repeat performance.

 

[jbuote]

Hey Joe!

Yeah, cleaned them up and did torque to 105 back in April.. She is running strong still!!
Was just going through last night and adding an end to any open topics I started so they weren't left with no resolution..