johnson 1969 55hp carb setting up

chris01803

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my johnson runs fine, but i can here a poping when open the throttle up,

on the carb, there are 3 injectors, with the front cover on, only the middle injector is avalible to access and it has up or down twist to adjust the mix,

does the other two injectors top and bottom, have to be done up tight or do they need setting as well?
 

Tim Frank

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Re: johnson 1969 55hp carb setting up

You need to get yourself an OEM manual.
 

chris01803

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Re: johnson 1969 55hp carb setting up

lol, ok i will, were is the best place to get one, im from the uk.

any one know now that could help me right away
 

Daviet

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Re: johnson 1969 55hp carb setting up

By injectors, are you talking about the holes in the carb cover? If so , remove the cover assembly and it will expose the carb throats, have someone run the engine at WOT and listen for the popping. If it is coming out of one of the carbs, you most likely have a broken reed valve.
You do need a manual, google Ken Cook or check E-bay. Double check your model number against the manual to make sure the right one.
 

Tim Frank

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Re: johnson 1969 55hp carb setting up

What he is talking about is the linkage for slow speed carb adjustment.
There is one hole through the carb cover over the centre carb....the adjusting lever uses that to connect to the slow speed needle and the connection for carbs 1 and 3 needles run inside the cover.
This makes carb adjustment a PITA and many people drill holes over the Slow speed adjustment on 1 and 3 and pitch the linkage all together.
The holes allow access to all 3 needles and makes carb adjusting far less frustrating.

If that linkage is already missing for sopme reason, he'll have to drill the holes anyway....if he wants to go "OEM", he can PM me and I'll send him the linkage. It's been hanging on my boathouse wall for 30+ years....:)
 

Tim Frank

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Re: johnson 1969 55hp carb setting up

lol, :confused::confused: ok i will, were is the best place to get one, im from the uk.

any one know now that could help me right away

You can "lol", which usually means you have no interest in a manual, but it will save you countless hours, money, frustration, and it will avoid irritating people when you use terms that are simply incorrect....like "injectors" and can confuse the people that are trying to help you out.

Cost you about 40 quid and worth every penny.
 

chris01803

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Re: johnson 1969 55hp carb setting up

thank you all for your help and i am sorry if my words are wrong when trying to explane parts of the engine, as i am a bricklayer i have not much know how of engines,

but tim you are spot on with what you replyed, that is what i was on about, the three long pin things (that better) that go into the carb, and yes the idle speed is set by the middle one,

did you say you had some think hanging on your wall for 30 years that could help me??
 

Tim Frank

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Re: johnson 1969 55hp carb setting up

No, your best bet is to take yours off and hang it on your wall , too....;)

Take the cover plate top a DIY or hardware store and find a plastic or rubber grommet/push cover that matches the hole size where the adjusting lever goes through. Buy three of these.

Then drill out holes where the other two needles sit.

Now you can access all three needles independently and without taking off the cover plate.
It's the only way to really do the adjustment properly.


Since the engine is dependent on fuel flow for lubrication, you don't want a lean carb condition starving a cylinder for gas/oil.
 
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