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Johnson 1977 140hp

J

Jappie

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Hello, I am grateful for finding this forum. I have a Johnson 140 from I think around 1977 (I could not find any plague with engine ID number or other info. I see the bougies that are in it are ngk BHUV they are flat and don’t have a anode or cathode sticking out. What are bougies that I need to use for this engine and are there the right ones? Also, about the coils I noticed three black ones with writing something like “a10 oa” on it and one red coil. Does it matter what coils the engine uses and what are the best for top performance of the 140hp?

When go full gas the boat is only going 40kmh how can we tune this monster to go 60-70kmh which sounds more like that a 140 hp would do? There is this trigger for ignition timing underneath the flywheel that moves when you give throttle how can I tune this? And can the carbs be tuned to improve performance? I think I saw no screw on the carbs that can be turned in or out (only a few on them but with a “o ring” so I assume the carbs can be tuned? Or?

Thank you in advance for the information I hope anyone can help me and we can use top performance of the engine :)

All reply’s are welcome and hope someone can help me get this sorted. :) :)

Greetings Jasper.
 
Ahh thank you so much, a question about wot adjustments https://i.postimg.cc/mkRCstkz/IMG-0816.jpg
On the engine there are some screws and a spark timing lever how can I start adjusting for optimal performance? Can I screw the stop for the max spark timing all the way out? (towards the boat) is it then able to go faster? I drew some colored arrows on the image do you have any idea how I can tune this engine?

Many thanks
 
Post the compression values.----Do not make any adjustments on a wing and a prayer.---And the red lever on the electric primer valve is in the wrong position.---Even looks like it has the wrong carburetors on it.
 
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Alright thank you very much 🙏 what position it needs to be in? I turned it in the past and it didn’t start then. And think you are right, In the box with spare parts I saw a carb silencer part I saw somewhere online as well I can post a picture later today perhaps. Many thanks!
 
Your carburetors show choke flappers.----Not required with the wonderful electric primer valve.--Perhaps it only has 100 HP carburetors on it now.--Good luck in determining the condition of this motor.------And the transom appears to have multiple re-enforcement.-----Not sure I would even take that boat out on a pond !-----Be very careful with your hard earned $$$
 
yes and when I turn the red primer valve flag any other direction she won’t start or go off when she is running , so there was a carb silencer cover plate at the spare parts of this engine so perhaps she did have different carbs in the past, if the carbs are say 115hp (I read those was used on different models) can I order 140hp and screw them in the carbs and then she would run better? I am awaiting delivery of the compression tester gauge. When it’s delivered I’ll post the values here immediately.
I got it practically for free so for now it’s ok to spend a little on it :)
 

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So I checked the compression today: about 130 for each cilinder. The carburetor number on both carbs: 322021. Bougies: 1x champion UL77v and 3x NGK buhw.

In the spare parts was two different carbs with number: 319671.

I now want to order 4x champion UL77v for sake of ruling out bougie issue

For the timing I posted a photo of how many mm it is sticking out, I read online about 10mm this needs to be sticking out? Or am I wrong and confusing something?

Thanks for the help it mucho appreciated! :)
 

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Compression is fine.----On the front of carburetors is the bore size.---Is it 1-3/16" , 1-1/4", 1-5/16?----And post the number found on the high speed jet ( orifice plug ).
 
Alright, 1-5/16 is the size on both the old and the new carbs. Where is the orfrice located? In the top part of the carb or in the float case (lower) part? I checked the old one (top orfrice was saying 30) lower I couldn’t really get out easily. I will check for the orfrice number of the new carbs and post them here probably tomorrow, big thanks!
 
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Jappie said:
Alright, 1-5/16 is the size on both the old and the new carbs. Where is the orfrice located? In the top part of the carb or in the float case (lower) part? I checked the old one (top orfrice was saying 30) lower I couldn’t really get out easily. I will check for the orfrice number of the new carbs and post them here probably tomorrow, big thanks!
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Ok so the lower one is the high speed, in the old that one says 069 if I’m right and I’ll check the new carbs for the number. Any tips on how to get the orfrice out without leaving tiny metal parts everywhere around the objects? Hope then getting them out, it won’t damage engine :)
 
I checked the size of the high speed jets that were on the carbs on the motor and top carb was 67c and the bottom carb was 67c as well. Bore size 1-5/16 for these carbs as well.

Also a other question: what is this hose for? [see attached picture] It is under the recric valves

Thanks ^^
 
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