How do I remove 56 Johnson Javelin carb??

[jimmbo]

Do you still have the original engine? If so you have an engine to compare any changes.

 

[KathyD19]

Do you still have the original engine? If so you have an engine to compare any changes.

No the original engine with the boat was a Mercury "Tower of Power"

 

[oldboat1]

Do you have a parts manual? https://www.ebay.com/itm/1956-JOHNS...at=0&_nkw=1956+Johnson+manual&_from=R40&rt=nc

Not pristine(!) but an oem manual. (not my listing)

 

[KathyD19]

Update...life got busy and I got hadn't done any more on the motor. I did a barrel test and it sounded ok so I took it to the lake today. It runs smoother without the surging or "lean sneezing" that it did before. Starts right up (with no choke, have never needed to use the choke) but sounds so slow, like it's barely running. I put it in gear and putted out of the marina no wake zone then kicked up the throttle. Blah. At full throttle it only runs as if it's about 1/4 to maybe 1/3 throttle. The butterfly isn't opening in the carb throat fully at full throttle, only open a small bit. I don't know how I've managed to get that out of wack. I've tried adjusting the thumb adjustment on the remote throttle cable both ways to see if it causes any effect on the the throttle and I'm not noticing any difference per se. I don't have anyone who can go with me on the boat to run it while I adjust the low and high speed needles so I was adjusting them a little at a time myself then would hop back and forth from front to back. I can't detect a bit of difference in how the engine runs by adjusting the low speed (top needle) at all. The only thing I notice is the fumes are richer when I turn it out to the 1 1/4 point and there's more oiliness on the water so it's obviously running richer but performance-wise, no difference in sound or action. I've had two summers with no lake fun with the motor and I feel like I'm thisclose to solving this dilemma so I'm frustrated. I KNOW that motor can work good, I've had it at top speed a few years ago and it was awesome. I don't know how things got so out of wack now with the throttle and needles. My brother said to just sell it and find another motor. I've put so much into this and you all keep telling me what a great motor it is, I hate to give up. Thoughts?

 

[jimmbo]

Remember that little 'Fuel Saver' adjustment( Referred to in Poat # 57, 58, and maybe a few more)? That is what pushes the carb fully open after max timing is acheived

 

[KathyD19]

I just got off the phone with my brother (grew up working on 2 stroke engines, but not a lot of boat motor experience). He said I have to deal with the timing issue, get that adjusted properly or everything else is screwed up. I was never able to figure out how to adjust that cam plate to be sure the scribe line and pointer lined up just as the butterfly valve was opening so I just tightened the screws back up. I think that has a lot to do with it. So I'm going to readdress that issue. I will also look at that fuel saver collar again to be sure it's set to allow the carb to fully open, jimmbo. Thank you! One more thing, my brother asked if the motor has reed valves or is a piston port? I didn't know so I'm asking you all. He said reed valves can go bad and need replaced.

 

[flyingscott]

Your motor has reed valves. If they were bad you would have fuel being blown out the front of the carb. I would say that in not your problem.

 

[jimmbo]

Reeds. Reeds don't break very often, when they do, the engine runs very poorly, like a dead cylinder type run, spits gas back out carb. They can also do a lot of internal damage, being a very hard metal.
Regarding the sync issue. Here is a later 3rd party service manual excerpt


Edit: Scott beat me to it while I was typing

 

[jimmbo]

Timing is determined by the opening of the breaker points. On your engine, a very close setting is obtained by removing the access cover on the flywheel and adjusting to 0.020".

 

[lindy46]

DON'T mess with anything else until you get the link and synch correct.

 

[KathyD19]

Ok, so good to know that it's got reeds and also that you guys don't think that's the issue. Back to the drawing board regarding the link and sync. I do have a printed copy of that service manual jimmbo but your page is much clearer, thanks. I just can't figure out why the cam plate is not adjustable. The holes for the two screws are perfectly round, not slotted so there is not any room for movement. If it were the later model with a fixed cam on the magneto armature plate then there would be an eccentric bushing yet I don't see that. Thanks for the the ideas so far...keep 'em coming!

 

[jimmbo]

The Reeds are called Leafs in the parts and the service manual

Looking at one of you pics of the screws holding the cam to the armature plate. It looks like a fairly big washer above the lockwasher. Did you have the bolt out and saw there was no slot?

 

[KathyD19]

Jimmbo no I did not actually remove the entire bolt because I figured it would be a nightmare trying to get that back in there again, I'd only loosened it. I used a dental mirror to get a view of the hole and saw it was round. If you're correct and that's a large washer, that would explain the hole I saw (and it's shape) Is a washer supposed to be on there or has someone added it at some point, I wonder? Yet even with a washer, if the bolt is loosened, if it sits in a slotted hole, it should still be able to move, right? Unless that washer was stuck and holding it in a place. I might have to use my gorilla-hand dental hygienist strength to see!

 

[jimmbo]

I was thinking more along the lines of some gentle prying on the cam outwards using a screwdriver.
Spray some penetrating oil along the join line, perhaps it is just stuck from dirt/old oil

 

[KathyD19]

Got it, no Gorilla-hands! Just some good old PB Blaster and I actually got a small amount of movement on the plate now!! Important question: in the instructions it says I have to "hold the THROTTLE VALVE closed while making the adjustment." Is the throttle valve what I have been calling the "butterfly valve" in the throat of the carburetor? How do you hold that closed? When I have the scribe and pointer lined up, it's still closed anyhow.

I've unhooked the remote throttle cable and am turning by hand to line up the scribe line and pointer. The instructions say "to remove all the slack from the linkage". Does that mean slide the cam plate forward (towards the front of the boat) as far as it will go against the cam roller, then tighten the screws to hold it there? I think I need 4 hands for this! Once this is accomplished, does the butterfly just start to open as the scribe line goes past the pointer?

Sorry for all my questions and thanks for putting up with me! I've loosened the fuel saver collar and slid it out of the way until I get past the link and sync procedure. I'm hoping I'm attacking these issues in the correct order.

 

[jimmbo]

"Got it, no Gorilla-hands! Just some good old PB Blaster and I actually got a small amount of movement on the plate now!! Important question: in the instructions it says I have to "hold the THROTTLE VALVE closed while making the adjustment." Is the throttle valve what I have been calling the "butterfly valve" in the throat of the carburetor? How do you hold that closed? When I have the scribe and pointer lined up, it's still closed anyhow."

They just don't want the throttle plate opening during the adjustment.

"I've unhooked the remote throttle cable and am turning by hand to line up the scribe line and pointer. The instructions say "to remove all the slack from the linkage". Does that mean slide the cam plate forward (towards the front of the boat) as far as it will go against the cam roller, then tighten the screws to hold it there?"

Yes, that's the general idea, but until it just touches the roller

"I think I need 4 hands for this! Once this is accomplished, does the butterfly just start to open as the scribe line goes past the pointer?"

Yes, well it's supposed to

"Sorry for all my questions and thanks for putting up with me! I've loosened the fuel saver collar and slid it out of the way until I get past the link and sync procedure. I'm hoping I'm attacking these issues in the correct order."


Sounds like you are

 

[lindy46]

When the pointer lines up with the scribe mark on the cam, pull out on the cam until you just start to see movement in the rod connecting to the carb butterfly. Then tighten the cam bolts.

 

[KathyD19]

It was darned near impossible to hold everything in place while trying to reach that adjustment screw to tighten it but I think/hope I got it. I'm attaching a couple videos I just took...sorry for my lousy videography skills but hopefully you can see what I've done and am doing. The first video just shows you how the cam roller and cam plate are moving and the effect it has on the throttle valve WITHOUT the fuel saver collar on. Then I put it on and made another video showing how things move with it in place. With the collar on, the throttle valve will open fully. I did have it on when I lake tested the other day but like I said, I was never able to get the motor to throttle up much faster than about 1/4 to 1/3 speed. I have a lot of questions in the second video about what things are and what they do but my main question is how to know exactly where to place that collar on the fuel saver rod. I'm sure I have notes on that somewhere in my lengthy journey with this.... Sorry I sound so down in the video, been a long day and I was under attack by a huge cicada while trying to do the link and sync (cicada is completely flat now btw) https://youtu.be/G_VMZhoniLg
https://youtu.be/plXwPW9hqd4

 

[jimmbo]

Hi Kathy
Watching the second video, I will say you have the collar set to contact too soon. All the timing advance is supposed to be completed at the point of contact with the collar. The last paragraph on the page I sent you(post 88) explains the procedure. Here is here is a repost with the continuation of the last paragraph and another pic from the book

 

[KathyD19]

Alrighty Jimmbo, thanks for the reminder with the manual info. I also found one that said " set speed control grip to fast position with shift in forward. To assure maximum spark advance make certain armature plate bracket come to rest firmly against the crankcase boss by exerting thumb pressure. Slide collar up on link until it rest firmly against pivot pin Secure in this position by drawing up lightly on the lock screw." So if I understand what you're saying correctly, that the collar (as I have it now) is set to make contact too soon, after properly setting it, it should be further LEFT on the rod? I'll do this method then take a pic of where it ends up.

Another question: I've very limited by what all I can test in the barrel in my driveway because of course it has to be run in neutral and that limits how far I can take the throttle. I know NOT to put it in forward or drive in a barrel but is there any way (or is it even a smart idea) to bypass the throttle governor that limits it to half way at neutral, only temporarily so I can see if it's working properly? Hauling the boat way out to the lake to test it is a pain, especially since it never works right and I really need it back at home to do any work on it since that's where all my tools are. There are only a couple docks to launch from and I can't tie one up working on my Problem Child. Thanks again for all of the advice. I'm sure this is frustrating for you; like teaching algebra to a 3 year old!