I cant get this throttle set up properly. Please advise.

timmyjane

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Pontoon rebuild.
New 24’ cables.
Can’t seem to get throttle set properly based on everything I’ve read.
Adjustment says link and sync. Butterflies closed at neutral. Done.
Burtterflies horizontal at WOT. This is where I have an issue. Nothing I do seems to get them horizontal. Not even close really.
Also the engine seems to remain at high RPM at idle.
Timer Base has been removed and cleaned. New lithium grease applied. I have ensured that no wires are catching it.
It doesn’t seem as if there is enough travel in the cam to open the carburetors all the way up. I am all ears to any advice. I can’t seem to get it figured out.
Thanks. IMG_2568.jpeg
 

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jimmbo

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First of all what Engine?
Second, what are you using for a Service Manual?
Third, what have you fiddled with so far?
Forth, When you say you can't get the Throttle Valves Horizontal, was that with or without the New Throttle Cable connected?
 

timmyjane

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First of all what Engine?
Second, what are you using for a Service Manual?
Third, what have you fiddled with so far?
Forth, When you say you can't get the Throttle Valves Horizontal, was that with or without the New Throttle Cable connected?
Sorry. Just realized I didn’t give that info.
78 Johnson 85hp.
I have an old Johnson manual and the internet. Generally this forum.
I’ve fiddled with pretty much everything in the entire assembly. (I realize the timing will need to be addressed again.)
The valves will go horizontal when manually actuated but with the cables attached there is not enough movement to pull the arm, to push the roller to a fully open/horizontal position.
 

timmyjane

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In order for the valve to go to a fully horizontal position the roller has to be way past the bottom mark on the cam.
 

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jimmbo

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Sorry. Just realized I didn’t give that info.
78 Johnson 85hp.
I have an old Johnson manual and the internet. Generally this forum.
I’ve fiddled with pretty much everything in the entire assembly. (I realize the timing will need to be addressed again.)
The valves will go horizontal when manually actuated but with the cables attached there is not enough movement to pull the arm, to push the roller to a fully open/horizontal position.
So the Cable Length needs adjusting. In one of the Pictures you can see the Threaded brass of the Cable, there is an adjustable Trunnion there to adjust the Cable Length. It is generally used to put a bit of Preload on the Throttle Linkage to keep the linkage against the Idle Stop. In this case It appears to be set at Minimum Length, way too short.
 

timmyjane

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So the Cable Length needs adjusting. In one of the Pictures you can see the Threaded brass of the Cable, there is an adjustable Trunnion there to adjust the Cable Length. It is generally used to put a bit of Preload on the Throttle Linkage to keep the linkage against the Idle Stop. In this case It appears to be set at Minimum Length, way too short.
Thanks Jimmbo. I felt like it was way too short also. I even mentioned to my neighbor that it seems odd that it would require that much adjustment to align with the mounting stud. This is how much I had to screw it in to go on. Should I be applying pressure to the arm to get it and the mounting stud into the proper position and then adjust the cable to that length? Seems so. I was allowing the arm to find its own, neutral, spot.
 

jimmbo

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Put the control lever in neutral, that should have the Cable at Idle, place the Throttle Linkage against the Idle Stop, adjust the Cable Length, until it is the length needed to fit on the Linkage, then a bit more to push the Linkage against the Idle Stop slightly.

Might have been a bit easier, if you had used the cld Cables as a Guide as to where to place the Adjuster on the new Cables

You also have to check the New Shift Cable too

Max timing doesn't change on these engines, unless someone has "adjusted" it. You will have to check it, then go thru the Link and Sync again. Is your Service Manual Specific to your engine, Year and Model?

Idle Speed is adjusted with the Throttle Cable unhooked, because a change to the Idle Speed will change the Length the Cable needs to be. Once the Speed in gear, is correct, reattach the Cable, and add a little bit of Preload, to keep the linkage against the Idle Stop.
 
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timmyjane

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Ok. So I just went out and made all the adjustments. I have made those adjustments before. (This is my second new set of cables as the first ones were too short and made a bind.). The details came back to me as I made adjustments.
The idle stop is screwed all the way in. This moves the mounting stud furthest away from the cable end to provide the most amount of length adjustment available.
With the cable placed on the stud at this position the cable adjustment is screwed almost all the way in as shown above.
The carbs do not open all the way up with the cable adjusted like this.
By adjusting the cable further out the butterflies will go horizontal. The arm will not go back to the idle stop. This is also seen that the roller will not go back to align with the mark on the cam. It’s not even close.
To get the motor back to idle position and the cam and roller in alignment it seems the cable must be adjusted all the way in.
There is clearly something that isn’t right.
The last set of cables gave the same trouble so I’m sure it’s not a cable issue.
Getting this thing adjusted to where it has full travel shouldn’t be this difficult or tricky. I’m very mechanically inclined. Built houses, boats, cars and airplanes. These cables and carbs are really throwing me off. I appreciate the help.
 

jimmbo

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Ok. So I just went out and made all the adjustments. I have made those adjustments before. (This is my second new set of cables as the first ones were too short and made a bind.). The details came back to me as I made adjustments.
The idle stop is screwed all the way in. This moves the mounting stud furthest away from the cable end to provide the most amount of length adjustment available.
With the cable placed on the stud at this position the cable adjustment is screwed almost all the way in as shown above.
The carbs do not open all the way up with the cable adjusted like this.
By adjusting the cable further out the butterflies will go horizontal. The arm will not go back to the idle stop. This is also seen that the roller will not go back to align with the mark on the cam. It’s not even close.
To get the motor back to idle position and the cam and roller in alignment it seems the cable must be adjusted all the way in.
There is clearly something that isn’t right.
The last set of cables gave the same trouble so I’m sure it’s not a cable issue.
Getting this thing adjusted to where it has full travel shouldn’t be this difficult or tricky. I’m very mechanically inclined. Built houses, boats, cars and airplanes. These cables and carbs are really throwing me off. I appreciate the help.
At this time Forget about the Cable. Get the Engine set up and running correctly. Once that is all fixed, and the Idle Speed is Correct, Adjust the Cable Length as needed. Now inside the Control Box, is there more than One Mounting Spot for the Cable End?
Also, is there a chance you have the Shift and Throttle Cables mixed up? When the Throttle/Shift Lever is moved, the Shift Cable moves First, then once it stops the Throttle Cable starts moving. I don't think the Shift Cable moves as much as the Throttle Cable
 

timmyjane

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At this time Forget about the Cable. Get the Engine set up and running correctly. Once that is all fixed, and the Idle Speed is Correct, Adjust the Cable Length as needed. Now inside the Control Box, is there more than One Mounting Spot for the Cable End?
Also, is there a chance you have the Shift and Throttle Cables mixed up? When the Throttle/Shift Lever is moved, the Shift Cable moves First, then once it stops the Throttle Cable starts moving. I don't think the Shift Cable moves as much as the Throttle Cable
Ok. Moving on.
The motor runs good from a combustion and spark perspective. Just before I started this throttle cable swap I took it for the first run. It ran hot and wouldn’t idle down on its own. The thermostats were replaced. They were jammed up and cruddy. I initially attributed the idling issue to the cables adjustment and later them being too short. When running, on the water, you could reach over and push the cable arm attachment bracket (?) back and it would idle down. The idle did get better as the boat warmed up.

At home, I pulled the timer base and clean it up. Re-greased it, and put it back.
Checked and set timing at 24°, (Book calls for 28°) following the JR WOT timing method/guide.

I’ve fired it up a few times while checking the, assumed, cable issue. I did have the idle set to about 1000 RPM on the rabbit ears.Still was a problem returning to idle after giving it a little juice. Determined cables were too short. Ordered 24’ ers. No chance of being too short this time.

New cables installed yesterday morning. I was really hoping that would fix the problem and all would just fall into place. It didn’t.

I then focused some on the control box which has also been a big deal in this build. Original box that went to the original motor (current motor is #2) was damaged. This box is a replacement . Current = Box 2 motor 2.

The throttle lockout piece was damaged so I designed and 3d printed one. STL found here. Anyway, so I opened it up to make sure the piece hadn’t failed. It was ok. There are no other cable mounting spots. I’ve also ensured that the box cables ends correspond to their proper spots in the outboard.

So really, that brought me back to the cables and the throttle assemblies on the block.
I messed with it for a couple of hours this morning. And another go around this evening. Struggling to figure it out.
 
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jimmbo

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So which control box are you using? Photo

If the Books says 28 degrees use 28. The timing is already retarded from what they used in the early 70s. You will have to redo the Link and Sync after.
Are the Carbs fully closed at Idle?
If it has trouble returning to Idle after giving it 'Juice', that is usually because there is no Preload on the Idle Stop.
 
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timmyjane

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I just saw your edited post 2 or 3 above.
Couldnt use the old old cables to measure. The original control box was a hidden style. The one I am using now is a side mount.
I was not adjusting the idle with the throttle disconnected. I also figured it might be a bit high become I’m on rabbit ears at home. I’ll try setting and adjusting like that in the AM.

I’ve messed with all the screws and adjustments up there. Made sure time was put back properly though. While doing all that I did go ahead and clean up and paint the flywheel. That looks nice. Wife told me I was wasting my time. She’s tired of seeing this old boat in the driveway but she’ll be happy when it’s going. Making us a fishing barge.
 

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jimmbo

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Which piece did you replace? #67?
Are use using #40 as the Throttle Lever? It is only for warm up, and doesn't have full range
1693101129130.png
 

timmyjane

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Yes, Part 67.

Ok on the 28°. That 28 is from the old Johnson manual and not a new one. Your advice still apply?

No, I’m using the proper lever. I understand it that the warm up lever doesn’t really even move the carbs that much if at all. The timer base more than anything, if I understand that right.

Yes, carbs are closed at idle. I can either have fully closed at idle or the ability to have them horizontal at WOT, but not both.

I need to better under the preload requirement.
 

jimmbo

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Yes, Part 67.

Ok on the 28°. That 28 is from the old Johnson manual and not a new one. Your advice still apply?

No, I’m using the proper lever. I understand it that the warm up lever doesn’t really even move the carbs that much if at all. The timer base more than anything, if I understand that right.

I need to better under the preload requirement.
If I had your motor, I would have no hesitation setting the Timing at 28, I would also make sure I wasn't over propping it. If you're worried set it at 26, as 24 will drop your HP quite a bit

For the first 75% of the Throttle Lever Movement, the Carbs remain Closed, they really only start really opening after Max Timing has happened.

Preload is simply a bit of Pressure/Tension by the Cable to keep the Linkage against the Idle Stop when the Control is at its slowest Setting or in Neutral.
 

timmyjane

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I am assuming you picked up that I was setting the time using the Joe Reeves method that calls for 4° less than book value. To be clear, I don’t know squat about outboards so I’m not questioning you just ensuring you have the proper info. You say 28 I’ll go 28.

I’m going to get a barrel to operate this in. Maybe that will help too.

I forget what pitch it is. I took it to a pro shop to clean up. They felt like it was a good fit.

I didn’t realize till the other day that I have a long shaft. Really needed a short. Luckily people seem to just give these old OMCs away. Hoping I can get a different lower sometime.

Thanks for the advice so far. I’ll report back after tomorrow’s good times.
 

brodmann

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It's been a long time since I've been inside one of those old OEM boxes, but I believe somewhere in there is a stop that only allows the throttle to go so far. Am I remembering correctly?
 

timmyjane

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No type of stop that I can see. The shift lever has a full range of movement.

Is there a setting for this part? A way to ensure that it is where it’s supposed to be?
 

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