Link n sink?

N

niner

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I have had some problems with idle on a 1989 60HP, I have the max spark advance set no problem runs great off idle. Heres my problem setting my idle advance, I can set it on the hose (idles good) but when I get it in the water I have to turn the idle screw about 2 turns to get it to idle and hence the timing is off. when I set the line up on the roller for the throttle pick up and try to set the timing it wont idle. PS carbs are clean, comp is within 5psi in each cylinder. engine seems to only want to run at a very fast idle (ie more timing) a little faster than I like on the hose. no RPM gage.
 
JB

JB

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Re: Link n sink?

Idle must be set with exhaust back pressure on the engine, niner. That means in the water or in a tank.

Good luck. :)
 
N

niner

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Re: Link n sink?

I understand, but I can't get idle without increasing the timing, while in the water. could my timing marks be off 2-4 degrees.
 
rickdb1boat

rickdb1boat

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Re: Link n sink?

Have you done a complete link and sync per the manual? Do your carbs have the low speed mixture needles?
 
N

niner

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Re: Link n sink?

rickdb1boat said:
Have you done a complete link and sync per the manual? Do your carbs have the low speed mixture needles?
Click to expand...

Trying too, just can't set the timing at idle.
Yes it has low speed adjustable jets. They are set per manual.

I can almost count the RPMs while on the hose and timing set to 2 degrees BTC (base) just wont idle in the water without adding more advance.
 
SuperNova

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Re: Link n sink?

I had a Johnson of almost the same vintage that had the exact same symptoms. I tore my hair out for an entire season with constantly trying to adjust it. It turned out the reeds were worn out. Don't know if it's the same with yours or not, but it's worth telling you about.--
Stan
 
peacekeeper6

peacekeeper6

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Re: Link n sink?

i just went through this and have deceided that it needs to idle higher outside the water then inside, so i just leave it at about 1000-1200 outside the water when flushing and she idles fine inside the water nw and runs great, (I HAVE A 200HP THOUGH) dont know if its the same thing.
 
N

niner

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Re: Link n sink?

SuperNova said:
I had a Johnson of almost the same vintage that had the exact same symptoms. I tore my hair out for an entire season with constantly trying to adjust it. It turned out the reeds were worn out. Don't know if it's the same with yours or not, but it's worth telling you about.--
Stan
Click to expand...

I have thought about the reeds since Idle is the only problem and the vacuum is the greatest at idle it could be not letting the reeds seat if they are weak, How do you check them?
 
72SideWinderSS

72SideWinderSS

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Re: Link n sink?

What you are referring to as "Idle Timing" is really "Throttle Pickup Timing"
As long as the marks line up at the referenced setting i.e 4* then your "Throttle Pickup Timing" is correct.
The carb's are designed to idle with the butterflies closed and the Idle Speed is then adjusted with advancing or retarding the timing with the "Idle Speed Adjusting Screw". The "Idle Speed Adjusting Screw" might not even move the butterflies.
Hope this Helps.
 
SuperNova

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Re: Link n sink?

niner said:
I have thought about the reeds since Idle is the only problem and the vacuum is the greatest at idle it could be not letting the reeds seat if they are weak, How do you check them?
Click to expand...

I honestly don't know how you check them. I had just been through everything else and decided they were the only thing left that could be doing what I was experiencing, so I tried just flipping them over but that didn't help and finally I just replaced them. Magically, the engine ran great.
 
N

niner

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Re: Link n sink?

72SideWinderSS said:
What you are referring to as "Idle Timing" is really "Throttle Pickup Timing"
As long as the marks line up at the referenced setting i.e 4* then your "Throttle Pickup Timing" is correct.
The carb's are designed to idle with the butterflies closed and the Idle Speed is then adjusted with advancing or retarding the timing with the "Idle Speed Adjusting Screw". The "Idle Speed Adjusting Screw" might not even move the butterflies.
Hope this Helps.
Click to expand...

This helps me understand the procedure a little better, So it's OK to have a little more timing at idle, Just as long as you set the timing and throttle pickup to spec. So I assume it's OK to set the timing on a hose and set the idle in the water.
 
72SideWinderSS

72SideWinderSS

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Re: Link n sink?

niner,

"So it's OK to have a little more timing at idle, Just as long as you set the timing and throttle pickup to spec."

That is correct. As long as the butterflies just begin to open at the pickup timing spec your carbs and timing are then in sync.

"So I assume it's OK to set the timing on a hose and set the idle in the water."

Correct again, I do mine that way.

FWIW
On my setup I can set my idle, on the hose, @ 1100 RPM and when I put it in the water the idle will be just right.
 
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