RPM's

mobgod

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Sep 20, 2011
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179
Hi all I've tried to read my manual but a little lost. My RPM's are at 2000 with ears on at idle i was told thats way to high i need to do a sync, what do they mean little lost, they told me to go buy a timing light but not sure what to do next ect....
 

JB

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45,907
Re: RPM's

What outboard, mobgod?
 

Davem3

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May 15, 2011
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542
Re: RPM's

model number will help a lot, please?????

also year and HP too , please???
 

Barnacle_Bill

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Feb 8, 2004
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Re: RPM's

The procedure you need to do is called "link & sync". Your manual will tell you how to do it.
 

emdsapmgr

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Dec 9, 2005
Messages
11,551
Re: RPM's

Keep in mind that the idle on that engine needs to be set when the boat is floating normally in the water and the engine is in forward gear.
Once you bury the exhaust outlet (the prop) 24" underwater, backpressure will cause the rpm's will come down significantly. Any engine will idle high on the trailer. Usually it's more in the 1200-1300 range, so if your engine currently idles at 2000 rpm's you will probably still be too high when you dunk it in the water. A sync and link is a good idea. Also check to make sure the throttle linkage is not binding (causing a high idle) when the control handle is in neutral.
 

mobgod

Petty Officer 2nd Class
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Sep 20, 2011
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179
Re: RPM's

Keep in mind that the idle on that engine needs to be set when the boat is floating normally in the water and the engine is in forward gear.
Once you bury the exhaust outlet (the prop) 24" underwater, backpressure will cause the rpm's will come down significantly. Any engine will idle high on the trailer. Usually it's more in the 1200-1300 range, so if your engine currently idles at 2000 rpm's you will probably still be too high when you dunk it in the water. A sync and link is a good idea. Also check to make sure the throttle linkage is not binding (causing a high idle) when the control handle is in neutral.
Ok thanks but the problem i'm having is with this book can someone try to explain what i need to do for the link and sync? I have the SELOC and the Johnson outboard 1977 service manual i'm just lost on what i need to do
 

emdsapmgr

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Re: RPM's

In a 1977 factory service manual, the sync and link procedure is a mult-step process. The spark syncronization is found in the ignition section, #4, starting on page 4-16. Once you know the timing is set to spec, you need to sync the carbs: The carb syncronization is found in the fuel section, #3. It starts on page 3-17 and describes the throttle cam adjustment. Part of the sync adjustment is the idle timing-set when the boat is in the water-in gear. Make sure your throttle cable is disconnected at the engine when you make any of these adjustments.
 

mobgod

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179
Re: RPM's

In a 1977 factory service manual, the sync and link procedure is a mult-step process. The spark syncronization is found in the ignition section, #4, starting on page 4-16. Once you know the timing is set to spec, you need to sync the carbs: The carb syncronization is found in the fuel section, #3. It starts on page 3-17 and describes the throttle cam adjustment. Part of the sync adjustment is the idle timing-set when the boat is in the water-in gear. Make sure your throttle cable is disconnected at the engine when you make any of these adjustments.
Ok what is the light needed for or is it for one of the above you have told me to look at ?
 

Silvertip

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Sep 22, 2003
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28,771
Re: RPM's

A timing light is used to check the ignition timing. Who told you that you need to do a link&sync and to buy a timing light. Unless the carbs have been worked on those adjustments should not have changed. If you've not done this before and you don't understand what the manual is telling you then I strongly suggest you maintain a "hands-off" philosophy or you will have more problems than just a high idle speed. Do not touch that engine until you figure out what you are about to do.

The long and short of this procedure is that movement of the throttle lever causes two things to happen. It moves the ignition advance and throttle opening on all carburetors in synchronization. Do it wrong and you can do serious engine damage.
 

mobgod

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Sep 20, 2011
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Re: RPM's

A timing light is used to check the ignition timing. Who told you that you need to do a link&sync and to buy a timing light. Unless the carbs have been worked on those adjustments should not have changed. If you've not done this before and you don't understand what the manual is telling you then I strongly suggest you maintain a "hands-off" philosophy or you will have more problems than just a high idle speed. Do not touch that engine until you figure out what you are about to do.

The long and short of this procedure is that movement of the throttle lever causes two things to happen. It moves the ignition advance and throttle opening on all carburetors in synchronization. Do it wrong and you can do serious engine damage.
ok thanks silver but I do need to fix this do you suggest anything for me my idle is at 2000 rpm with ears on I was told I should be around 1100 with the ears so do you suggest I just read the above and go from there ?
 

mobgod

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Re: RPM's

I'm still lost with this my idle is still at 2000 rpm's my idle speed screw can't be adjusted any more i'm at the lowest point this is driving me crazy.... Anything i can look into? Also I did disconnect where the idle speed screw is still have a high idle, but when i push down on the linkage the idle does go down a bit but i can't get it to stay there. Now what I was wondering could this be a fuel problem to much air ect.... carbs need to be worked on ect...
 

dehydrated

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Dec 25, 2009
Messages
299
Re: RPM's

disconnect linkage to timer base under flywheel and push timer base back it should move freely.You could have a sticky timer base old salty grease has a way of screwing up. best to pull it ,clean it put new grease on the brass and two stroke oil on the plastic slide part if its not that you probably have a air leak somewhere
 
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