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Honda 30 RPM Dropping at Idle??

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What would cause my Honda 30 to drop in rpm when warmed up in neutral at idle from ~950 to ~625 rpm (where it becomes really rough) I give it some throttle (1200 rpm) then stabilizes back to ~950 rpm then slowly drops back down (2-3 minutes). Haven’t let it drop till the engine dies. Running at speed and when in gear at idle aren’t any problem. Only when in neutral at idle. Happens both on water and on muffs, seems more exaggerated with muffs. Autostart enrichment valve?? Any ideas would be greatly appreciated. Thanks.
 
Adjust pilot screws 1 7/8 turns out.(hope it is adjustable,some models it cant adjust ), fuel enrichment valve you can check by resistance 15 -18 ohms ,operation you can check by supply 12 V to terminals ( Brown wire + ) after 5 min of supply enrichment circuit should fully close,the needle should come out fully.

One more things is all three carb throttle valve should synchronize, for that you have to perform vacuum test,



wajira
 
Well, what comes to mind as I turn this one over in my head is that, if it were a sync or enrichment problem, it should exhibit the same symptoms in gear as it does in neutral. So, I think it may be a linkage or shift cable issue of some sort.

The idle advance lever in the remote console is "bypassed", so to speak, when the outboard is shifted into forward or reverse. So, that is something that I would be looking at.

But first, in order to prove it is or is not a remote or cable issue, you should disconnect the cables for the throttle and shift linkage and then operate the throttle and shift the trans by hand to see if the problem persists or not.

If it does and the base carb idle screw is set properly, with tension spring intact, then it is most likely a sync problem.

If the problem is alleviated then I would be trying to figure out what is happening with the idle lever on (in) the remote console.

Good luck.
 
wajira said:
Adjust pilot screws 1 7/8 turns out.(hope it is adjustable,some models it cant adjust ), fuel enrichment valve you can check by resistance 15 -18 ohms ,operation you can check by supply 12 V to terminals ( Brown wire + ) after 5 min of supply enrichment circuit should fully close,the needle should come out fully.

One more things is all three carb throttle valve should synchronize, for that you have to perform vacuum test,



wajira
Click to expand...

jgmo said:
Well, what comes to mind as I turn this one over in my head is that, if it were a sync or enrichment problem, it should exhibit the same symptoms in gear as it does in neutral. So, I think it may be a linkage or shift cable issue of some sort.

The idle advance lever in the remote console is "bypassed", so to speak, when the outboard is shifted into forward or reverse. So, that is something that I would be looking at.

But first, in order to prove it is or is not a remote or cable issue, you should disconnect the cables for the throttle and shift linkage and then operate the throttle and shift the trans by hand to see if the problem persists or not.

If it does and the base carb idle screw is set properly, with tension spring intact, then it is most likely a sync problem.

If the problem is alleviated then I would be trying to figure out what is happening with the idle lever on (in) the remote console.

Good luck.
Click to expand...

Thanks guys. I'll try jgmo's linkage/shift cable theory first, then go from there.
 
Will the wrong pole setting on the tach do weird things to idle? Not only at the tach read out but on the engine side?? Just wondering cause settings were put to the correct position and all seems okay.
 
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