Johnson 175 idles a little rough

[Anthony Rembisz]

Anyone know why my outboard doesn't idle smooth?  87 Johnson VRO .175 hp. 

Here is a video of it running. 

 

 

 

 

It's actually kinda hard to hear it but it like jumps every few seconds. And when it does that the engine like shakes. Also I am noticing water coming out if some seams in the lower unit. Is that bad? You can kinda see what I'm talking about in the video.

 

 

I'm new here and any knowledge would be much appreciated!

[A-Jay]

Hello Anthony and Welcome to Bass Resource ~

 

Is this a trick question ?

 

If you are inexperienced or even a little unfamiliar with the inner working of that 32 year old motor,

perhaps take it to someone who is not.

 

A-Jay

[jbsoonerfan]

Please, please, please take it to a mechanic and let them look at it. There are very knowledgeable people here, but I don't know if they can help you.

[Way2slow]

Well, I happen to know just a little bit about them.  Enough to know that first off, you can't tell a whole lot about the way one idles when connected to a hose.  It requires the back pressure created when the motor is sitting in the water at it's normal depth.  Second, even then, the motor needs to be trimmed so it's level (vertical to the waters surface.  Tilted like you have now throw the float level way off. 

Now, if it's in the water, at the proper depth and idling rough and lean spitting, you probably need to do a full linc and sinc on the throttle control linkage and carbs and verify timing.  In all probability you will end of having to clean the carbs also.

[Breakwater Bouy]

Well, if it were me (I have been in your shoes with an outboard chasing gremlins around many times) I would start with a compression test, then do a compression leak down test and see what you have with the internals of the engine--  your findings will lead you in the direction you need to go to trouble shoot your issue. If the internals are healthy I would go to the ignition system and test everything per specs-- use a true shop manual that will go into great detail on every section of the outboard, however they are a bit vague about getting out v4 thermostat housing and install ect other than pulling the power head....I'm no professional mechanic and don't claim to be either. I have built many hot rods over the years and that knowledge help me when I work on my outboards

[Elkins45]

I would run it submerged and under load before I decided to start messing with it. Lots of rough idling problems go away once a little bit of fresh fuel goes thru the carbs.

[Way2slow]

Looks like another of those one post wonders.

[East Iowa River King]

Put some seafoam in it.  Replace the spark plugs.  Everything about motor height is true when running, makes a difference in carbureted engines.  Looks like that lower unit has see alot, however its hard to tell whats really leaking in it if its hooked up to the muffs. 

[Breakwater Bouy]

any update? on the troubleshooting of this issue