Rough Idle and Missing

BadBoy

Cadet
Joined
Jun 1, 2001
Messages
28
Hello I have a problem with my bothers 1996-1997 130HP Johnson.<br />It is Idling rough and is missing here is a list of what i have done so far.<br /><br />I have checked the Coils and they are producing a real strong spark and all are firing great.<br />Cleaned out the carbs found some Water in the fuel bowl's.<br />I cleaned everything Checked the VRO oil tank and found water in it.<br />cleaned and flushed it ran motor again and it still Idles rough and is missing and a puff of white smoke comes out every 30sec or so.<br />This thing is driving me crazy I have been working on it for 2 days and cant find the problem and get it running right.<br /><br />And the fuel pump and VRO unit was replace 3-4 month's ago.<br />And I checked the compression and that is good all were the same.<br />I did notice that when i took the spark plugs out they seemed alittle wet with fuel and oil.<br /><br />Please someone help me with this problem I dont know what to do next I think it may be the timing but do know how to check it.<br /><br />Thanks<br />BadBoy
 

papasmurf

Petty Officer 2nd Class
Joined
Nov 9, 2004
Messages
181
Re: Rough Idle and Missing

Is it just missing at idle or thru the rpm range?
 

duke3

Petty Officer 2nd Class
Joined
Jun 30, 2005
Messages
108
Re: Rough Idle and Missing

How old is your sparks ?<br />What is your spark-gab ?<br />And what kind of plugs are you using ?
 

fireman57

Captain
Joined
Aug 24, 2004
Messages
3,811
Re: Rough Idle and Missing

If you have white smoke I would suspect water in the cylinder(s) possibly from a bad head gasket or you are still picking up water from the fuel somewhere. You may want to put a seperator inline somewhere.
 

BadBoy

Cadet
Joined
Jun 1, 2001
Messages
28
Re: Rough Idle and Missing

Yes it is missing true the RPM range<br /><br />Spark plugs are new the gap is .35 or .40 i think<br />And the brand is Champion.<br /><br />How can i find out if i am getting water in the cylinder's.I did a compression test and they were fine.I am sure it is not getting water from the fuel and oil any more i even tryed hooking up a differnt gas tank with pre mix oil to see if the VRO was mixing right (took the oil line off frist so it would not over mix)<br />And yes we do have a fuel inline seperator.<br /><br /><br />Thanks<br />BadBoy
 

MCM

Lieutenant Junior Grade
Joined
Jun 1, 2005
Messages
1,201
Re: Rough Idle and Missing

Hi, Any idea how the water got in the system, it seems there would have to be a leak somewhere, this leak could also be resulting in a vacuum leak, a vacuum leak can result in poor performance and backfiring.<br /><br />Mike :rolleyes:
 

BadBoy

Cadet
Joined
Jun 1, 2001
Messages
28
Re: Rough Idle and Missing

Originally posted by MCM:<br /> Hi, Any idea how the water got in the system, it seems there would have to be a leak somewhere, this leak could also be resulting in a vacuum leak, a vacuum leak can result in poor performance and backfiring.<br /><br />Mike :rolleyes:
Well Gas got into the VRO oil Tank becouse someone did not put the cap back on the tank.<br />But we flushed everything and are not getting water in to the carbs anymore check the bowls about 5 time's.<br />So i know its not etting water there I dont know if it is geting water into the cylinders but did compression test the m and the were fine.<br /><br />This thing is driving me crazy<br /><br />Thanks<br />BadBoy
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: Rough Idle and Missing

Could the puff of white smoke have a blueish tint to it? - - I'm thinking it might be unburned fuel rather than water.<br /><br />When you cleaned the carbs did you completely dissassemble, soak overnight, blow out with high pressure compressed air and install new carb kits? If not - - - -
 

fireman57

Captain
Joined
Aug 24, 2004
Messages
3,811
Re: Rough Idle and Missing

Have you checked for spark yet? Sounds like you could be arcing to the block from a plug wire. If you run it with the cover off can you hear a popping sound? Is it possible to run it at night in a barrel and look for sparks flying? A compression test won't show a bad head gasket all the time. Only way I know of is to pull the head and visually inspect the cylinders for wear and moisture. Do not reuse the same gasket no matter how good it looks.
 
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