AAHHH!!!! 86' johnson 120 won't stop sneezing!

evil grady

Seaman Apprentice
Joined
Jul 25, 2004
Messages
49
I changed the 4 oneway recirc valves and the vacuum lines. I rebuilt all 4 carbs. It idles way better than it did but still sneezes and stalls at idle. <br />The motor runs on premix(no vro). It has new plugs,coil pack,waterpump and battery. <br />It will idle with muffs but not in tank.<br />please help!! I'm going crazy!!! aaahhh!
 

DHPMARINE

Captain
Joined
Dec 16, 2003
Messages
3,688
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

Does your engine have carbs mounted on a throttle body?If so the throttle body contains the idle passages that can cause your problem. (lean spit)<br /><br />DHP
 

Walker

Captain
Joined
Jun 15, 2002
Messages
3,085
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

Also there should be a recirculation line going to the top main bearing carrier. There is no one way valve up there but the nipple must be free flowing both ways.
 

evil grady

Seaman Apprentice
Joined
Jul 25, 2004
Messages
49
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

I'm not sure about the idle passages?I'll check them in the morning. What clogs the line to top main Bearing carrier?<br />What if they check out? Any other things I should check?<br />Walker, do you work at a marina? you always seem to have good advice :)
 

alcan

Commander
Joined
Dec 14, 2001
Messages
2,505
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

Hi evil<br />Just to add to the already great advice. The number one culprit with SNEEZING is an air leak somewhere in the fuel system. Alot of times it is the fuel line connection or connector that is bad. This is very common with after market connectors. This is a commmon problem to all outboards and all connectors. The sneezing is due to a lean condition caused by sucking in un-metered air (more air than needed). This may also be caused by leaking gaskets, hoses,etc. The fuel tank not being vented properly or vent plugged, anti siphon valve, might be a problem?
 

Walker

Captain
Joined
Jun 15, 2002
Messages
3,085
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

There are a bunch of guys here that know a lot more than me. I used to work at a small private shop. Now I just piddle at my house. Been working on OMC's for about 12 years. I brought the clogged nipple deal up because I own a 94 120 and chased that problem for several months before I figured it out. I don't know what was clogging mine up and I couldn't clear it. Ended up busting the bearing out of the carrier and buying another used carrier from a different motor just for the bearing. The bearing is a proprietary item for OMC and is not available except as a complete carrier/bearing unit.
 

seahorse5

Rear Admiral
Joined
Jan 24, 2002
Messages
4,698
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

A few more things to check out:<br /><br />Make sure each cylinder head is running at least 125 degrees and ideally, 140 degrees. You may have bad or missing thermostats and/or grommets that are making the motor run "cold".<br /><br />Check the 4 throttle plates to make sure they are completely closed at idle and that the timing is around -6 to -8 degrees( 6-8 ATDC)<br /><br />Make sure the carburetor side covers are not leaking air into the idle passages. Use a cleaner type spray with a small nozzle to fit into the brass air jets on the front of the carbs. Spray into each jet and see if there is any leakage around the side cover gasket. The metal plates warp easily. You can use a large diameter #10 washer on the middle screw to help seal the "lambrynth" underneath. Use new gaskets, used ones will not always reseal.
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

With the carburetor face plate off, and with the engine running at an idle, one carb at a time, insert two fingers into the carburetor throat which will act as a choking device. Should any of the carbs be running lean for any reason, and the engine suddenly smooths out when you insert your fingers as above..... that particular carburetor has a problem.
 

P.V.

Chief Petty Officer
Joined
Mar 14, 2002
Messages
452
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

Everything stated above!! AND.... do a sync and linc, TO THE LETTER!!!! per the factory manual!!
 

evil grady

Seaman Apprentice
Joined
Jul 25, 2004
Messages
49
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

Wow! Great info everyone.. I'll get to work but first I need to get heater going in garage, its like 20ish outside!<br />I will report back..<br />Dave
 

evil grady

Seaman Apprentice
Joined
Jul 25, 2004
Messages
49
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

Ok, I stripped the carbs off. The reeds are clean and the gasket is fine(now I will get 2 new ones. <br />one of the little vac lines was caught in the airbox cover. It has a minor cut in it but never the less a vacuum leak. <br />Also one of the thermostats, when opened, puked water ,the other didn't. The one that had water in it was rusty?<br />Last but not the least. The motor has been converted to a non vro motor. <br />Heres the catch, It looks like a small pump model #328781 Is this a real number?<br />Its not the vro delete pump. What should I do?<br />please help!!
 

Solittle

Fleet Admiral
Joined
Apr 28, 2002
Messages
7,518
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

grady - You wrote "What should I do?<br />please help!! ".<br /><br />They have helped - - You got a bunch of good advice above from some knowledgeable guys - - - follow it.
 

evil grady

Seaman Apprentice
Joined
Jul 25, 2004
Messages
49
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

Solittle, I know I got great advice and I am very grateful! <br /> My what should I do was a question on the fuel pump. Is it the right one, will it work, should I buy the right one? <br /> Also do you think there is anything wrong with my thermostats?
 

walleyehed

Admiral
Joined
Jun 29, 2003
Messages
6,767
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

I'd change the T-stats out while you are there, no question.<br />That fuel pump is just a standard fuel pump, I believe....shouldn't be an issue there. did you replace the diaphram in the fuel pump???<br />One piece of Fly crap can cause idle problems as well as the items mentioned already. Keep the parts CLEAN and free of any contamination when rebuilding.....a small piece of anything can ruin it for ya.
 

seahorse5

Rear Admiral
Joined
Jan 24, 2002
Messages
4,698
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

The 120 and 140 hp series use the "VRO" as a fuel pump. The diaphragm can be replaced, but if it is an old style original pump, a new up to date one would be a better choice.<br /><br />Refer to the Engine FAQ section F.
 

walleyehed

Admiral
Joined
Jun 29, 2003
Messages
6,767
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

Maybe I misunderstood, but I believe he meant the VRO was "gone" and had just a std fuel pump on it...????
 

evil grady

Seaman Apprentice
Joined
Jul 25, 2004
Messages
49
Re: AAHHH!!!! 86' johnson 120 won't stop sneezing!

Yes the VRO set up is gone and I pre mix. <br />Someone replaced the pump with a pump that looks rather small. It has a part number on the back of<br />328781. <br />I was wondering if I should change it to the correct non vro pump or should I spend alot and put in a whole new vro system!
 
Top