Rough Running Johnson 30 HP

[Haffiman]

Re: Rough Running Johnson 30 HP

Haffiman, just for future reference.
Where is 250V from the power pack specified in the CDI troubleshooting guide?
Thanks. Jasper

If not mistaken it is in the OEM manuals. It is the same voltage you have in the stop circuit which in fact 'drains' the capacitor to ground when activating stop.

 

[Timberwolf17044]

Re: Rough Running Johnson 30 HP

Well I kinda wish this is what I had at the beginning of this process. Would have made it simpler. In all my searches for info somehow I never thought to use the terms " CDI Troubleshooting Guide". Sometimes asking the right question is the hardest part..

View attachment DVA Chart - OMC.pdfView attachment OMC 2 Cylinder 1977-2006 4-60 HP.pdf

 

[jasper60103]

Re: Rough Running Johnson 30 HP

If not mistaken it is in the OEM manuals. It is the same voltage you have in the stop circuit which in fact 'drains' the capacitor to ground when activating stop.

Yes, I see it. Thanks.

Timberwolf,
just another piece of info for the record...

 

[Timberwolf17044]

Re: Rough Running Johnson 30 HP

Well I am happy to report that the power pack arrived ( quite quickly also). Installed it this evening and after an oversight in installation ( failed to connect the ground from the power pack properly) the motor once again runs, Wooooo Hooo!!! happy happy day. Sad to say however there now seems to be an additional problem. It stalls out when I try to give it any throttle. I've attached a video and will tear into this problem most likely tomorrow after work, my initial thoughts are a vacumm issue, perhaps in my fooling around under the cowling with the plugs and coils and power-pack I may have dislodged something. Regardless I am making great progress and perhaps if the weather cooperates I may still get a chance to test it out on the river before winter really sets in.

http://www.youtube.com/watch?v=tt9YfCKDjns

 

[AlTn]

Re: Rough Running Johnson 30 HP

is the float set level with the carb body when the carb is inverted?...nozzle gasket in place?...did you switch to the champion plugs?...mix is 50:1?..fuel pump isn't leaking back through the pulse hole?..can you screw the idle mix screw all the way in and the motor quits?...even taking into account that it's running indoors, that exhaust looks very rich

 

[Timberwolf17044]

Re: Rough Running Johnson 30 HP

Just a quick update, I looked at the motor briefly before leaving for work this morning and found part of my problem. The limiting screw on the right rear of the motor ( a nylon screw) Which I assume has something to do with timing on full throttle got broken somewhere in this process. Would anyone be able to tell me the bolt size/thread and length of this bolt? I'm sure I can find something locally to replace it with. I was thinking of a stainless steel bolt with a rubber cap slipped over the end so as not to cause any wear on the plate.

 

[AlTn]

Re: Rough Running Johnson 30 HP

looking at diagrams for your model no. another suspect appears....do you have the electric or manual primer and ,if either, are they possibly leaking fuel into the intake?

 

[Timberwolf17044]

Re: Rough Running Johnson 30 HP

looking at diagrams for your model no. another suspect appears....do you have the electric or manual primer and ,if either, are they possibly leaking fuel into the intake?

It is an electric primer. After reading your post I got to thinking about the way it was running rich and checked the position of the primer manual override... I had it forward.. the manual override switch so as long as there was power to the switch there was fuel being dumped directly into the intake and of course it would also create a very rich running situation. You would think they could tag or mark that darn thing anyone could tell at a glance lol

 

[Timberwolf17044]

Re: Rough Running Johnson 30 HP

Well folks I gotta say this motor is doing its best to drive me nuts. After getting home this evening and double checking sure enough, all the time I've been testing and running this motor the primer had been in the manual position, definitely causing a very rich running position. So now, with the primer in the proper position, a bolt installed where that nylon one had broken off, rechecking positions of the butterfly in accordance with previous instruction and adjusting it via that stop on the metal rod at WOT... I can't keep the motor running. Acts now like it is starving for fuel. I can keep it running somewhat by holding in the primer at the switch, or by lightly spraying some carb cleaner directly into the carb. Which I guess is leading me back to the carb for a third time. Knowing the carb is definitely clean the only suspect I have is a possibility that the float is not set properly. I do know the first time I had it apart I placed the float in upside down.. or suspected I had. However I am not 100% certain on its position with the carb inverted. Unless someone can provide me with other suggestions that's where I'm going next.. for the third time. There is a reason why people do this work for a living lol

 

[jasper60103]

Re: Rough Running Johnson 30 HP

Sure sounds like a fuel restriction. Next time, try squeezing the fuel bulb. This should over ride the fuel pump and force gas to the carb bowl. Of course, if the float valve is stuck close, this won't help.

In any case, never use carb cleaner to keep her running. That's bad for your motor. Instead, put some fuel mix in a squirt bottle.

Also, I included a couple pics of my carb adjustments. And don't forget the blow test.
Hang in there, you'll figure it out.

 

[Timberwolf17044]

Re: Rough Running Johnson 30 HP

Thaks Jasper I sure appreciate yours and everyone's help on here. I did try squeezing the bulb to no avail which makes me look to the carb. That float test is the one thing I did not do so thats next

 

[Haffiman]

Re: Rough Running Johnson 30 HP

The most critical part in that carb is the round gasket in center. Hold the carb up-side, install inner and outer gasket and it must be a gap between bowl and outer gasket when bowl is just put on top. If inner gasket is to thin or cracked it will leak air and not suck fuel.

 

[Timberwolf17044]

Re: Rough Running Johnson 30 HP

Well here is another update,
Pulled carb off again last night and rechecked everything as before. I am now certain float is adjusted properly. I cannot see any wear in any parts with the lone exception being the gasket between the bowl and the carb body. I guess it is the only gasket except for the one between the carb and the intake. So anyhow, it isn't broken or cracked that I can see but it is slightly deformed. The inner gasket that Haffiman speaks of I assume is that very small one the encircles the jet shaft going up into the carb and it looks to be fine. With all that said I reassembled everything and also verified the fuel line and all the vacuum hoses, no cracks no pinches, in fact I'd wager a guess there are very low operating hours on this motor the darn thing just looks so new inside. Tried running it after all was said and done but still have the same issue. Hard to get to idle and when I do get it to idle there is no throttle, dies out the moment I try to give it any. Also to there is no response from adjustment of the rich/lean adjustment. I'm sort of thinking that that carb gasket is allowing it to suck air so my next approach will be a carb rebuild kit just to eliminate any possibility with the carb. Any other suggestions? As an added thought when I was running it last night I had to keep pressing the primer button to get it to run and then after it was good and warm it would idle somewhat. Without full knowledge on the history of this motor, keeping in mind it has sit idle for several years, 3-4 at least, it smacks of something drying out or failing from some sort of degradation, metal components wouldn't do that but fiber components like gaskets, hose etc would. I'm hanging in there lol....

 

[Haffiman]

Re: Rough Running Johnson 30 HP

Please double check your sparks again. I really unlucky, you may have killed the new powerpack when running (trying to run) without the ground wire. Use a spark tester or timing light to verify correct spark at both cylinders.

 

[Timberwolf17044]

Re: Rough Running Johnson 30 HP

Please double check your sparks again. I really unlucky, you may have killed the new powerpack when running (trying to run) without the ground wire. Use a spark tester or timing light to verify correct spark at both cylinders.

I have spark, it wouldn't run at all without that. When it comes to the use of a timing light I've not used one in years so perhaps you could refresh my memory on its use?

As an after thought perhaps I should clarify a bit. I am aware of the proper usage of a timing light. I am also aware that I should connect it to the #1 plug. In this case I am assuming that would be the top cylinder. I am also aware of where the timing marks are on the flywheel but I am not aware of where the stationary indicator is that I would use to reflect what the timing actually is.

Additionally, I have heard the phrase lync-n-sync. Is the procedure discussed earlier in this thread regarding the relationship between the cam follower, butterfly and throttle linkage this same procedure?

 

[AlTn]

Re: Rough Running Johnson 30 HP

yes, that's the linknsync...I've found it helpful to use clear tubing from the fuel pump to the carb bowl to rule out fuel delivery problems, you should see a solid column with no air bubbles when it's running...timing light verifies spark going to plugs on both cylinders, so just clamp it on one at a time, the ignition timing itself isn't adjustable on that motor...swap those autolites out

 

[Timberwolf17044]

Re: Rough Running Johnson 30 HP

More news..
Refer to the link below for a picture of what I am talking about. Working on it again this evening I am now convinced it is a fuel delivery problem. The main reason is that if I hold my hand over the opening of the carb I can keep the motor running. My question refers to the bowl section of the carb. At the center where that small round gasket sits atop a small lets call it a stand pipe, that is where the tubes drop down into the bowl. Does anyone know just how far they drop down into the bowl or rather hos far off the bottom of the bowl they actually sit and if there is a screen in the bottom of that section? Referring to an earlier reply about that small gasket being thin or cracked it appears to be in great shape, however the outer gasket, not cracked or tore that I can see it is compressed quite a bit, I would say nearly half its original thickness. With that said is the tolerances of the pick up tube so close that it could be too close to the bottom of the bowl and not allowing enough fuel up the tube into the carb?

http://www.marineengine.com/parts/johnson-evinrude-parts.php?year=1987&hp=30&model=J30ELCUB&manufacturer=Johnson&section=Carburetor

 

[Haffiman]

Re: Rough Running Johnson 30 HP

Completely remove Jet #19 and check that it is clean!! If 'frozen' use carb cleaner and a very thin thread and be sure it is open. Pour fuel down the center and it should come out in the bowl.

 

[Timberwolf17044]

Re: Rough Running Johnson 30 HP

Completely remove Jet #19 and check that it is clean!! If 'frozen' use carb cleaner and a very thin thread and be sure it is open. Pour fuel down the center and it should come out in the bowl.

This is listed as an orifice plug???? Is this a jet that feeds the tube going up into the carb body?

 

[kfa4303]

Re: Rough Running Johnson 30 HP

Hi timberwolf. It looks like part #19 is a fixed (older models were adjustable until around the mid '60s) high speed orifice. It's used to regulate fuel delivery at high speeds and start up. Based on your description of covering the carb throat to get it to start, you're essentially "choking" the motor, which essentially lowers the amount of air in the combustion mixture, thereby increasing the relative amount of fuel(i.e."richens" the mix" This suggests that the motor is not getting quite enough fuel at start up. The most likely culprit is indeed a slightly clogged Hi speed orifice. I would try Haffiman suggestion. It can be hard to get to the jet, but a small, flathead screwdriver should reach it. You may have to file down the sides a bit, but it can be done. If you can't/don't want to remove it, try using aerosol carb cleaner, compressed air and/or a guitar string or wire to help thoroughly clean out the passage. As you can see, it's very small and can be clogged up pretty easily. It only takes a small amount of debris to trow off the fuel:air mixture, and with the ethanol in modern gas, it's easier than ever for varnishes and deposits to build up. Give these tricks a try and let us know what you find.