Fouling Plugs on 1997 Johnson 115 Ocean Runner

[ibm135]

Lately, my 1997 Johnson 115 Ocean Runner has been fouling plugs. After changing plugs with new plugs, the engine runs great. After a few days of hard use (waterskiing, etc.) the engine will suddenly have no power, which is rectified with a new set of plugs. For the first 5 years, I operated with no fouling on the same original set of plugs, but in the last 2 years this has become a repeated problem. I used to run Texaco 2-stroke oil, but can't find it anymore; for the last couple years I used Penzoil.<br /><br />Two questions:<br />1. how do you clean the plugs - carb cleaner does not seem to do a good job.<br /><br />2. How do I correct the fouling issue. <br /><br />Thanks.

 

[Solittle]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

Been there & done that. Run with OMC, Yammy or Merc oil - costs a bit more but will result in a more complete burn where it counts. Replace the plugs.

 

[ibm135]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

That seems a little extreme - $16/gallon for Johnson oil, $6/gallon for Pennzoil (and Texaco which seemed ok until I could no longer find it). Does anybody have an opinion on Quicksilver? Since these are all TCW3 oils, should they not all perform decently? It also doesn't explain why It worked fine on cheap Texaco brand for 5 years with no fouling. However, the common denominator does seem to be Pennzoil brand it did start not long after I switched to it.<br /><br />Is there no way to clean these plugs?

 

[Dhadley]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

What plugs are you using?

 

[seahorse5]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

You should be using the Champion QL78YC plugs gapped at .030".<br /><br />what is the compression, engine temp at idle on each cylinder head, carb mixture settings, and has the sync and link been adjusted by a knowlegable person? Are you pre-mixing the oil or using the oil metering system? What is the top rpm with a full load of fuel and people in the boat?

 

[ibm135]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

I am using the recommended Champion QL78YC plugs gapped at .030. It has a separate oil tank, which I am using, so I am not premixing. The carbs were last looked at last year by a Johnson mechanic, said there was no issue with them. It runs about 5200 RPM at WOT (44mph on the speedo). I changed out the original prop, which I think went to 5500 RPM because it didn't have enough low end to get my fat body up on a waterski in a reasonable amount of time (i.e. before I started gasping for air). As far as compression, I have no idea. I have ordered a manual, (could not find an oem manual, so went with the haynes 80-300hp 96-2002 manual, hasn't arrived yet).

 

[ibm135]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

Don't know what the temp is, I don't have a gauge for temp. When the engine is stopped, and water is draining out, it feels hot to the touch, not scalding hot, but hot.

 

[Dhadley]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

Remember that any TCW rating is a minimum spec the oil has to be made to. IE, there are different levels of quality within the TCW3 ratings.<br /><br />As far as Pennzoil goes, we use Pennzoil Marine Synthetic Blend. Less than 10.00 a gallon and have no issues at all with it.<br /><br />I would suggest an even lower pitch prop when you are skiing. It will certianly improve your "up" time and you wont be lugging the motor.<br /><br />A good decarb job may be in order also.<br /><br />Good luck!

 

[KentuckyBoy67]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

You just said the reason in my book why your fouling plugs: Champion <br />I used to run the Drag strip and bought and bought those reccomended Champion plugs and kept fouling them until another driver told me to buy the best plug you could buy,he said an Autolite or Motorcraft ,well I never fouled another plug after that.<br />It's cross reference time I'd say,it's worth a try.<br /><br />PS.<br />Someone has'nt been messing with the Rich and Lean have they.

 

[G DANE]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

Hi Ibm135<br /><br />I'd suggest you got the ignition tested with a spark tester, to see if you have weak spark on the two. It could bee bad connection or something, as a little weak spark will be fine with brand new plugs. Would explain too why you had no problems with same plugs the former years. Easy and cheap to test

 

[ibm135]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

Nobody has been messing with the Lean/Richness - won't attempt that until I have a manual.

 

[seahorse5]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

Are all 4 plugs equally fouled or is it just one or two from the same cylinders each time?

 

[mav1973]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

i have the same problem i have a 1974 9.9 evin i use champions use the boat for about 8 hours they get fouled going to try other brand of plugs see if that works oil is evinrude oil did use penzoil couple of months ago seem to run little better i hope its the plugs just got the carbs done in june

 

[ibm135]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

They are all about equally fouled, but maybe one cylinder is a little worse (lower left cylinder).

 

[Dhadley]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

Is there water in #4 (the lower port)?

 

[ibm135]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

no water in cylinder.

 

[Walker]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

This isn't the dragstrip, stick with the Champions in your OMC outboard. <br />Did your plug fouling start when you changed props. Something doesn't sound right about the 5200rpm prop pulling you up faster than the 5500rpm prop.

 

[ibm135]

Re: Fouling Plugs on 1997 Johnson 115 Ocean Runner

There was about a 2 year lag between fouling and prop change. I guess I can put the old prop back on and see what the effect is. I believe the owners manual says the prop needs to keep it between 4800 and 5500 rpm.<br /><br />There was more correllation between when I quite using Texaco oil and switched to Pennzoil. I might try a few gallons of Johnson oil after I use up the last of my pennzoil, but my last gallon will probably last till the end of the waterski season.