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Lower/Secondary plugs - oil fouled?


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It was a cold rainy day in Atlanta today so I did the basic mtce I've put off. As background, I have an 04 1150RT with 27K that I bought, sight unseen (Ebay) and it had no mtce history.


But it is in great condition and it looks as if has been well cared for. Nevertheless, I wanted to get a fresh start, so to speak.


So today, I changed the engine oil, filter, xmsn, and rear drive oils, following Jamie's excellent post (compiled during Jury duty-the pictures were a GREAT help - thx) and a less informative after market manual.


I ran the bike up to 5 bars operating temp in the garage, on the center stand, in second gear. Probably not a good idea but I didn't want to ride in this weather. I made sure the back wheel did not touch the garage floor.


All oils looked fairly clean so I assume they were changed recently. Then I put in new plugs. Not a problem until I got to the secondary/lower plugs. My RT has engine guards and I couldn't see a good way to get them off (to get to the low plugs) without removing all the plastic. Not a problem because I want to do a complete, under fairing, cleaning anyway.


1000 screws later the fairings are off and I removed the lower plugs.


They're wet and oily. Oil fouled? Is this normal for the boxer?


The primary plugs looked great - tanned and dry.


Now that the plastic is off, I guess I do the under tank stuff - like fuel filter and air filter. Only problem, I have a FULL tank! (Think I'll just pump the gas into one of the cages.)


This board is a wonderful resource for newbie Beemers.

Like me.

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Can't speak to your plugs but I do have one piece of advice. Don't take the fuel filler cap off unless you feel you must. I did while doing some exploratory work replacing the fuel filter on my 04 RT. The o-ring had shrunk and wouldn't go back on. I ended up buying a new one. Wasn't expensive, just annoying.

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Haven't seen that on my twin spark '04 boxer. Is it possible you got oil on the plug while removing it? If the inner round valve cover seal is leaking, then oil runs down into the lower plug cavity. Just wondering if there was oil in the cavity when you pulled the plug. If so, replace those lil' round seals. If not oily, can you test to be sure the plugs are firing by holding the connected plug against some metal to see if there is a spark when the engine is turned over? Be careful.

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I have seen this twice on the lower plugs on an '04 and heard about it a more than a few times as well. Generally, after about 12,000 miles or so it should stop. Since you don't have any service records, it could well be that those are the original plugs and it would not be totally unexpected to find them oily. At this point in your mileage, your bike should be about finished burning oil. I would expect a toasty tan, normal looking set of lower plugs on your next change.

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It's possible for the plugs to be a bit fouled if all you did was run it on the centerstand with no load, and perhaps the lower plug has a tendency towards this. Leslie's comment makes me think that perhaps it does.


I'd check again after a decent run where the engine was under a normal load for a while, I suspect that the plug will look better.

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I also bought my 04 RT used, 11k miles at the time. When I changed the plugs at 14K miles (had to ride it from Atlanta to central CA) the lower plugs looked slightly fouled. Since then they've been fine at every change; currently 44k miles on the odometer.

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daveinatlanta, as mentioned above it is very possible that you didn't run the engine under enough load to burn the fouling off those lower plugs.. If that is the case they will clean right up a good hard run..

It's also possible those plugs aren't sparking properly.. Make sure you do have a good bluish colored spark on those plugs while cranking the engine (ign switch & kill switch on)..

I had an old Yamaha with 2 spark plugs per cylinder but only one plug hooked up & that ALWAYS had the non sparking plug fouled when inspecting.. (just make sure you do have a good spark on those lower plugs)..



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I think the 'fouled plugs' are a result of --


1. They're the originals. It looks like minimal under fairing mtce has been done and I suspect the previous owner changed oils - and that's about it. The reason for this conclusion: the fuel filter appears to be the original - and all the clamps are crimp type. Lots of dust under the tank - nothing greasy - just dusty. Most of the hardware under the fairing is dusty with an occasional greasy spot where you'd expect one. (Tomorrow - WD40, and Simple Green)

2. I did run the bike without a load. The cyls didn't get hot enough.


I checked the spark today on the lowers and it is good on both sides.

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I FINALLY finished the job - 6:30PM. Changed xmsn, final drive and engine oils, spark plugs the air cleaner and the fuel filter - the original one which lasted 27k miles. Did a top to bottom wax too.


In doing this over the last three days, I learned a lot about the RT.


I also learned that the next time the fuel filter needs replacing - to take it to the dealer!



But I feel good about the time investment, knowing that basic maintenance issues have been addressed. I didn't know the bike's history. Now I know some of it.


The postings, instructions and walk-thoughs here were invalable.

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