1983 XJ750K Seafoam Bad?

I have been thinking of using seafoam to clean out my crankcase, because fuel leaked into it after over a decade of sitting. Also wondering if I should put it into the fuel as well, was thinking of just putting it into the crankcase through the oil opening. Not sure how to use seafoam though, I also can't drive it like the instructions recommend, (ie couple hundred miles) since I don't really know how/my bike currently is illegal to ride (not registered, no license plate, No license or training haha). So I'm not sure what to do, really wanting to clean it before winter though. Not sure if idling it would be good enough clean, also heard that having it sit in the bike for too long can damage it.

 

Also was wondering in General what to use as a fuel stabilizer, many people say seafoam is good and also bad, I'm worried it will kill my engine. Wondering if i should just fill it with gas no stabilizer and just hope for the best haha

 

Sea foam will work great. Center stand the bike or find a way to pull the rear right off the ground and make sure it is "Very stable and will not fall". Once the bike's rear tire is off the ground and "very stable" you can start your bike and run it through the gears. This will be almost as good as running it down the road. Remember that you will need to put a fan in front f your bike to help cool the engine as the bike is not moving.

I have used sea foam and other products when I "had" to flush the crankcase out. I have a had a few bikes that were more like mud than oil. You should see the oil window start to clean up and when you remove the oil it should be nasty. Might have to do this more than once to get the effect you are looking for.

As far as damaging the bike, not sure, but you are worried about the clutch friction plates and what will happen to them. That is why you have to use the correct oil in a motorcycle, so the clutch plates stay wet but don't get too soaked with the wrong oil and lose their ability to have friction when needed.

 

Very Interesting! I will try this thanks for the Info! I was planning on rebuilding the clutch anyway because I would imagine it's already toast with all the gunk that built up in there. I plan on using normal 10w40 oil that is Jaso MA rated for winter and then using Shell Rotella T6 Full Synthetic 15W-40 Oil (someone said they use it) once it's spring time and ready to roll. My Manual should get Here on Monday so Ill take a look at what it says for oil, although both my ideas have come from this Forum and from my research it should be okay to use these.

 

I didn't take the time to look at your posts in any other threads, but if you have fuel in the crankcase, there are obviously other issues you've probably been told that you'll have to deal with to prevent recurrence (bad fuel valve/petcock, leaking float needle(s)/seat(s) in the carburetor).

 

Seafoam is ~70% naptha (slow acting solvent) and ~30% isopropanol..... I'd say use it carefully and maybe no more than 25% of your oil. Other similar solvents are mineral spirits/Varsol. However, if any of you are old enough, we used auto trans fluid to clean out engines/hydraulic lifters, etc. as it is high in detergent.... good for wet clutches too. Again maybe 25% of your oil and don't go redlining it, keep things under light load.

As for fuel stabilizer, I use Seafoam, it slowly dissolves gums and residues, the isopropanol takes care of any water. Run a treated tank as the last tank of the year, then flll up and dump in a few ounces of Seafoam. One does drain the carbs before storage, right??