I have my cylinder off of the engine, and was wondering about something that someone told me. They said that you could drain the oil, and leave the drain plug out. Then spray WD40 all over the crank, and gears, and anything else inside that you can see, and let the WD40 wash away any grime and run out the bottom drain plug. Does this sound like a good idea, while I have the engine apart? Does anybody think that it would hurt anything? It sounds like it might be a good idea, just let it drain out then once the engine is put back together, fill it up with oil, and follow new engine brake in procedures, and change the oil after about 20 minutes of running the engine. What do you guy's think? I sure don't want to hurt my engine by doing this, but if it wont hurt it, it sounds like a good idea.

Please let me know what you mechanics think.
Thanks!

 

what kind of engine are we talking about here?

 

It is off my 1985 Honda ATC 350x. I am having a big bore kit put on it, and was wondering if this would be a good idea to clean the inside of the case out while I had the cylinder apart.

Thanks

 

guess it couldn't hurt

 

This is a two stroke, but a similar concept. Before the cool head on my FL350, I went through a couple pistons. It did not hurt the bottom end, but it had a lot of aluminum dust in it. I put the cylinder nuts on the studs and put two big rubber bands from corner to corner through the connecting rod, filled the bottom end with mixed gas and whipped the motor over. I repeated until I could not see any more aluminum dust and then a couple times more for good measure. It has been apart once this year for inspection and everything was within spec. I plan on taking it apart soon for another inspection. I doubt I will find any problems.

 

I always use good old kerosene to flush my engines then finish the cleaning with brake parts cleaner.Make sure you use the flammable kind of b.p.c.It seems to do a better job.Daryl

 

The cancer causing brake cleaner does a better job than the stuff that has not yet been proven to be cancer causing [img]i/expressions/face-icon-small-happy.gif[/img]. Either way, just don't breathe it.

 

I am assuming you probably have piston debris in the bottom end? Take the side cover off (clutch pack side) and stop by your local car wash and spray the bottom end of the engine out completely from the top of the case. Make sure and spray it out very good and take your time. I have done this before and its the 2nd best way to clean the bottom end (best way is to split the cases and do the job right). Next, I use a couple of cans of brake cleaner for the really stubborn attached debris......flush it out with water again....and let it dry. After starting the engine and letting it run for 10 minutes or so, replace the oil.

 

Thanks for all the response's guy's. I don't think that I have any aluminum or anything in the crank case, it actually looks really clean inside. I just thought that since I have the cylinder off, and I am doing a complete top end rebuild that I might as well clean/rinse out the bottom end just to know that there is no sludge or anything in there. There isn't anything that I can see. I guess if you can spray water, gas, and brake cleaner in there, then it won't hurt to flush it out with WD40.

Thanks again.

 

You may still have to take the side cover off for any potential debris to find an easy out. I would change the oil quick after initial startup.......it will be almost impossible to get the sticky WD-40 outta there. Later.