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To Flush or not to flush?

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Posts: 362
Joined: Tue Jan 25, 2005 3:04 pm
Location: North-East Ohio

To Flush or not to flush?


Post by Ohio-Rider » Tue Mar 29, 2005 4:50 pm

I recently aquired a 56 FLH from a friends widow after his untimely death and am getting ready to change the oil for the first time. He kept all his rides clean and well mantained and I sure don't want to damage the engine. I'm unsure if he was using synthetic or real oil in it but I plan on using real oil 50W. Would it be ok to just drain the tank and put the real oil in or should the system be flushed out? I guess what I'm asking is can you switch back and forth from synthetic to real oil or vice/versa with out any fear of damage? I went over and rumaged thru my old friends garage to see if I could find a clue as to which oil he was using only to find both real oil and synthetic oil on his self's. I guess he's laughing at me now. So what do you guys think? Flush or Not???

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Location: Central Illinois


Post by Cotten » Wed Mar 30, 2005 2:30 am

There is nearly always some sediment.

I do not bother with the lines, but after draining, I toss a quart or so of mineral spirits, or kerosene back in an plunge it with a turkeybaster extended with ~4" of tubing.
Sometimes I even hit it with air if I'm outside where I can make a mess.

A drain and flush and maybe a repeat removes most of what may come loose in service. It is a prudent 15 minute operation.

I have no experience with synthetics.



Post by VT » Sat Apr 02, 2005 6:36 pm

8) and with a major rear chassis disassembly; cap the outlets, count out 1/4" nuts...put 20 of them in with the solvent and slide 'em around for about an increment hour... wouldn't do too much shaking and dent the tank..keep doing it and changing the kero until it comes out clear. in the final stages, I'm catching the dirt through a paper paint strainer to see the color of metal that comes out last. More bronze than rust nuggets. Count the nuts again.

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