Hi all
I have heard that running synthetic oil through the engine 3 or 4 times will disolve and clean out all the gunk from years of use…any thoughts on this??? thanks and hope everyone is enjoying summer…Mike Schiff TAYVA 407 N30U Pultneyville NY
Using synthetic oil will also clean out your wallet!
don’t rub it in Mike..LOL
not as much as a new engine
LOL love it Mike!.. I use Marvel Mystery Oil added to existing oil. I swear it runs smoother now. Also add it to my fuel. Worked in the old days for some of my clunker cars!
Hi Mike (Schiff),
You already have the most immaculately clean boat in the fleet…now you want the cleanest engine too! 
Nice to hear from you. Sorry you weren’t able to make the TINA rendezvous this summer.
Cheers,
Joel
Joel Watt
N 30U #258, Virgin Gorda,
Kingston, On
Mike:
I am far, far from an expert, but I have not heard that claim.
I do recall years (decades) ago, when detergent oils were being marketed, there was a caution about using them on older engines which had been run a long time on “regular” oil. The caution was that using detergent oils on engines having a lot of accumulated deposits could loosen those deposits too quickly and clog oil passages in the engine. If true, that fear might also apply to introducing synthetic oils into an older engine.
The comment about cleaning out your wallet is quite true. My 2009 VW Jetta TDi is a diesel and VW specifies that only their specified (and branded) oil be used, or the engine warranty is violated. They charge $12-13 per quart! The upside to that cost is VW says it lasts 15,000 miles. I haven’t done the math, but that might balance it out.
An afterthought: I don’t know what “synthetic” means. I can’t imagine it being made from anything other than good old crude oil, perhaps with more additives (maybe like good old Marvel Mystery Oil or STP) and higher refining. The Wikipedia definition just confuses me.
http://en.wikipedia.org/wiki/Engine_oil.
Joe Tierney Allegro 1992 NS33 #64 Annapolis, MD
Hey Joel
Good to hear from you and hope next year we will join up with you and the group …you know what they say about being clean…Hi to Sondra…Mike and Jeri
A Westerbeke expert once told me that I could double the time between oil changes if I changed to synthetic oil. NOTE: Don’t do this (double the time) on a new boat or engine since it might void the warrantee.
Allen Ames
A friend of mine who is a BMW old car enthusiast tells me that fully synthetic oil in an older engine can make the oil seals leak.
Allan and Judy N26c Swale Ottawa Canada.