Synthetics for Inboards and I/Os

[mkuehnl]

With the boating season coming to a close and the winterization process is in full swing. What's the word on synthetics for I/Os and Inboards? Am I just throwing my money away if I change my oil and put in the more expensive synthetics? They don't break down as quickly and I am running a Merc 350 (Chevrolet) tournament ski at a consistant 3000 to 3500 RPMS.

 

[L Christopher]

Re: Synthetics for Inboards and I/Os

mkuehnl, My manual says DO NOT USE SYNTHETIC OIL in my 5.7 liter Merc. Check your manual or call the service department at a local dealer.

 

[adrew]

Re: Synthetics for Inboards and I/Os

Trailer Boats magazine covered this topic in their May 2001 issue. I don't remember the particulars but it seemed to suggest that it would be okay to use synthetics but for most boaters, a non synthetic would work just fine. See if you can find this issue, it may help you decide.

 

[dhammann]

Re: Synthetics for Inboards and I/Os

Save your money and use what the Mfg. recommends. I have been in the business a long time....there is no snake oil for engines, just profits for those who pry on people's fear. Condensation is your worst enemy, so stick with any API oil and change at recommended intervals. Stay away from multigrade oils, these have viscosity improvers that will stick rings...the wider the range e.g. 10-50w the worse it is.

 

[snapperbait]

Re: Synthetics for Inboards and I/Os

Even though the manufacturers of synthetics say they have improved the problem with oil seals not swelling and sealing properly, I still would stick with conventional motor oil... Rear main seals are a pain in the U know what to replace...