TCW3 vs. XD-100 E-Tec oil in older outboards

[Smokin' Joe]

Here's a pretty good article

http://www.sea-doo.net/techarticles/oil/oil.htm

It explains that synthetic oils like XD-100 need higher temperatures to get rid of the ash on the exhaust stroke. Here's my question: anyone have experience running (and mixing, no oil injection) XD-100 in 1993 and earlier OMC motors, especially smaller ones at higher RPM?

I have friends who run XD-100 in the ca. 1993 V-6 (mixing oil and gas) at 9000 RPM. I've run it in my 1983 Johnson 35 @ 6100 RPM. With the cooler than standard Champion L2-G (I've got a bunch of them from 1985, but they're still made excepting the electrode isn't gold plated) the plugs ran slightly wet and the motor spit and missed in a strange way when I backed off the throttle fast (mixture is 37.5/1). With standard heat range L3-G/L77J4 the plugs run chocolate brown and dry. I don't idle much, so the question is whether to expect deposit buildup running wide open. With dry plugs I'd think not (I haven't pulled the head, the motor was rebuild recently). I worry about sticking pistons because I advance the spark to 33-34 degrees, but then run enough 110 Sunoco leaded along with pump 93 octane to get 95 octane fuel.

I'm wondering what to expect if I run XD-100 in our 1981 Evinrude 15 @ 6500 RPM (37.5/1 mix). The motor's in Germany, pump 95 octane is available.

[Powerabout]

nice article
I like the part where it says there is no API definintion for synthetic oil
and tcw oils are only tested to 6800rpm

the BRP etec skidoo engine does 8500 so they spec api-tc amongest other reasons

[Smokin' Joe]

nice article
I like the part where it says there is no API definition for synthetic oil
and tcw oils are only tested to 6800rpm

the BRP etec skidoo engine does 8500 so they spec api-tc amongest other reasons

There's a nice article about oil in the April, 2009, AOMCI 'The Antique Outboarder'. There, Amsoil is strongly recommended for both antique and classic motors. I have a young friend who drag races, he and machinist built own block starting from ca. 1995 OMC V-6 looper, reengineered the computer too), is forced by the drag association to run Klotz oil. 9000 RPM.

[Mark75H]

I would be suspicious of any article suggesting any particular brand of oil over others. Leans too much toward propaganda and advertising. We all know that there are a lot of very good oils and few people have problems regardless of the brand they use unless they ... just plain forget to put oil in the tank.

I couldn't find the part that said synthetics needed higher temperature ... it said synthetics withstood higher temperatures

There is a part that talks about additives and the temperature to disperse deposits, but I did not see where it related to a specific oil type ... it related to the specific additives ... and I was under the impression these additives were generally in mineral oil based lubricant, not synthetic


Also note that the article comes from a fan site like BRF and is not on a manufacturer's site

[Powerabout]

Mark 75
What BRP was saying is that very few oil producers bother to pay to (many say they meet or exceed it but dont) get api-tc approval.

Its an old spec and probably should be updated.

[Smokin' Joe]

Here's a quote about too much deposit at low RPM from oil designed for higher temp.:

"Therefore, the use of these high performance oils in outboard or other mildly tuned 2-stroke engines is not recommended. Some manufacturers are using a combination of detergent types (Ashless and Low Ash) to provide a broader range of uses for their oil. It is important to note that oil designed to meet TCW3 specs. only (Ashless) will not protect an engine requiring API-TC (Low Ash) type oil. The converse is also true. Using a Low Ash oil in an engine designed for an Ashless type oil only could result in fouled plugs and gummy combustion chambers."

I haven't found a more recent article.