'82 V6 calls for 88 Octane?

[dajohnson53]

The powerhead is a J235 1982. Remanufactured in mid-90s - this is a apparently a total, proessional factory type reman because the engine is labeled with the company that did it (no longer in business, can't call). I bought it used about 3 years ago. When I bought it, the guy said "always burn premium", so I have been. Of course, I've been reading all along that one should burn 87 octane or whatever the manufacturer calls for.So, I get an OEM owner's manual (booklet - not the service manual). Fuel specified is 88 Octane, "not unleaded", "not gasohol".Obviously, the wording in this old manual is dated, but I'm wondering about the octane spec. The pumps around here have, I think (from memory), 87, 89 and 90.Can I ASSUME that the remanufacturing process modified the engine so that it can burn 87 safely? Should I just be safe and burn 89? Is there some timing or other spec that would need to be checked to determine if I can burn 87?Is this nothing more than an angels dancing on the head of a pin question?Thanks guys for indulging my obsession.

[Mod2]

Moving to Outboard Non-Repair Discussion forum.

[Solittle]

D. Time to get an education. Go to the red search at the top of the page & enter octane for a search arguement & read away.

[dajohnson53]

Sorry, I must be dense. I've read a lot of posts about octane in the various forums, but still don't know the answer to my question. Thanks anyway.

[PuddleJumper]

Some say 89 (mid-grade) fuel has better additives for your motor,but 87 is ok for almost all 2 strokes except High compression/high performance engines.I would suggest try 87. As long as it doesn't ping or knock you are good to go.

[walleyehed]

That engine runs quite well on fresh, Name-brand 87 Octane...89 is usually the mid-grade and contains the 10% alcohol, which we really need to avoid, if possible.It takes a trained ear to "hear" the ping and Identify it when it's in the initial stages.If it scares ya to run 87, back the max advance off by turning the screw in 2 turns....(2 degs)but I'm sure fresh 87 is just fine.

[Mercathode]

Be on the safe side and run the higher octane rating. Use a good brand of oil.

[dajohnson53]

Thanks for the answers, guys. There is no alcohol in the gas where I live. I ran a tank (25 gal) of 87 through it and didn't notice any change in performance. I didn't hear any pinging, but from the sounds of it I probably wouldn't be able to.

[walleyehed]

I understand your concern, but you must understand what high-test fuel does to the internals when it isn't required...Your engine does not require high octane and you are loosing performance and engine longevity by running it...it's simply not needed.

[dajohnson53]

Thanks walleyehead - since I started reading these forums, I've learned about what premium is designed for, when it is required as opposed to what regular's designed for and when it is best. I now know that premium is not always better and can actually be worse in performance than regular. But that 88 octane spec in the old (pre-rebuild) manual just had me thinking... so I appreciate your comments. I'm going to burn regular from now on.Just for curiousity sake though, and not that I'm expecting it, is it possible for a layman to recognize pinging in a loud old V6 outboard? If so, other than hearing it and having it pointed out to me, how would you describe it.

[walleyehed]

It is literally a "ping" on every combustion stroke that has somewhat of a "ring" to it...Have you ever pulled a hill towing your boat and heard your vehicle do it??

[dajohnson53]

Yes, I've heard my cars do that (not recently - but certainly in the past). If it's that simple, I feel very comfortable in being able to hear it. Thanks for the info and advice.