'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.<br /><br />So, I get an OEM owner's manual (booklet - not the service manual). Fuel specified is 88 Octane, "not unleaded", "not gasohol".<br /><br />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.<br /><br />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?<br /><br />Is this nothing more than an angels dancing on the head of a pin question?<br /><br />Thanks guys for indulging my obsession.

 

[Mod2]

Re: '82 V6 calls for 88 Octane?

Moving to Outboard Non-Repair Discussion forum.

 

[Solittle]

Re: '82 V6 calls for 88 Octane?

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]

Re: '82 V6 calls for 88 Octane?

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]

Re: '82 V6 calls for 88 Octane?

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]

Re: '82 V6 calls for 88 Octane?

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

 

[Mercathode]

Re: '82 V6 calls for 88 Octane?

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

 

[dajohnson53]

Re: '82 V6 calls for 88 Octane?

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]

Re: '82 V6 calls for 88 Octane?

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

 

[dajohnson53]

Re: '82 V6 calls for 88 Octane?

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.<br /><br />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]

Re: '82 V6 calls for 88 Octane?

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

 

[dajohnson53]

Re: '82 V6 calls for 88 Octane?

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.