82 black max 150 timing procedure

[Mybiggles]

Can't seem to find much info on checking timing on these motors. I've timed my 82 115hp i6 before and assume it's a fairly similar process

Specs I found online say
max timing should be 25 degrees BTDC
Idle timing should be 8 degrees ATDC
is this correct? Which cylinder is #1 when looking at the plugs?

​​​​​​Where is the fuel mixture screw on the carbs and is the base setting (2 turns out from fully seated) and procedure the same as the i6 carbs?

I've deleted the idle stabilizer if it makes any difference

 

[Dukedog]

https://www.hydrostream.org/ArticleArchives/Timing.htm

there are no adjustments to carbs..

 

[Chris1956]

Timing procedure is the same as for the inline Merc. Double check the max spark advance setting. I like it to be more like 21* BTDC. Idle pickup timing is usually 0-8* ATDC.

 

[Mybiggles]

Thanks guys. What cylinder is #1 when looking at the plugs? Is it the top right?

That link says 25 degrees, you say 21 degrees and I'm pretty sure my airbox sticker says 18 degrees max lol Just want to confirm this as I don't want to cause more harm then good... Is 87 octane ok to run on these motors usually?

 

[Dukedog]

25 is a hot rod setting... 21 like chris says is good ta go.. also after ya get it runin' at home take it to tha lake.. in tha water, in gear set idle timin/speed/rpm with idle timin' screw to what ever makes you and tha motor happy.. idle timin' numbers don't mean anything..............

 

[Mybiggles]

Will do thanks Duke. It's on a stand at the moment trying to get it freshened up. Had it running as is though. Took the carbs off to clean and found it was missing a jet . Once I get the carbs\fuel pump sorted im going to confirm timing and then throw it on my boat.