idle compensator as to timing

Joined
Aug 17, 2011
Messages
6
i have read and wrote down the timing proceedures from the timing and sync of merc inlines posts, but i keep hearing this idle compensator thing coming up. my Q is do i need to do this to go by the timing/ sync proceedures? and if so how do i do it. im not dumb i swear, just ignorant of 2 stroke engines and this engine in perticuler. its all deffenately been a learning expirience for me, so much differant than 4 stroke at what im some what profitiant at! thanks every one you all been alot of help!
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,036
Re: idle compensator as to timing

Not to be flippant, but we are ignorant of the year and HP of your motor. Some motors do not have idle stabilizers.

BTW the only difference in ignition between 2 cycle and 4 cycle is the number of times/rev that the plugs fire.
 
Joined
Aug 17, 2011
Messages
6
Re: idle compensator as to timing

oh sorry its an 87 115 hp mercury distribitorless. i got it to run in the water but still wont idle low, @ 1000 rpms. with throttle linkage unhooked @ 800 rpms it stalls when put in gear and on idle stop,and does it @ 1000 also. hole shot seemed better than ever to me but i bought it used and things seemed tamppered with. and stalled twice going from WOT to N, also ran @ 4500 - 4700 rpms, not sure if thats normal, because i never really thought to note what it ran before i tore it down, to me but no expert, it seems like timeing is still out on the throttle pickup setting, i set it @ 3-4 btdc with cam just touching and opening very slit on carbs. max is set @ 20* btdc seems good there. carb idle screws are set @ 1 1/3 turns out, seems to like it there, the 1 3/4 turns, then in till stumble back out 1/2 turn, plus 1/4 out on all didnt help none made it worse, the 1 1/3 was were they all was before rebuilt, geeeerrrr season will be over before i get this thing right, lol
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,036
Re: idle compensator as to timing

I did not see an idle stabilizer on the parts list for that motor. I also do not think the timing specs you quoted are correct. I recommend you recheck them. I had thought the ADI ignition idle pickup was 4*ATDC. Max timing is likely 21* BTDC.

Normally idle mix screws set at 1-1/3 turns will be too lean to accelerate. I would also check float height and inlet needle valve condition.

So in a nutshell, check timing specs, retime if necessary, reset carb floats if necessary, readjust idle mixture, reset idle stop setting.
 

Gomer50

Chief Petty Officer
Joined
Sep 5, 2009
Messages
507
Re: idle compensator as to timing

I am surprised she runs like that with only 1 1/3 turns out on the carbs (very lean)??.When running right they are closer to 2 turns out.Also runing that motor @ WOT and only achieving 4500-4700 RPM is seriously lugging her,she should be spinning in the mid 5000 RPM range @ WOT.Will cause internal damage...Good Luck and take chris1956 advice..
 
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