1969 85Hp V4 sputtering misfiring in-gear idle speed only

[Drymite]

The engine has 125 compression on all 4 cylinders. It starts right up from cold and warm. I noticed today when i was getting back to the docks when at low rpms im not sure if i was going too low in the throttle rpms since i have the hydroelectric shifter and it does it once i pull it back past the "start " indication it seems to slightly misfire and shake..... brand new plugs. I haven't checked my carbs.
I noticed my engine is missing low speed adjustment connection thats on the opposite. Side of the manual choke . The owners manual doesn't really show anything about it but to grease the connections.
Am i going in a too low rpm when pulling past the "start "?
I havnt checked carbs since. I bought it in april. It was winterized. And it didnt take long to get it running ofcourse since i dealt with a low compression force 85 before. first thing i checked was compression at cold and warm... changed the impeller and gasket. Flushed the gear oil and i put Type c fluid That hasnt showed sign of mixing after 15 hrs of use.
Spark on all 4 cylinders
Im currently running it on 91 with XD30. I just got a gallon of XD100 since the price difference isnt much and i read that i can use the xd100.
The engine runs fine at WOT and regular speed.
I do not have the Tachometer wired. Since im not sure if its the lone grey wire thats coming out the control box.

 

[jimmbo]

XD 50 may be a Better Choice, as XD 100, was engineered for use in DI Engines and used to have 'Not Recommended' in Premix Motors on its Label. It may have contain Additives that would Inhibit it from Mixing with Gas.
Inside the Air Silencer, there was a Linkage that Ganged the 4 Idle Mixture Needles together, and was linked to an External Adjustment Lever. It allowed a very limited Adjustment, and each Carb had to adjusted Separately prior to being connected.
You might have to adjust the Idle Speed, it should be about 600-650 in gear. You might have to adjust the Throttle Cable Length as well.

 

[Drymite]

XD 50 may be a Better Choice, as XD 100, was engineered for use in DI Engines and used to have 'Not Recommended' in Premix Motors on its Label. It may have contain Additives that would Inhibit it from Mixing with Gas.
Inside the Air Silencer, there was a Linkage that Ganged the 4 Idle Mixture Needles together, and was linked to an External Adjustment Lever. It allowed a very limited Adjustment, and each Carb had to adjusted Separately prior to being connected.
You might have to adjust the Idle Speed, it should be about 600-650 in gear. You might have to adjust the Throttle Cable Length as well.

I see i didnt notice that its not a tcw-3 oil thanks for clarifying i haven't ran it yet or even open the gallon so i can return it. And get XD50....
how do i adjust the idle on the 1969 Is what you just mentioned in the air silencer ?

 

[jimmbo]

Technically, it exceeds most TCW-3 Specs by quite a Margin. There was never a TCW-4 spec, but TCW-3 oils, even the best, weren't blended to deal with the Combustion Products unique to DI Engines. So OMC and Mercury eventually developed Oils that were Specific to DI Engines, and since they weren't intending those Oils for Non DI Engines, likely felt there was No Reason to have them TCW Certified. But since these oils weren't intended for regular 2 Strokes, the requirement for staying mixed with Gas, wasn't part of the Formula.

I will have to find the info regarding the Idle Mixture adjustment for that motor.
The Idle Speed Adjustment is on part of the Linkage, and it limits the amount of Timing Retardation. The Carbs are to be Fully Closed at Idle, and stay closed for quite a while as the engine is speeded up.

 

[jimmbo]

 

[Drymite]

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Thank you