New to the Mercury Mariner forum since purchasing a 25hp Mariner (1991 era) that ran rough. Cleaned carbs and now it idles and runs steady (success!), but wanted to make sure the timing is correct and sync'd correctly. Purchased the factory service manual and am following the "WMC" type carburetor procedures.
Step 1: Adjusted carbs properly.
Step 2: Full throttle timing adjustment was correct as the timing pointer lined up with the 3 dot mark on flywheel.
Step 3: Adjusted carburetor throttle cam as described in manual.
Here's where I run into my issue:
Step 4: Throttle Pickup Timing Adjustment: Manual says to advance throttle lever until the 2deg. ATDC timing mark (one mark to the right of the single dot) on the flywheel lines up with the timing pointer. This is impossible for me since at idle the flywheel is already past or to the left of the single dot about a half inch. As I increase the throttle, the pointer gets closer and closer (further left) to the 3dot mark until it gets to WOT. Didn't know what to do from here so played with the idle speed adjustment screw to see if that would get the pointer closer to the single dot. This seemed to move it a little bit but not nearly enough to get one mark past the single dot....Tried again with the throttle link rod disconnected from the cam but this didn't get me close either.
Am I missing something here?? Is there an adjustment I skipped?? The manual doesn't address what to do in my situation.
Step 1: Adjusted carbs properly.
Step 2: Full throttle timing adjustment was correct as the timing pointer lined up with the 3 dot mark on flywheel.
Step 3: Adjusted carburetor throttle cam as described in manual.
Here's where I run into my issue:
Step 4: Throttle Pickup Timing Adjustment: Manual says to advance throttle lever until the 2deg. ATDC timing mark (one mark to the right of the single dot) on the flywheel lines up with the timing pointer. This is impossible for me since at idle the flywheel is already past or to the left of the single dot about a half inch. As I increase the throttle, the pointer gets closer and closer (further left) to the 3dot mark until it gets to WOT. Didn't know what to do from here so played with the idle speed adjustment screw to see if that would get the pointer closer to the single dot. This seemed to move it a little bit but not nearly enough to get one mark past the single dot....Tried again with the throttle link rod disconnected from the cam but this didn't get me close either.
Am I missing something here?? Is there an adjustment I skipped?? The manual doesn't address what to do in my situation.