Tracker/Merc 90 hp stalling help needed

[fichrman2]

Trying to help the neighbor with his boat, the issue is- At idle out of gear the motor has a miss or hic-up. Once every 5 seconds or so it would act as though it lost spark, and miss and then idle fine again, but cycling in this manner. The problem has become more pronounced and now it will stall at idle out of gear, in most cases when you put it into gear it will also stall. When you can manage to get a rev and get it on plane, it seems to run fine. I pulled the carbs off today and made sure there was no debris/trash in the bowls and also removed and cleaned what I assume were the low and high speed jets as well as making sure the inlet line was clear. Also replace the plugs (the old ones were slightly worn) repaired a poor plug wire at the coils and verified proper connections at the coil packs. This boat gets used a TON and I really didnt expect to find anything in the fuel- but had to be sure, Im at a loss here guys and could use a hand.

Went a little further this eve. Compression @150 lbs across the board and spark appears very strong on all 3 holes spinning over with the wire grounded. I gotta think I missed something in the carbs - anyone ????


Andy

[j_martin]

First the carbs need a good cleaning. There are a bunch of small passagways that deal with idle, most of them under the top plate.

While they're off (again) take a peek at the reeds and be sure that they seem to be seating OK. If in doubt, pull the reed block and check them out.

Be sure all the bleed hoses are routed correctly, in good shape, and the check valves are OK.

What you describe sounds like chit in the idle circuit of one or more carbs.
or could be floppy reeds.

hope it helps
John

[fichrman2]

Thanks John, you refer to check valves- and bleed hoses. Im a little lost there, there is one solinoid type valve and a vacume tube that runs from the top carb of the 3. ?? Sorry for the ignorant response- slap me , Im a newb....

Andy

[Tom Foley]

Wake up son !!:thumbsup::cheers::cheers::cheers::cheers:

[fichrman2]

Hey Tom. :)

[j_martin]

Thanks John, you refer to check valves- and bleed hoses. Im a little lost there, there is one solinoid type valve and a vacume tube that runs from the top carb of the 3. ?? Sorry for the ignorant response- slap me , Im a newb....

Andy

No slap, just a gentle nudge.

On some engines there are lines that bleed off gas puddles where they occur, usually near the reeds. They have check valves in them. You need to look up your serial number 90 horse in the parts system. It's called the bleed system.

When bleed hoses are mis-routed, cracked or broken, or the check valves are bad, it can cause wierd things to happen at idle.

hope it helps
John