[dargel167]

My 89 Mariner 100 hp was not running right & also dumping fuel out the back.I put a new fuel/water filter,nylon fuel filter,new plugs, & rebuilt the fuel pump.Put new fuel hoses on also.Now it will not idle.You start it up & it idles @ 1200 rpm for maybe 30 40 secs & then surges to 1800 rpm & coughes & drops to 1200 rpm then back up to 1800 rpm & in one second it repeats itself.I have never put a carb kit in it.maybe I need to!I would like any help on this problem.I have always used premium gas.HELP...............THANKS!

[CharlieB]

Premium fuel is not required, you may not realize any benefit from using it other than a lighter wallet.

The addition of a water seperator and another fuel filter as good preventative maintenance, however it may have been just a little too late, the carbs need attention. I suspect that if you look down the carb throats with the engine turned OFF, and squeeze the primer bulb, you may see fuel leaking into the engine.

You should order the correct service manual and carb kits for your model motor.

Clean them thoroughly, pay particular attention to the small passages, after soakiing in cleaner blow compressed air through ALL passages to ensure they are perfectly clean.

Install all the new parts that come in the carb rebuild kits for your model #. Pay close attention to the float setting.

Reinstall, synch the carbs and link them to the throttle and timing levers according to the directions in the service manual.

[dargel167]

Thanks for the advice CharlieB.You were right,the #4 carb. throat had fuel standing in the bottom of the throat.I have a factory manual & going to order 4 carb. kits & fuel inlet needles.No more premium fuel for me.When I am through I will post the results................THANKS again...............dargel167

[dargel167]

Sorry about getting back so late CharlieB.I rebuilt the carbs & put new fuel & oil lines on.The engine already had a water/fuel seperator on it.The engine still does the same thing but not nearly as bad.I think it will work itself out of it after running it for a while.Other than that it runs like a new one.Thanks for the help & sorry about the lateness of my reply.THANKS AGAIN. dargel167