I have a 93 model 115. On my first trip out the motor would only run if the bulb was constantly pumped (It sat for six months). It used a lot of gas. I have since rebuilt the fuel pump and cleaned and regasketed the carbs. I can get it running but to keep it running I have to constantly keep the choke on, and pump the bulb every few seconds. Anyone have an idea what to do next???? Please advise.
Ensure those carbs are spotless, blow carb cleaner and compressed air thru all passages.
Floats set carb inverted dead level with carb base.
Throttle arm removed adj carb linkages, loosen all, flex/rotate and release each carb to seat throttle blade then carefully, gently tighten linkage soas when actuated ALL carbs respond. reattach throttle cam and adj rollor to pickup line.
Idle adj screws, start at 1 1/2 turn out, adj running for best idle speed + 1/4 turn fat
Adj idle speed w/ base timing adj screw
How oldl is the fuel in the tank?
How old are the plugs?
I run NGK BPR8HS at .032" gap far cheaper than the precious metals and I change every year.
Well, when I cleaned the carbs I made sure all passages were clear. I used carb cleaner and replaced the gaskets. The top two carbs have adjustment screws on the sides, I think these are idle adjustments and I have moved them around a bit. Which ones are the timing adjustment screws???
The fuel, tank, primer bulb are new. The plugs are ??????? but I pulled them off a few days ago to do the compression check (OK) and they looked to be in good shape. I did not measure the gap.
The carb linkage does have the carbs responding in unison.
Those carbs don't have idle screws. That's the idling mixture screw. Follow CharlieB there.
Then follow the rest of CharlieB's advice. Also try running the motor without the cowls on.
But at a guess I'd suspect a hole in one of the fuel pump diaphragms. Does the bulb ever get hard if you pump it while the engine is off?
You've given us two very iimportant clues as to what is wrong.
1. you have to keep pumping on the primer bulb.
Generally, that is a definate sign that the fuel pump is NOT pumping fuel, you are pumping it manually. Either there is a fault within the fuel pump OR an air leak INTO the line AFTER the bulb and before the pump.
2. You have to keep choking it to stay running.
if this is at an idle, then the top two carbs with idle mixture screws on the side, near the top, are not passing enough fuel
. Turn the screws IN clockwise gently until they stop, DO NOT force them. Back the mixtures out 1 and 1/2 turns. This should be enough fuel to start and run, adjust running at an idle to 'best' idle speed then back out 1/4 turn more if running on a garden hose, only 1/8 turn if the boat is in the water.
Mariner 115 2+2 fuel problems
Re: Mariner 115 2+2 fuel problems
Linear Mode
