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Difficulty in keeping motor running when starting cold

G

golden eagle

New member
Hi guys, with your formidable knowledge of outboard motors I'm sure you'll crack this one in no time. I have a 1995 90 hp Johnson that runs great, I've had it now for twelve years and it's always been difficult to keep it going when started cold. The VRO is disconnected and oil is mixed with fuel in tank. The primer solenoid works good, the primer bulb gets hard when compressed, can hear the fuel circulating to the fuel system. But, I need to start it at least six or seven times before it keeps running without stalling even though it starts in a few cranks every time. I need to keep in fast idle a few minutes before I can take off at increased throttle speeds. And upon starting it does smoke a lot because of oil accumulated in the cylinders, mixture is 50:1. I'm under the impression that motor is not properly fed with fuel upon cold starts, but can't seem to pinpoint the problem, what would be your guess? This problem makes it look and smell like a crappy motor but it isn't. Thanks for your suggestions.
 
Post your starting procedure with some detail.-------These motors in good condition start right up first try.--Usually have to push the key in a few tiomes if it falters when still cold.-------Thermostats installed and working properly ??
 
I've just checked the carb mixture adjustment, the needles were out between 5 and 6 turns, the service manual specifies that the initial setting is 3 turns off the seat. So I turned them in to 3 turns off and I am going fishing tomorrow and I'll bring a screw driver along to fine tune the adjustments on the 4 carbs. As for my starting procedure; I fully open tank vent, pump primer bulb till it's hard, press in ignition switch for a few seconds and engage starter. Now Racerone when you say push the key in a few times do you mean before engaging the starter or once it's running. Does the primer solenoid inject fuel once (like a primer bulb on a lawnmower)when key is pushed in or does it supply a continuous flow of fuel as long as you hold the key in? Because I have never held the key pushed in once the motor is started, it stalled and I would start the procedure over again, now don't tell me that all I had to do was hold the key pushed in to keep the motor running? Although it would be simple way to solve what I've been putting up with for the last 12 years! Really appreciate your sharing of knowledge. As for the thermostat it was ok 11 years ago when the engine was rebuilt, it's not overheating and if it was stuck open could these 6 or 7 failing starts make a difference in engine temperature to the point of getting the motor to run properly, because once it's running it seems to obtain running temperature and good running performance in only a few minutes of cruising. Thanks again.
 
Here are some facts !----For starting the throttle must be advanced for fast idle.--------The electric primer only works when there is fuel pressure on it.----When you push the key in before cranking that pressure bleeds off quickly.------That pressure comes from the manual fuel pump ( primer bulb ) and from the engine fuel pump when it is cranking.----When the key is pushed in and there is pressure, a constant stream of fuel is injected for start-up.----------The key must be pushed in and held in when cranking. After the motor starts you may have to push the key in momentarily to keep it from stalling till it warms a little.
 
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The electric primer is not a " pump " is is merely an electric valve.------If key is pushed in and held in the valve stays open and fuel is squirted in due to pressure from either someone operating the manual pump ( primer bulb ) or the pressure from the engine fuel pump when the motor is cranking.
 
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Well what do you know, I kept it going first shot by using the electric primer, it replaces the mechanical choke system, DUH, I should of thought of that before. By reducing the air fuel ratio my idle speed is down some so now all I have to do is adjust the Idle speed and mixture on water, I did have good intentions but I didn't want to bother my guest with mechanical adjustments, so we fished. I'll go out by myself someday and proceed with the adjustments and I'll let you guys know how it all worked out. Now KIM do you think that replacing the thermostat and impeller is preventive maintenance and what is your opinion on the lifespan of these two parts? Thanks again Kim and Racerone.
 
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