98 115 cold start question?

GatorMike

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I have a 115 that has always started on one or two turns of the key in the past. Reciently it just doesn't seem to want to start cold. Once it has warmed up it starts fine. Anyway I don't think the problem is compression. For years all 4 cylendars have read within 5 pounds of 120 psi. I have had a slight drop in 2 of the cylendars to around 115 psi the last couple of times I checked it but this would still be way within the recomended tolerances 2 at 120 and 2 at 115. Anyway I am starting to wonder if the primer solenoid is working. Is there a way to check this? I was thinking maybe if I pumped up the ball then pushed in the key for a few seconds then pulled a plug would that tell me anything. Like maybe the plug being wet or the smell of gas might tell me it was working. Would that work? Any other suggestions would be greatly appreciated.
 

tashasdaddy

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Re: 98 115 cold start question?

pull the small hose off the carb. pump up, then turn key to "on" and press in on the key. gas should shoot out the hose.
 

Chris1956

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Re: 98 115 cold start question?

Mike, The primer solenoid may not be working. I think it should spray fuel into the airbox, when the key is pushed in. You might check it.
 

tashasdaddy

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Re: 98 115 cold start question?

it does not spray into the airbox, it sprays behind the butterfly directly into the intake. this enrichens the volume of fuel, to air mixture. the easiest way to tell if it is working is remove the hose.
 

GatorMike

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Re: 98 115 cold start question?

Thanks guys, I have one more question. Apearantly the primer is working fine. I pulled the hoses off each carburator and had my son turn the key on and push it in and got a good squirt out of each hose. I plugged them back in and tried to start it and it just turned over and wouldn't fire. Then I sprayed a quick shot of starting fluid in the carbs and she ran on the first turn of the key.

Sounds like I have a fuel problem somewhere I just don't know where to start. It seems to me that that shot from the primer should have made it fire if a 1 second blast of starting fluid did the trick. Keep in mind the boat runs fine once started that first time and restarts with one turn of the key once it has started once.

Where would you suggest I start under the conditions I have described? Fuel Pump? Fuel lines? Carburator rebuild? I'm pretty sure it is fuel related because I re checked the compression and the numbers were 120 122 115 & 115.
 

iwombat

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Re: 98 115 cold start question?

My guees is a carb rebuild, but let's get some better facts before going down that road. How does it idle once it starts up?

Lose the starting fluid, it's murder for outboards.
 

GatorMike

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Re: 98 115 cold start question?

It idles fine and runs fine. I took it out fishing yesterday. Took several minutes of cranking and primeing to start it the first time the rest of the day it idled just fine, never stalled and restarted everytime.

I'm thinking maybe since the primer seemed to squirt with the hoses pulled off the carburators maybe the holes it sprays into the carbs through are clogged. Maybe I'll start by spraying a little carburator cleaner in those ports?

I do want to get this problem solved because years ago I had a Mercury that was a slow starter and I remember how that problem wears on the battery, starter and entire system.



On the starting fluid issue, I know the issues with starting fluid in a 2 cycle and I would never keep spraying it into the carbs but I don't think a quick 1 second spray to see if she will fire would hurt anything. If I were doing anything more than that I would use a spray bottle of gas and oil mix.
 

SKEETR

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Re: 98 115 cold start question?

You are starting it at about 3/4 throttle right?
 

ezeke

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Re: 98 115 cold start question?

Are you pushing the key in while you are cranking on a cold start?
 

Chris1956

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Re: 98 115 cold start question?

Does that motor use battery voltage to supplement the stator voltage when cranking? I think I read that my '98 V6 has that feature, which is intended to give a hotter spark. Your motor could be suffering from a weak spark.
 

GatorMike

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Re: 98 115 cold start question?

Yes I am starting it at 3/4 throttle also have tried full throttle. Yes I am pushing the key in while cranking have also tried before cranking.

As for the question about the spark, I am not sure if my motor has that feature but if so you may be on to something. I noticed Tuesday when I had it out my fishfinder gave me a low voltage message on the screen and I looked at the volt meter and she was putting out almost 0 volts so I retightened the battery cable and it came back up to just under 12 volts. When I get home this afternoon I think I will clean all the connections just to be sure.
 

GatorMike

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Re: 98 115 cold start question?

The more I think about this the more I think it may be a spark problem and not a fuel problem. Yesterday that one quick shot of starting fluid and she fired right up. Seems once the motor was running she didn't even sputter. I bet I am not getting much spark off the battery but once she fires the stator is supplying all the spark she needs to run.

If it turns out to be that simple I owe you one. Thanks.
 

Chris1956

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Re: 98 115 cold start question?

Mike, OK, I have remembered some more details about the spark booster.

See if you have a wire on the same solenoid connection stud as the starter cable. This wire should run to the ignition powerpack. When the key is turned the solenoid closes providing +12V to the starter and the powerpack. This is the spark boost when the motor is cranking.
 

GatorMike

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Re: 98 115 cold start question?

Well Chris, I don't see the wire you are talking about but reguardless you put me on the right track. I cleaned and wire brushed the electrical connections and she fired right up. Until you brought it up I would have never guessed this was a spark problem. I would have been working on this one for some time. Thanks for the help.
 
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