HELP! Issue with Mariner 25 outboard, might need mechanic near Trenton GA!

[wmflyfisher]

Hey guys,

I'm new to the area looking for some help with my 98 Mariner 25 outboard. Motor runs strong but there seems to be a problem with the choke. When the motor is cold the choke doesn't seem to work at all. It's electric start and I have to let it turn over numerous times before it finally starts. Once it's warm it fires up like a champ. Happens every time that I try to crank it cold. I pull the choke and it seems to make no difference. Any help would be GREATLY appreciated!! I'm pretty good with car motors but know nothing about boat motors other than the typical plugs, wires, filters that sort of thing.

I would gladly pay someone to take a look at it as long as it's not a fortune. I'm a Ranger for the DNR and funds don't really run deep in this career! Again, any help would be great. Thanks in advance.

 

[spnplgr]

First, I'd install the correct spark plug for that engine.

Those engines do some strange things from time to time. I saw one that was difficult to start, but performed perfectly the rest of the day. I finally discovered that I had to pump the rubber bulb excessively long and hard to get the engine to start easlly when cold. Once I learned that's what it took, no more starting problem - ever.

Some of these engine are easy to flood. To check it out, try using the choke just a couple of seconds. If that does not work, try the opposite: While cranking the engine, put your hand over the carb opening to block off all air flow, making the mixture even richer.

If none of the above works, I'd get a compression test and leak down test done. An engine that has lost compression is usually very hard to start when cold.

 

[MooreEagle]

Pump your gas bulb more before starting

 

[b.lee]

From what I remember... Those engines don't have the traditional choke, but a primer circuit that shoots a small stream of fuel into the carb throat when you pull the square choke knob. Chances are you have an issue with that primer circuit, i.e. clogged jet, torn/broken diaphragm, etc. Probably not anything that a carb rebuild wouldn't cure. Pretty simple fix and will have you running like a champ again.

 

[wmflyfisher]

Thanks guys. Gas bulb is always pumped to the max before starting and it has the correct plugs. Also, I've tried to use the choke when cranking and it changes nothing. The sound of the motor is the same and everything. I push and pull on the plastic choke knob and it might as well be non-existent. It will start EVENTUALLY.

b.lee - 2/17/2011 8:46 AM

From what I remember... Those engines don't have the traditional choke, but a primer circuit that shoots a small stream of fuel into the carb throat when you pull the square choke knob. Chances are you have an issue with that primer circuit, i.e. clogged jet, torn/broken diaphragm, etc. Probably not anything that a carb rebuild wouldn't cure. Pretty simple fix and will have you running like a champ again.

Thanks b,

This sounds like a possibility but where do I start?? How do I track this problem down of fix it??

 

[b.lee]

Pull the cowl off and look at the linkage that actuates the primer. When you pull the choke knob, it has a finger that presses down on the primer circuit diaphragm. You should hear teh small shot of fuel being pumped into the carb when this is pressed. You should also be able to press the finger down by hand without pulling the choke knob to isolate it further. If you don't hear anything, you have a problem here.

The fix is relatively easy. The kit is $25.

http://www.mercruiserparts.com/Show...11407&bnbr=110&bdesc=Carburetor(20/25/Jet+20)

 

[wmflyfisher]

b.lee - 2/17/2011 10:49 AM

Pull the cowl off and look at the linkage that actuates the primer. When you pull the choke knob, it has a finger that presses down on the primer circuit diaphragm. You should hear teh small shot of fuel being pumped into the carb when this is pressed. You should also be able to press the finger down by hand without pulling the choke knob to isolate it further. If you don't hear anything, you have a problem here.

The fix is relatively easy. The kit is $25.

http://www.mercruiserparts.com/Show...11407&bnbr=110&bdesc=Carburetor(20/25/Jet+20)

Really appreciate that! I'll try to dig into it and see if I can figure it out. Thanks again.

 

[spnplgr]

Does your engine have a primer or a choke?

My friend has a 25 Evinrude that is equipped with a primer. It floods everytime he pumps the primer. He lives about 25 minutes from the lake and has learned to pump the primer just before pulling out of his driveway heading to the lake. Upon arriving at the lake, the flooding condition has cleared up and the engine starts easily. However, if he waits until he gets into the boat on the water and then pumps the primer just once, the engine will not start until about 15 minutes later. It was not like that until he had the carb rebuilt a few years ago. Before the rebuild, he would pull the primer four times and the engine would start right up. I asked him if he ever tried starting the engine without using the primer, just to see what happened, and he said "no". I'll bet it would start right up by just pumping the bulb up real tight.

Try pumping the primer about 15 minutes before launching the boat to see if it works. Also try starting it without using the primer, but pump the bulb very tight. If one of these works, you'll have an idea of what to do to the primer, if anything, to cure the problem.

Good luck

 

[wmflyfisher]

spnplgr - 2/17/2011 11:05 PM

Does your engine have a primer or a choke?

My friend has a 25 Evinrude that is equipped with a primer. It floods everytime he pumps the primer. He lives about 25 minutes from the lake and has learned to pump the primer just before pulling out of his driveway heading to the lake. Upon arriving at the lake, the flooding condition has cleared up and the engine starts easily. However, if he waits until he gets into the boat on the water and then pumps the primer just once, the engine will not start until about 15 minutes later. It was not like that until he had the carb rebuilt a few years ago. Before the rebuild, he would pull the primer four times and the engine would start right up. I asked him if he ever tried starting the engine without using the primer, just to see what happened, and he said "no". I'll bet it would start right up by just pumping the bulb up real tight.

Try pumping the primer about 15 minutes before launching the boat to see if it works. Also try starting it without using the primer, but pump the bulb very tight. If one of these works, you'll have an idea of what to do to the primer, if anything, to cure the problem.

Good luck

Thanks for the advice. I just looked and yes it is actually a primer that you pull out, not a choke. Isn't it sort of the same thing?? I always pump the bulb up as tight as I can before I try to crank it and then pull the plug/primer. It's always just acts the same way. Turns over and over until it barely starts to run. I have to keep pushing the button once it finally fires up til it will run on it's own. Everything's good to go after that.

 

[spnplgr]

A primer and a choke are different. A choke is the device that closes the "butterfly" or throttle plate in the throat of the carb when the engine is cold. In the closed position, most of the air flow into the carb is blocked, resulting in a very rich condition that is conducive to helping a cold engine start. A primer actually squirts a shot of gasoline into the throat of the carb resulting in a very rich condition that is conducive to helping a cold engine start.

Some time ago, on a bright sunny day where I could see up inside the carb throat of a 30 HP Johnson, I could actually see a small stream of gas and the resulting mist when I pulled the primer.

You wrote: "keep pushing the button once it finally fires up til it will run on it's own." I don't completely understand this statement. If you mean it finally starts but will not continue to run unless you continue to pump the primer, you most likely have a problem with the carb itself, not the primer system. If that is the case, I recommend you rebuild the carburetor. However, it is also possible that the problem is electrical and not the fuel system, so you'll have to check out both systems. It may be less expensive to have a professional identify the problem instead of throwing parts at it.

 

[wmflyfisher]

spnplgr - 2/19/2011 1:40 AM

A primer and a choke are different. A choke is the device that closes the "butterfly" or throttle plate in the throat of the carb when the engine is cold. In the closed position, most of the air flow into the carb is blocked, resulting in a very rich condition that is conducive to helping a cold engine start. A primer actually squirts a shot of gasoline into the throat of the carb resulting in a very rich condition that is conducive to helping a cold engine start.

Some time ago, on a bright sunny day where I could see up inside the carb throat of a 30 HP Johnson, I could actually see a small stream of gas and the resulting mist when I pulled the primer.

You wrote: "keep pushing the button once it finally fires up til it will run on it's own." I don't completely understand this statement. If you mean it finally starts but will not continue to run unless you continue to pump the primer, you most likely have a problem with the carb itself, not the primer system. If that is the case, I recommend you rebuild the carburetor. However, it is also possible that the problem is electrical and not the fuel system, so you'll have to check out both systems. It may be less expensive to have a professional identify the problem instead of throwing parts at it.

Thanks spnplgr,

I meant that I keep pushing the starter button and it keeps turning over until it finally starts. Once it starts it sounds like it's flooded. Idles low for less than a minute or so then it sounds fine. I just let it warm up after it finally starts for a few minutes and it's good to go for the rest of the day.

I would love for someone to take a look at it but where do you recommend that's fairly close to me (Trenton, GA)? I don't mind taking it somewhere 30 mins away (one way) but an hour away would be a pretty good drive. Any recommendations?

 

[spnplgr]

From what you describe, it sure sounds like a flooding condition to me. As I wrote earlier, simply prime the engine about 15 minutes before attempting to start it. If it starts easily, a flooding condition would be confirmed. Then, all you have to do is experiment to determine what is needed to start the cold engine. Could be just one or two pumps of the primer or perhaps none at all. Try all combinations.

Good luck

 

[wmflyfisher]

spnplgr - 2/21/2011 12:02 AM

From what you describe, it sure sounds like a flooding condition to me. As I wrote earlier, simply prime the engine about 15 minutes before attempting to start it. If it starts easily, a flooding condition would be confirmed. Then, all you have to do is experiment to determine what is needed to start the cold engine. Could be just one or two pumps of the primer or perhaps none at all. Try all combinations.

Good luck

Thanks. By "prime" do you mean pump the bulb on the gas line up or pull the primer plug out?? Am I supposed to push and pull the primer in and out or do I just pull it out once?? Sorry for the confusion. I thought to prime it using the plug you just pull it out once until it fires up then push it in.

 

[spnplgr]

By "prime', I mean pull the primer button. My freind pulls his primer four strokes (gives the carb four shots of gas) before he pulls out of his driveway. Twenty minutes later, he launches his boat and without any more priming, the engine starts right up. Of course, he pumps the gas line bulb up tight also.