A quick question regarding my Mariner 45hp. issue

[JimBuck]

For the last 3 weeks. My 87' Mariner has been acting up. When sitting for a while....the engine has a hard time turning over. After cranking for sometimes 15 seconds it will SLOWLY start to putt into gear and turn over. It's fine and operational then and if I start it up again in less than an hour it turns right over. But a few times while running at slow speeds it putt's out like gas flow is stopping. I'm wondering if it is something that has to do with air in my gas or inconsistent gas flow to my motor. Any suggestions on narrowing down the problem?

[BoxMN]

This sounds real close to what my '96 25hp Evinrude is doing. From discussion here, as close as I can tell I will need to rebuild or at least clean the carb this fall.

I went through the normal "get new fuel line and bulb" and new gas and all the normal stuff, and it still is doing it. It is like what happened to my '94 Honda Magna a couple years ago, I think the carb just gummed up - after cleaning it runs like new again.

I would start with a brand new "merc" brand fuel line and bulb. The kind you get at FF or Wally world are far inferior, I know that one from experience... doh.

Good luck, those 45/50 merc/mariner motors are great, we have a '82 that we have not touched other than impellors so far, and plugs.

[JimBuck]

Carbs eh? That doesn't sound too good. The engine has been excellent for me and I've never had a problem until now....I will try out the fuel line and bulb and see if I can narrow it down from there. How did you go about cleaning your carbs a few years back BoxMN? I think I've only used a solution that you add to your gas and that seemed to really perk the engine up.

Cheers,

-Buck

[BoxMN]

Yeah, do the cheap and easy things first, the fuel line and bulb.

For the carb cleaning, either bring it in to mechanic, or you can try yourself. I brought my bike into a mechanic and the job was like $500 - but that is 4 carbs on that bike, and I got a deal for doing it in Feb... nice. I then had to take off my carbs on the magna myself to find a fuel leak (old gasket) and that was a bigger job than any outboard carb, that I can think of, at least till you get to big v-6's or soemthing...

For my 25hp and when I get to the 50hp merc, I will just do it myself. It really isn't that hard, and after doing one I think it will be easier. Just get carb kit from dealer and ask for a bit of advice, and then go to town! I am doing my 25hp this winter in the garage.

I think the 45 mariner has two carbs, each supplying two cylinders, but other might know for sure and can also let us know if I am blowing smoke anywhere.... as I am not in any way a mechanic. But over the years I have serviced my own motors more and more, and for the common stuff they are actually pretty straightforward and not too bad to do, as long as you have the space, time and tools.

When I say clean the carbs, I am not talking additives, but actually taking them off, putting in new gaskets, cleaning out the bowls and new jets, etc. Sounds more complicated than it really is, though. But it could get messed up if you don't do it right, but IMHO, don't let that scare you. They are less complicated once you get one apart. Or else a couple hundred bucks will probably get the job done with a real mechanic

Good luck.

[Surface Tension]

Are you choking this for cold starts?

[JimBuck]

Cheers Box. Thanks for the knowledge. I think I'm going to look into the fuel line and bulb here tomorrow and take things from there. Replacing those wouldn't be a bad idea anyways since my bulb is beginning to crack.

Surface Tension. Yes sir, I am choking on the initial attempt if it's been sitting for more than an hour.

[Surface Tension]

Like Bob said check the easy stuff first.

One more question, are you priming up the bulb before cold starts and after an hour of sitting is the buld still firm?

If the answer is yes, with the other info you provided, change the spark plugs.

[raymondk]

i have the same motor I also had the same problems starting when it was cold and when it sat for awhile. you should go through your carbs you might have a sticking needle take the cover off and see if you have any gas leaking the bottom of your carbs should be dry. For your plugs they have ones that do not have to be gapped there is no tip on the right ones . carbs are very easy to do just take your time . Your motor might be flooded that is why it is hard starting.It might just be leaking alittle so you woundn't notice it when it is running

[JimBuck]

Surface, the bulb has been losing firmness after about an hour of sitting. I'll check out the spark plugs as they could be changed anyways.

Raymond, good to hear someone else has similar issues. You mentioned a "sticking needle" can you elaborate? I have noticed traces of gas in the water on occasion. You also suggested plugs that don't have to be gapped? Can you explain? Outside of routine maintenance I don't know much about it.

Thanks again guys!

[BoxMN]

The plugs simply don't have the little "curl" piece of metal. They just don't look the same for this motor as your normal car or other plug, so no need to worry about gapping them.

The needle is just one component of the carburator. Most likely, if it is a carb issue, is that you either have some debris in there, or more likely with this age motor you have some build up of "crud" or varnish that either clogs a jet or prevents the needle from doing its job.

The other guys know real terms and how to do it, but in a nutshell it just needs a simple cleaning by hand Nothing some small tools and carb cleaner and a toothbrush can't fix!

[JimBuck]

Excellent. Again, many thanks for the responses BoxMN.

Cheers,

-C

[JimBuck]

Just dug around and exposed the engine after work today....I did notice some moisture or gas buildup near the front part of the engine. Is this a sign of my carb leaking?

[marine_man]

It could be, it could also be from priming your motor with the motor tipped up, and gas running out the front of your carbs.

Go over the fuel line all the way to where it connects to the fuel pump, see if there are any cracks, evidence of leak (dust / dirt buildup) and go from there.

If it loses prime after an hour it sounds like a leak in the hose or a carb job needed.

marine_man

[wastewaterguru]

That fuel filter looks a bit aged as well. I would certainly think that a clogged fuel filter or weak fuel pump would cause those symptoms as well.

[JimBuck]

Thanks again guys. Just to give an update. I went over the hose this weekend trying to find a leak without any luck. I did notice that when I prime the bulb it barely takes in any fuel? With this problem recently uncovered, it leads me to believe that theres a leak that occurs between my primer bulb and fuel tank? I'm going to head to the shop to see if I can find a new attachment for the gas hose and a new fuel filter.

[marine_man]

I would replace the fuel hose assembly - from tank to motor to remedy all issues there.

marine_man