sluggish and bogged down

[Br14n]

Ok all you Mariner ninjas, got a bit of a conundrum.

Got an 86 BassTracker with a 50hp '86 Mariner on it. S/N A926072

This boat has been in my family for since 1986 so I know a few of the tricks to get her going, but this one has me stumped. I'll give a little back story.

Got this boat and motor last October. Had been sitting for about 2 years. Totally redid the interior carpeting and decking. New trolling motor, new FF, etc. When I first got it the motor would not start. After some new spark plugs and cleaning of the fuel lines and filter finally got her going. Sat for the winter until last week I put her on the water.

The problem I'm having is when I start the engine at the ramp I was have to throttle-only it up then start it. Fires every time and has been that way since I can remember. After the initial start never had to do it the rest of the day. Pain in the ***, but workable.

Now the issue I'm having is when sitting at idle, or cruising at no wake speed, it will sputter, bog down and eventually die. Almost as if it is not getting gas. If I feather the throttle I can keep it running without it dieing. If it does die, I have to do the throttle-only start and so on.

Once I get passed the sputtering I can go WOT with no problems at all. Runs like a champ, never sputters, bogs, dies, nothing. Had her on the water 3 times so far this spring with same results every outing.

I've replaced all fuel lines. Replaced primer bulb. (both were showing their age; cracking, splitting, general aging) Cleaned fuel filter. Run seafoam through it. Run stabil through. Sprayed some gumout on the carbs.

Any ideas? Thanks guys.


Brian

 

[MH Hawker]

Re: sluggish and bogged down

Run a fuel system cleaner through it like sea foam, you stand a chance of it cleaning out the carb. IF that dosnt fix it then a carb rebuild is in order.

 

[Br14n]

Re: sluggish and bogged down

Thanks Hawker.

I've run about 4 gallons through the engine this spring so far. Had seafoam in entire time. Will more hours help? Is it possible I need to add more? Is there such thing as to much seafoam? Harm the engine?

Before I pay someone to rebuild the carbs, anything else it could be? Fuel pump?

 

[MH Hawker]

Re: sluggish and bogged down

You may have a fitting sucking air.

 

[Br14n]

Re: sluggish and bogged down

You may have a fitting sucking air.

This would be a fitting in the fuel lines? Just 2 days ago I replaced all fuel lines. Had this issue previous to the replacement and after. Would the excess air not affect it at higher rpms or wot, but just low idle?

 

[racerone]

Re: sluggish and bogged down

Step # 1 on an outboard like that is a compression test.----Then you check for spark as follows.----Rig up a tester to force the ignition to jump a gap of 7/16" on each lead.-Does it jump that gap , yes or no.

 

[Br14n]

Re: sluggish and bogged down

Step # 1 on an outboard like that is a compression test.----Then you check for spark as follows.----Rig up a tester to force the ignition to jump a gap of 7/16" on each lead.-Does it jump that gap , yes or no.

Ill see if I can find a compression tester for cheap. "rig up a tester" can you elaborate slightly? or greatly even. I'm not mechanically declined, just new to the marine engine, and motors in general.

I'll get this stuff done asap and report back with my findings.

 

[Br14n]

Re: sluggish and bogged down

Got my hands on a compression tester and spark tester.

Compression was ~140-145 on all 3 cylinders. Had good spark on all 3 also.

After testing these I fired it up on the muffs. I immediately had fueling pouring down into the splash well. Turned it off to inspect.
Removed the air box and filter and tried it again. Fuel was coming out of a small hole on the lower carb. Motor would not idle without dieing. When I revved it up to keep from dieing fuel literally shot out of the same hole.

This is a new problem I have not encountered until today.

In the 3rd picture you can actually see the fuel pouring out.

Ideas?

 

[Big Fish Billy]

Re: sluggish and bogged down

Sounds like your float and needle aren't regulating the fuel for that carb, a cleaning is in order, likely the others aren't far behind. At WOT you're using up the fuel that's flooding by the needle, at idle it's flooding out that cylinder.

 

[Br14n]

Re: sluggish and bogged down

I let it sit for a while then tried to start it again. Good news: no more fuel fountain. (edit: because i forgot to reconnect the fuel line, so no good news at all) Bad news: will not idle at all, not even pretend.

That makes sense to me. Don't know I am capable of doing that maintenance myself. Might have to take a trip to the shop.:blue:

Thanks BFB

 

[Br14n]

Re: sluggish and bogged down

well I took the carburetors out. separated them from one another.

btw its really annoying when my pictures fail to upload.....

anyhow... what should I be looking for and what should I be trying to clean?

I removed the bowl and they look very clean to me. just bare metal. no gunk, sludge, anything like that. The floats however, are a pale orange color and they appear to have small pieces missing from them the needle looks clean.

I'm positive I will have to replace those. Anything else I should be looking for? Any advice?


Thanks


Brian

 

[Big Fish Billy]

Re: sluggish and bogged down

As you might imagine, if they don't float properly in the bowl, they will not regulate the fuel properly...ethanol likely has taken it's toll. Be sure everything is clean, all the orifices are clear, and sounds like you need some new floats....

 

[Br14n]

Re: sluggish and bogged down

figured out why my pictures weren't uploading. Guess the file size is 2mb.

Here is the pictures of the carburetors.

and a closeup of each

 

[Br14n]

Re: sluggish and bogged down

I made a run to my local boat shop to acquire some new floats and gaskets for my carburetors. While I was there I also got a new impeller and and gaskets for my lower unit. The shop only had 1 kit for the carburetors, bummer. I think only one was failing, but might as well change both when I have it pulled apart, right? Bought the one they had and put in an order for the second, which should arrive Wednesday or Thursday.

Arrived home and open the float kit only to discover it was broken. Just not my day I guess. Ran back down to the shop, showed them the broken piece, took it back without question and added a 2nd float kit to my order.

So Thursday I'll be installing the new floats and gaskets. Any tips, tricks, advice, or anything I should be looking for?

Thanks for all the help guys, very appreciated. Want to keep everyone following updated on the status.


Brian