1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

[achilles555]

I just bought a 1987 Bass Tracker about a week ago. The motor is a Mercury Classic Fifty 45 HP, with serial number OB161091. The motor has sat for 2 years without being started, so I went through and did the basics. I greased everything with a good mercury grease, replaced the water impeller and gaskets, replaced the starter (it was corroded and bad), checked compression on all 4 cylinders (120 each cylinder), and tested for spark. Everything looks great. I took the boat out to the ramp for the first time today, and fired her up. Started on the first turn of the key and it sounded great. Purred like a kitten. I was pretty excited. Things went downhill from there.

After it ran for a little bit (30 seconds?), it sounded like it was flooding out, then finally died. I tried starting it several times, and noticed a LOT of gas on the water. Turned it over a couple more times...and poof! I had a fire on my hands. After getting that put out, and checking for any damage (which there was none, thankfully) I took the cowling off, and watched the carbs. A thick stream of gas was squirting through the bottom carb every time i turned the engine over, and also when I pumped the bulb. I tapped on the float bowl with the end of a screwdriver, and got nothing.

Seems to me like i've got a stuck float...maybe both of them, and may need a carb rebuild. I really don't know at this point. The carbs are something I really don't want to mess with. My Seloc manual sucks for this motor, and it's hard to follow. The motor is in excellent condition...I just don't feel comfortable removing the carbs.

I tried getting to the bowl to see if I couldn't just remove it and clean it out, but with this motor, it's nearly impossible to get to. I just don't know what to do next.

Does anyone out there have any suggestions for me to fix this thing? Is there anything I can try that might get the float to break free without damaging anything? I think if I could get the float free, I could run a good carb cleanser through the motor in a tank of gas. Any suggestions/help would be much appreciated. AC.

 

[mark_gober]

Re: 1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

I think you may be on the right track. With a flooded float, when you pump the bulb, it'll never float the float and seat. This will allow further pumps to send the fuel out of the carb. I don't have one, but most people I've read dislike the SELOC manuals. My carb was actually really easy to fix. The bowl shouldn't be that difficult to remove and examine...even if you have to remove the carb to do it.


Mark

 

[achilles555]

Re: 1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

hey mark. thanks for the reply. i took a closer look at the carbs and floats this morning. looks like the carbs are going to be really difficult to get to on this little 45 HP Merc. This may be one of Mercury's workhorses, but the design and placement of the carbs certainly doesn't win any "convenience" awards. I think I'm going to let a mechanic do a thorough check and rebuild of my carbs instead of tackling this one myself. For both my sanity...and the health of my marriage.

I found a mechanic that is going to rebuild the carbs for me for between $200 and $250 parts and labor. That seems like a pretty fair price to me, although it is not a marina or a certified tech. Does that seem like a pretty fair estimate to anyone else out there?

thanks a ton. ac.

 

[mark_gober]

Re: 1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

Achille,

It really depends on your situation. Personally, I wouldn't pay someone to rebuild my carbs, but I'm fairly handy with those types of things. I rebuilt mine and I'd never rebuilt a carb before. It was suprisingly easy. I can't speak for your particular motor, because I'm not sure how much of a pain the carb is to get off, but mine was two bolts and a couple of screws. Once I had it in my hand, it was just a matter of removing screws and keeping track of things. If you don't feel like you can handle and you are OK with paying for it, go for it.

Mark

 

[verado7]

Re: 1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

you take the front bracket off to get at the carbs -very easy -i have the same motor - carb kits are only 100 canadian including the fuel pump kit ( recomended) .

 

[cedar creek]

Re: 1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

My problem is very similiar will run under idle for 30 seconds and then I have to increase the rpms to keep it running . will run at higher speeds but floods out at lower speeds leaking gas and if I prime it leaks gas worse which leads to a float problem. Mine is a 87 35 hp, can I remove the bowl without removing the carb itself?

 

[gride830]

Re: 1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

i just rebuilt mine 3 weeks ago on the exact same motor you have.....easy...my only concern was that the rebuild kits i used had a lot of parts, more than i used....figured the kits covered a large array of motors.....you pretty much have to take off the starter and loosen the front plate so that you can bungee it out of your way.....a lot of wrenching but you can do it....had to used a propane torch and bend a cheap foreign wrench the way i needed to get to the nut, bottom carb, left side....really difficult......had to cut off the fuel lines as well to make it easier to remove the carbs.....so i rebuilt teh carbs and replaced the lines abd moved on to replacing the impeller which is where im stuck now.....

took off the lower unit, replaced the impelller, and then installed the lower unit multiple times.....cant get it to come out of forward gear......did somehitng wrong for sure.....might be august before i get my tracker on the water....john

 

[cannonford57]

Re: 1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

cedarcreek,your engine has 1 carb i believe,if so it will be very easy to pull the carb...

 

[verado7]

Re: 1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

87 classic fifty 45hp has 2 carbs and its a 4cylinder
and for the guy that wanted to take the bowl off - that wont help you need to set the floats with the carb upside down and get the float so that its parralel to the base or slightly towards it . and yeah the kits come with alot of parts some are for different versions just match up what comes off your carb and you'll be fine - it's all really obvious when you get it apart and as a tip turn the carb upside down when you remove the bowl and that should keep everything in it's place , also you can dunk your floats in a bucket of water to check for leaks not very common but it happens .

and thriow away the float setting specs that'll drive anyone crazy - merc techs set the floats as i described .

 

[cedar creek]

Re: 1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

I talked to a mechanic and he said it could be bad reed valves, does this seem prabable?

 

[festerized]

Re: 1987 Mercury 45 HP Stuck Float or Carb Problem? Need Some Help!

I finally fixed my classic 50
My motor wouldn?t tach up over 3000 RPMs
At first i had the ethanol blues,? so I cleaned my carbs, put in new fuel pump, new fuel cell, new lines
Motor ran good for about 10 min
Took everything apart 2 more times checking everything
Come to find out the 2 screws on my throttle actuator had stripped out, preventing full throttle
Mercury no longer makes the upper and lower throttle actuator, so I helicaled the screws,
Took a little bit to adjust throttle actuator, but I got it and it runs great
Be careful what you touch, I found out the hard way that 2 different problems produced the same 3000 RPM results