50hp mercury (another Question?)

[b75nweav]

Thanks for the help with the throttle cables. Got them working great. Have a new problem though. Boat has been running great for the past 4 weekends and yesterday I took my wife and daughter out for a boat ride and the damn thing ran like crap. It idled fine but as soon as you gave it gas it was very sluggish. Did the same thing today with my brother with me. I have replaced stator, switchbox, rectifier all cyl have about 110lbs compression, Good fire from all plugs new throttle and shift cables. The only thing I can see that is wrong is the top carb throttle is open about a 1/16 in neutral, I believe its supposed to be closed. I took carbs off a while back to replace diaphram and broke the plastic coupler that connects to both carbs. I adjusted as good as I could but could not get the top throttle to close all the way, the bottom one is closed though. Like I said its has ran good with just me in the boat for a couple weeks now and I know the carb was that way when it was running fine. Checked the trigger using service manual and checked out ok. Any ideas. trouble shooting this motor is a pain in the &*(%%. OH YEA! its a 87 mercury 4cyl 50hp.

 

[Laddies]

Re: 50hp mercury (another Question?)

Yes the carb should be closed at idle, it sound like the engine has some junk that came loose in the carbs take the off and clean them then do a synchronization on it

 

[jebeebe]

Re: 50hp mercury (another Question?)

Hi,
I broke the coupler on my 60 3 cyl and had to replace it. I held the butterflys shut and tightened the screw on the coupler and they stayed in synk. Don't know if that helps or not but that's my two cents.
Jerry

 

[b75nweav]

Re: 50hp mercury (another Question?)

I tried that too but when I tightened the screw they both opened up. Had to really turn the top one to close it all the way and when I tightened the screw the bottom one opened up just like the top one. Oh yea I was reading these post and this guy had a 40 hp had almost the same problem but he menitioned having water squirting out just above the foot just under the couling on the boat side of the motor. I have the same thing happening on mine. was doing it the other day when boat was running fine though, so I thought nothing of it. Boat pee's great though, probably time for water pump and seal replacement . mabye that little piece of infor will help someone help me............thanks

 

[Laddies]

Re: 50hp mercury (another Question?)

You will never make it run turning this and that all that does is compound your problem. Use a manual and do the job right, you and all the neighbors twisting things won't help. Start by cleaning the carbs, you wouldn't try to fix your car with those methods I hope

 

[b75nweav]

Re: 50hp mercury (another Question?)

How about the water coming out the mid section. Right under the cowling.front side of motor 2 bars or bolts go into the midsection from the motor mount, they look like they have a gasket around them. It doesnt come out with ears on only in the water. Think that might have something to do with is.

 

[b75nweav]

Re: 50hp mercury (another Question?)

How do I check to see if its my head gasket? My manual tells me how to dissassemble and reassemble the entire powerhead but does not disscuss troubleshooting something like that. What is that hole below the cowling anyway, has 2 pins or bars going into it with a plastic gasket around them. Should water becoming out of it, is that normal. 87 mercury 50hp 4cyl. .........come on laddies, help me out.

 

[Plainsman]

Re: 50hp mercury (another Question?)

Seems to me that if you have water coming out it would be the waterjacket leaking. That is how the motor is cooled. If you remove the cowling you should be able to see where the water is coming from.

 

[Laddies]

Re: 50hp mercury (another Question?)

The 2 bolts that are leaking are caused because the upper motor mounts are shot to repair them you will have to remove the powerhead they usually won't effect running but somethings will bother the idle because the engines suck exhaust