850 mercury not idling and i got shocked.. HELP ME

college_guy

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Joined
Oct 28, 2009
Messages
25
hi, ive been stuck at this problem for a while. i need some help... I can start my motor up with the trottle up about half way but when i put it in idle (neutral) it dies about 10-30 secs after. sometimes it dies right away when i put it in idle. I did do a float change and a needle change in the crab but that did not make a difference. i did not put in any additives (stabil) during the winter time. I am from Wisc. Do yo think that could be my problem. When i did open up the carb float housing there was not alot of gas in there, is that suppose to be normal and when i pump gas into the motor it leaks out from the carb opening. I have not checked the fuel pump yet though i did check the hoses leading up to the pump and a good amount of gas came out. And is the boats rpm gauage suppose to be near the 1000 rpm mark even when the motor is not running. Another thing is i was shocked when i touched the metal case part where the sparkplugs go into. i did not touch the sparkplug, it is where the water hose comes out of and into the pee hole. Is this normal or is there a wire that is not grounded right? so many qestions with little time b4 the season opener...
 

Chris1956

Supreme Mariner
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Mar 25, 2004
Messages
27,036
Re: 850 mercury not idling and i got shocked.. HELP ME

It sounds like you have at least two problems. Neither of them have to do with your home state ha ha.

Post the year of the motor or it's serial number.

It sounds lik you carb float height is incorrect. This is why the gas pours out. It needs to be adjusted.

I would also check the spark plug wires for cracks or other damage. That is probably why you are getting shocks. Also, there should be ground wires from the block to the lower cowling. See that these are in place.
 

college_guy

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Joined
Oct 28, 2009
Messages
25
Re: 850 mercury not idling and i got shocked.. HELP ME

ok thanks ill check it out. its a 73 850 mercury i believe. where would the ground wire be on the motor block? i guess i should of checked the float.. i thought that the float height spring level would be measured already...i guess i was wrong.. and when i llok at the spark plugs the top one seems to have more burnage than the others. when i looked at one of the wires it had some rust in there not alot but would that make a difference? ill try it later and see if it makes a difference season opener starts tomorrow... thanks
 

Wingedwheel

Lieutenant Junior Grade
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Jun 16, 2009
Messages
1,071
Re: 850 mercury not idling and i got shocked.. HELP ME

I have the same motor and when I got it one of the floats was slightly swollen which caused it to stick, which caused the problem you describe. A new set took care of the problem and I think they were only about $11 ea.
 

Chris1956

Supreme Mariner
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Mar 25, 2004
Messages
27,036
Re: 850 mercury not idling and i got shocked.. HELP ME

That 1973 motor will have a distributor ignition. Check the plug wires for arcing to ground. If you find it, replace them. They unscrew from the distributor cap. I think you can get them at oldmercs.com. The distributor rotor is non-removeable. Be careful not to break it.
 

college_guy

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Joined
Oct 28, 2009
Messages
25
Re: 850 mercury not idling and i got shocked.. HELP ME

i checked it out last night and this is my findings. I found that there were alot of crap in my lower carb float unit. I also found out that the lower carb float spring was not in that good of a shape.. i will replace both and let you guys know thanks. I checked the plug wires and they seem to be new i dont know what the arch to ground is so could you be intel me more about that. thanks let me know whatelse i could do while i have the carbs removed. Also some of the wirings are starting to crumble. wires that come from the distributor to the back of the front cover plate. also wires that are attached to that cover plate it might be the switchbow, it has about 6-8 wires attached to it. Some wires crumble when i play with them. i know it might affect but what would be affected by it?
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,036
Re: 850 mercury not idling and i got shocked.. HELP ME

OK, Clean up the carbs and install new floats, needles and seats if necessary. Replace the engine wiring harness.

Arcing is when the spark escapes from the plug wire and jumps to the engine block. You usually can hear it snapping.
 
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