Mercury Classic 50 45hp wont start

[smitty28]

Motor is a 1986 45hp Mercury Classic 50. It has always ran perfect in the past and was always well maintained. It has been kept in the garage for 5 years and has not been ran in that amount of time.
I have a new gas tank with fresh mixed gas, new spark plugs, new battery but cannot get it to fire. I have good spark on all 4 cyl, nice blue spark on gapless plugs. It also seems to be getting gas to the cyl, the bulb stays hard, the carbs will drip if I over pump and the plugs seem moist from gas when i check. I did a compression test and all cyl have great compression.
When I turn it over, it turns nice and brisk but not a pop, sputter, poof, chug,...nothin!! Just turns and turns. I have also tried putting a small amout of gas in each plug hole...stil nuthin!!! I really dont think its a gummed up carb because it seems to pass fuel, but who knows.
Any suggestions??? where do I go from here? Im throwing around the idea of buying a manual or maybe just taking it to a shop....It would really be rewarding to fix this myself tho.

 

[scuba4me]

Re: Mercury Classic 50 45hp wont start

Are you sure the plug wires are on the right plugs? Are the gapless plugs the right ones for your motor? Have you tryed with the old plugs?

 

[smitty28]

Re: Mercury Classic 50 45hp wont start

Are you sure the plug wires are on the right plugs? Are the gapless plugs the right ones for your motor? Have you tryed with the old plugs?

Yes, I doubled checked the plugs are correct for this motor...the plug wires should be correct, they are going from the coils from top to bottom...top coil to top plug, etc...i wouldnt think the wires would cross and the wires are only long enough to connect to the correct plug (with a little slack)

 

[scuba4me]

Re: Mercury Classic 50 45hp wont start

The manual says if:
"Coils Fire with Spark Plugs Out but Not In:
Check for dragging starter or low battery causing slow crainking speed. Test peak voltage on the stator and trigger. Disconnect the rectifier , regulator, and retest. If the problem goes away, replace the rectifyer and/or the regulator."

Hope that helps get you in the right location of the problem. It does not say the peak voltage or what its supposd to be.

 

[smitty28]

Re: Mercury Classic 50 45hp wont start

Thanks scuba!!! Will do some testing tonight. It really does seem like the plugs are not firing when theyre in.

 

[smitty28]

Re: Mercury Classic 50 45hp wont start

Ok I did some readings with a Multimeter at the switch box:

Blue to Blue/Wht = OPEN

Red to Red/Wht = 153 ohms


Anybody know why the blues are testing open...could that be a problem?

 

[powderfinger]

Re: Mercury Classic 50 45hp wont start

When you say the carbs will drip if over pumped. How badly are they dripping? Once the carb bowls are full of gas you shouldn't be able to pump the bulb anymore. Typically from what I have seen, if fuel is coming out of the carbs while pumping the bulb then the floats are out of adjustment. It has happened to me several times.

If that was your problem then it would be flooded from priming it and you would smell gas real strong when try to crank it repeatedly.

 

[smitty28]

Re: Mercury Classic 50 45hp wont start

When you say the carbs will drip if over pumped. How badly are they dripping? Once the carb bowls are full of gas you shouldn't be able to pump the bulb anymore. Typically from what I have seen, if fuel is coming out of the carbs while pumping the bulb then the floats are out of adjustment. It has happened to me several times.

If that was your problem then it would be flooded from priming it and you would smell gas real strong when try to crank it repeatedly.

I guess my point was that it seems to be getting gas just fine and fuel delivery doesnt seem to be the prob...Anyway's, Im still conserned that the blue to blue/wt wires from the stator is testing open...does anyone have any input on this???

 

[smitty28]

Re: Mercury Classic 50 45hp wont start

I guess my point was that it seems to be getting gas just fine and fuel delivery doesnt seem to be the prob...Anyway's, Im still conserned that the blue to blue/wt wires from the stator is testing open...does anyone have any input on this???

It ended up being a bad stator, I replaced, now shes runnin...thanks for all your help!!