Should I rebuild Mercarb myself?

[tuanp]

I have a Merc MCM170 that I would not start even with spark and gas in cylinders. The problem is described in this thread. The replies there suggest I may need to rebuild the carb 'cause it's flooding my cylinders. Looks like the mixture is also too rich as the plugs are all blackened.<br /><br />The carb I have is a 2 bbl Mercarb. Is this something I can rebuild myself? So far I've replaced the waterpump and fixed up the tilt/trim pump motor, and I'm able to understand the Clymer manual's procedures. I was told that I shouldn't do this myself because I can't get the carburetor cleaner that the shops use to clean out the gum and varnish. Is this true? Should I attempt it myself and save some much needed $$? Thanks.<br /><br />tuan

 

[rattana]

Re: Should I rebuild Mercarb myself?

TP<br />Upon reading your previous post, I noticed that you said that the voltage at the coil was 11.7 with the key on, that seems a little high, and could be causing your problem. There should be a ballast resistor or resistive wire to drop the voltage lower in the run position. Before rebuilding your carb, I would do a quick check of the primary ignition circuit.<br />Remove the distributor cap and turn the crankshaft until the points are closed. Turn the key on and open and close the points with a small screwdriver or anything non metallic <br />Hold the high tension coil wire about 1/4" from a good ground. If you see a good spark jump from the wire to ground then the coil checks out fine. Double check this procedure when the engine starts acting up. The coil could be breaking down once it is warmed up a little. The coil doesn't like full voltage all the time.

 

[tuanp]

Re: Should I rebuild Mercarb myself?

Thanks for the suggestion. I will check the coil as soon as I can per your procedure.<br /><br />tuan