fouling plugs after decarb

[cdoliver]

hey everyone, I just did a decarb on my 83' 140 rude(per the decarb instructions found on this site). It was running great before the decarb. Now it won't run 5 mins before it fouls the plugs and stops running @wot . It just bogs down. I can pull the plugs and clean them and it will run another 2-3 mins and then same issue. Do I just keep doing this, Or do I need to do another seafoam application? Thanks

 

[OptsyEagle]

Re: fouling plugs after decarb

If I were you I would simply put in brand new plugs, instead of just cleaning the old ones. It's not easy to properly clean a fouled plug. I would also ensure that your rich/lean adjust is adjusted to the optimum level and that your T-stat is operational.

 

[cdoliver]

Re: fouling plugs after decarb

I put brand new plugs in after the first ones fouled. I knew they were going to probably foul so I had some ready. After 5 mins the new ones were fouled. So my only option at the time was to clean them. These are the plugs that are flat on the bottom. My carbs have been rebuilt and I don't believe there is a rich/lean adjustment. The Tstats are working. Should I just do another decarb or two?

Thank you.

 

[tashasdaddy]

Re: fouling plugs after decarb

try some Champion, QL77JC4's gapped at .030. the flat ones are known to foul. it sounds like the float needles are not closing, flooding the cylinders.

 

[cdoliver]

Re: fouling plugs after decarb

I didn't even consider that becuase I thought the flat ones were used for some clearance reason... I'll try that before I pull the carbs off again. I was running great before the decarb. Thanks Tash.

 

[ezeke]

Re: fouling plugs after decarb

The QL77JC4 is recommended for sustained slow speed operation of your engine.

The decarb process usually takes three complete treatments on a badly fouled engine. You need to run the released carbon out between each treatment. I'm not happy until I see clean metal on the top of the pistons and I find that when that happens the spark plugs are usually clean as well.

In Captain Dunkelberger's instructions He says: "...
Run the engine 15 mins in the dock or just cruising around under 2500. Then shut it down and let it sit for 15 mins. Restart the engine, the smoke you see is the carbon burning off. Do the whole thing again and let her sit again for 15 mins. If she smokes after the second time do it again, but I've never seen one still smoke after three doses. The gallon mix should be enough to do this 3 times. You don't need any wide open throttle; you don't need to change the plugs. If it's cleaning the combustion chambers it's also cleaning the plugs...." see: http://outdoorsbest.zeroforum.com/zerothread?cmd=print&id=2589

 

[cdoliver]

Re: fouling plugs after decarb

well... I didn't do the 15 mins of sitting... I just ran the whole gallon out at once. Maybe that's my problem. I'll check back when I do it properly.

 

[tashasdaddy]

Re: fouling plugs after decarb

i do this which is very similar.

Decarb, take a can of seafoam put 3/4 of it in the gas tank, with only 1 gallon of premixed gas. put the rest in a spray bottle. start the engine, and let it come up to temperature. then remove plugs, and them some real good shot of seafoam into the cylinders, replace plugs, let sit 15 minutes. restart, and spray the rest of the seafoam into the carbs, so the the motor almost stalls, wait and repeat until the seafoam is gone.then take for a wide open spin. then put in new plugs, ad premixed gas to the tank, and take it for a wide open throttle spin. it is going to smoke like a house on fire, during this process.

afterwards compression.recheck