Hey Rick,These are 4 sets, each looks to be 4 pictures together of each plug.
Just for clarity, these are all after the motor ran rough for as long as it would run and then died while in a mid-throttle setting?
And you don't hve comparison photos of the plugs with the motor running decently at higher setting and then turned off?
These plugs look like at times the motor is running a teensy bit rich, evidenced by the soot on the housing. And at the time the motor quit it appears it might have been lean, the center electrode and insulator is completely free of soot and deposits and the ground electrode is shedding any deposits. It is positively not running rich at the time it died.
Ayuh,.... Those plugs were seein' no gas, a lean condition,....
Goldie,
First place is float level. Doesn't matter if it is brand new OEM carburetor - which is what we are talking here.
Next, since you're already in there, run al the ports with spray cleaner to make sure they are clear.
Double check you don't have an intake leak. I'm not totally sure if it is possible or likely, but since the intake and exhaust share the same manifold, a leak could be an internal crack if it isn't an external gasket. If you had an intake leak it would most effect throttle soon after opening. Idle can be adjusted a bit richer but low throttle settings are not easily adjustable and can be overwhelmed by a relatively small leak, causing lean condition.
Any idea how many milimetters at a time should adjust the float up? I know I want more gas in the bowl...
i was going to wait on the oil pan gasket, but if i pull the motor i can just do it all at the same time...[/SIZE]
First thing is check to see if it is correct. I've never made one higher than specifications called for. I would expect problems doing that.
I don't know how to check for an internally cracked manifold without removing it. With it removed you can fill the intake side with acetone and see if any leaks into the exhaust side. Need a set of gaskets before trying that.
its either way lean or you have water entering the combustion chambers
water in the block would also give you clattering.
Goldie,
I have to believe you gotta have an intake leak. I watched the video again, the plugs are running lean enough that any deposits are being blasted right off the electrodes when you run down to that 1000 RPM range. I'd still love to see one of the plugs after running up on plane at 2k RPM. See if it shows lean up there too.
The way the carb works: when you throttle up and start accelerating, the carb is just starting to transistion out of low range ports onto the main jets right when it begins sputtering. When you jump on the throttle to blast past that, first the accelerator pumps dumps raw fuel and then the power valve is dumping fuel along with main jets. If this was a carburetor that was not application specific and we were calibrating it, we'd up main jet size right now and see where that got us.
BUT - this is an application specific carburetor. It is jetted and calibrated like every other Mercarb made for the 3.0L. Which leads me full circle back to an intake leak somewhere. @AllDodge, can you check me on my thinking please.
Hey Rick, I want to show You the plugs on plane but not sure how to stop the motor while on plane. Is it as simple as turning off the key while on plane?
Thanks rick, friday morning ill check the carb float to make sure its to spec, then saturday ill take the boat out to test, will report backYes. Run for a ways, 5 minutes, then turn the switch off. The prop and the water will kill the motor faster than you will believe. Poof, off. Pull a plug.
Rick
Is it as simple as turning off the key while on plane?