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I am wet fouling plugs, and feel like I am chasing my tail. So here is what I have.
The motor is a SBC, flat top pistons with 2 reliefs. Zero deck with World Product Sportsman II heads, a rough estimate of 9.5 to 1. Carb is a Holley 3310, with no secondary jet plate, running 69's in the primary. MSD ignition with AR133 plugs, running on 93 octane pump gas. Total advance is 34*.
This is a new short block from last year. The top end of the motor is the same as I had last year. The newer motor has a slightly more aggressive cam. During break in it seemed to run fine, I thought I could hear an occasional misfire. After changing the oil and filter, I pulled the plugs.
Not much carbon, the color looked ok. But the plug was wet, the liquid looked like you dunked it in Pepsi. It did not appear to be oil, because it stunk like fuel and the motor does not smoke at all. Although the plugs were a little sticky. Also the entire plug wasn't soaked, just sorted of "misted" on there.
My first thought was plugs were to cold. I stepped up to AR134's but the misfiring appeared worse. So I went back to a new set of AR133's and stepped the jets down from 76's to 74's. Ran it another 20 minutes, did a good shut down and pulled the plugs to check them. Same thing; wet and sticky. I kept repeating this process of stepping down jet sizes until I got to the 69's that are in there now. And again no change. I know the 69's are too lean but I was hoping to get to a point where I would see a change on the plug.
Here are some things I do know to be good. Header temps range from 550 to 750 depending on what cylinders they are. Ignition system gives me a nice sharp snapping blue spark. The power valve is not blown; I turned the idle screws in and it stalled. My idle mixture screws are set at 1 1/4 turns, this gives me the highest vacuum reading at 15 psi. It seems a little on the low side so I think I might be a smidge too advanced with the timing.
Am I missing something that is probably right in front of my nose? Is it possible that the rings are not seated, have absolutely no smoke at any time, and still oil foul a plug? Also running it in the shop at 3,000 rpm I can not get the water temp over 145 degrees. Is it possible the engine is too cold? Working on the car again tonight, and I think it is just a combination of fuel mixture, timing, and engine temp I have to get sorted out. But I will be picking up a leak down tester Saturday morning if I can't get it ironed out tonight. To rule out rings not broke in, and valves not seating. I really don't think it's internal because I have no smoke, there is no popping in the carb, and the header temps are not high. So I am not leaking any combustion out an unseated valve. And the motor does sound healthy, except for the loading up and fouling plugs problem haha.
The motor is a SBC, flat top pistons with 2 reliefs. Zero deck with World Product Sportsman II heads, a rough estimate of 9.5 to 1. Carb is a Holley 3310, with no secondary jet plate, running 69's in the primary. MSD ignition with AR133 plugs, running on 93 octane pump gas. Total advance is 34*.
This is a new short block from last year. The top end of the motor is the same as I had last year. The newer motor has a slightly more aggressive cam. During break in it seemed to run fine, I thought I could hear an occasional misfire. After changing the oil and filter, I pulled the plugs.
Not much carbon, the color looked ok. But the plug was wet, the liquid looked like you dunked it in Pepsi. It did not appear to be oil, because it stunk like fuel and the motor does not smoke at all. Although the plugs were a little sticky. Also the entire plug wasn't soaked, just sorted of "misted" on there.
My first thought was plugs were to cold. I stepped up to AR134's but the misfiring appeared worse. So I went back to a new set of AR133's and stepped the jets down from 76's to 74's. Ran it another 20 minutes, did a good shut down and pulled the plugs to check them. Same thing; wet and sticky. I kept repeating this process of stepping down jet sizes until I got to the 69's that are in there now. And again no change. I know the 69's are too lean but I was hoping to get to a point where I would see a change on the plug.
Here are some things I do know to be good. Header temps range from 550 to 750 depending on what cylinders they are. Ignition system gives me a nice sharp snapping blue spark. The power valve is not blown; I turned the idle screws in and it stalled. My idle mixture screws are set at 1 1/4 turns, this gives me the highest vacuum reading at 15 psi. It seems a little on the low side so I think I might be a smidge too advanced with the timing.
Am I missing something that is probably right in front of my nose? Is it possible that the rings are not seated, have absolutely no smoke at any time, and still oil foul a plug? Also running it in the shop at 3,000 rpm I can not get the water temp over 145 degrees. Is it possible the engine is too cold? Working on the car again tonight, and I think it is just a combination of fuel mixture, timing, and engine temp I have to get sorted out. But I will be picking up a leak down tester Saturday morning if I can't get it ironed out tonight. To rule out rings not broke in, and valves not seating. I really don't think it's internal because I have no smoke, there is no popping in the carb, and the header temps are not high. So I am not leaking any combustion out an unseated valve. And the motor does sound healthy, except for the loading up and fouling plugs problem haha.
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