Today I deceided to pull the carbs to rebuild. When I pulled them apart, they were as clean as new. The float were set at 7.5mm.
The plugs look like the day I put them in.
If your plugs did not show any signs of a rich mixture, I would not have pulled the carb.
Many folks have the opposite problem on these 1500s. The dreaded "hesitation".
I would much rather have this damn carb run a little richer on this 1500. The notoriou hesitation is a very very bad nuisance.
Re-adjusting the floats or changing the jets would lean the F/A mixture. But, if you go too far, you would then have the lean dead spot hesitation. But, you said your plugs were clean.
I commend you for pulling the carbs. Many cop out and take the easy way out. For lean carbs, fuel additives such as Seafoam is used to hopefully clear the jets. tBut, there is much truth to this. I am not a fan of fuel additives, but working on these carb is a tremendous task. But, in your case, you are running rich.
Since you have already tackled Humpty Dumpty, I am sure you will try a lean/tweek the carb a little while you are there. If you do succeed, great. If not, try and try again.Many want to do itright the first time... for many, the first time is Seafoam for lean F/A mixtures.
Rebuilding the carb and going for the jugular is great, and hopefully it is done right the first and only time. What a pain. I hate these carbs.
Lastly, there was a service bulletin on these carbs 88 and maybe 89 carbs. Changes carb jets.