Sudden decrease in RPMs at cruise

Quote:

---

Originally Posted by Barnacle Bill

Never heard of that before. That is very strange.

---

It's strange that I get a reading of zero or strange that the two out of six are like that? Sorry for ignorance.

If you have 3 carburetors I’m afraid that it may have been the bottom carburetor has stopped fueling and the rings at minimum are gone. It sounds more like a lean seize to me now. Last engine I had that did that was a Mercury. I hope I’m wrong.

Quote:

---

Originally Posted by cattoon

If you have 3 carburetors I’m afraid that it may have been the bottom carburetor has stopped fueling and the rings at minimum are gone. It sounds more like a lean seize to me now. Last engine I had that did that was a Mercury. I hope I’m wrong.

---

Yes, three carburetors.

What did spark plugs look like in those cylinders?

Quote:

---

Originally Posted by Mbsbeek

What did spark plugs look like in those cylinders?

---

I didn't notice anything different from the rest but I don't recall scrutinizing them closely like I wish I would have. Gapless plugs.