bob2@padowicz.com
Recruit
- Joined
- Jul 25, 2018
- Messages
- 1
I have a 1975 50HP Mercury 500 with 2 type KA carburetors. The motor was running fine, and quit when tanks switched on a 20 mile trip. Couldn't get restarted. Rebuilt the 2 carburetors and fuel pump. Motor ran about 10 minutes on a hose, quit and wouldn't restart. Water pump good, perfect compression and strong spark.
In checking carburetor butterflies I found that when the fast idle lever was moved from minimum to maximum there was ONLY ignition advance and the carburetor butterflies were still closed. It appeared that this might be correct since there are small holes in the butterflies to allow some airflow when closed? Is this correct?
Wanted to resolve this question before removing the carburetors and disassembling them again. These particular carburetors have "idle tubes" with very small passages and holes; that could possibly still be clogged.
In checking carburetor butterflies I found that when the fast idle lever was moved from minimum to maximum there was ONLY ignition advance and the carburetor butterflies were still closed. It appeared that this might be correct since there are small holes in the butterflies to allow some airflow when closed? Is this correct?
Wanted to resolve this question before removing the carburetors and disassembling them again. These particular carburetors have "idle tubes" with very small passages and holes; that could possibly still be clogged.