My son posted some time ago about our 48 8N, 139472, ft mnt, 12V with alt. It had been missing most of the summer and had low power. All cyl had good spark but still ran on 2 or 3 cys. Now that mowing season if over we decided to pull the head and see what was going on. The breaker plate had been replaced, new sparkies, good fuel flow. Started every time, no smoke. Before taking the hood off, I decided to check out the manifold as it had oil in the 1 and 2 cy intake port. Placed manifold on ground and used garden hose to fill the exhaust side. Water came out in the 1 - 2 intake port. So we had been fighting this all year, but replaced manifold, tbl fixed! Runs like a new one. I also checked the new manifold before installing.The old manifold had been on about a year and half.