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On my last trip the A-4 ran like a champ for the first few weeks. Instant start, steady PRM and consistent 8 hr days of running. Then on a day with following seas I noticed a slight RPM variation. Hard to pick up on the tach but I could hear/sense it. I, ever the optimist or maybe just lazy, blamed it on the conditions loading and unloading the prop. Wrong. The next day I had the same thing on flat water. I decided to adjust the main jet, I have the early model carb. I no more than touched the packing nut and she ran smooth as could be?????. Every few days for the next week or so the problem would return. After a few more attempts at adjusting in place I removed the assembly and cleaned it, no sign of gunk, and shot carb cleaner thru the main jet. This did the trick for about a week as I worked my way back down the St Johns River thru Jax and turned N for the trip back to NC. A day or two later as I approached St Andrew Sound she started dropping the RPM again but this time I could see it on the tach. I was heading down the Cumberland River with a helpful SW 15-20 but fighting the flood current. Not the best conditions for St Andrew. So I am running thru my options when the A-4 stumbles/catches/stumbles and dies. I swing over to some shallower water under sail and drop the hook. Very bouncy but I could see that my inline filter just before the carb was dry. Must be getting air in some where or the pump has died or the OPSS is shot?? I tightened all the hose clamps, bypassed the OPSS, and she primed just fine. Fired up and off I go. The next hr was a tense, rough battle thru the most confused seas I have ever been in. To top it all off the CG had removed the R-32 marker since the last time I was thru here two weeks before. Being a couple hundred miles S and not really listening I had missed the info on the NTM. My mistake. Thank goodness for my chartplotter and the fact that this was my forth time thru in as many weeks. I made the turn and flew up to the anchorage behind Jekyll Island. This was the start of the most frustrating week I have ever spent on a boat. Everyday she would shut down with little warning. The inline filter would be empty but if I "messed" with things and jumped the OPSS she would refill. I thought it was my carb when I made the mistake of removing the plug in the bottom of the throat, remember earlys do not have the external scavenge tube, instead of the bowl to check for gas. No gas! Well dahh. This led to a "needless" carb cleaning as I sat at anchor. Switched to my spare fuel pump no change. I thought it might have been my petcock clogging because I spun it 180 deg from open and a blob of crud showed up in my inline filter. After the petcock deal I made it thru Elliot Cut, Wappoo Cr, Charleston Harbor and as I started to pass thru Ben Sawyer bridge she shut down. I had the jib ready and raised it and sailed thru. At this point I had been fighting for four days and 200 miles. I did some more cleaning, tightening etc that night but the next day near Mc Clellanville SC she shut down. I decided to strip the fuel system down to the bare bones. Hose in main tank to eliminate the pickup tube and possible crack/air leak, bypass petcock and water separater filter and noticed that it sounded empty but was in fact half full, jump OPSS. SHE RUNS. After two days of no shut downs I have to start adding things back or I will never know what the problem was. I added back the petcock filter assembly and the next day after running fine for hrs she shut down. I must give the Marian Claire credit because she did this just before I entered the area known as the Rockpile. A rock lined section of the ICW and no place to have problems. I dropped the hook removed the petcock/filter and away we go. It has now been a week of constant tension and long days due to stops and late nights for repairs. I am exhausted. I know I could have stopped but what could I learn from sitting. The constant SW wind also played into it. Over the next few days I slowly, one at a time replaced/returned to normal the fuel system. Except for the petcock/filter. She ran great and I made it back to Matthews Point. I set up the boat for slip life and made sure I disconnected and plugged the fuel line at the top of the tank. With no petcock I did not want to risk a flooded carb/boat.
I brought the P/F assembly home and pressure tested it for leaks. I made the mistake of disassembling/cleaning and greasing the petcock before I pressure tested. No leaks.
My theory is that given that the P/F was the highest point in my fuel system any air leak may have allowed air to build up in the filter. This could take hours and when enough air built up the Facet pump would have to pump a "large" amount of air thru the carb to re-prime. This would cause the shut down. I plan to reinstall the P/F at a point lower than the carb. This way if there is a small air leak the air will pass thru the filter and not build up.
Advice is welcome. Dan S/V Marian Claire
Edit: P/F stands for petcock/filter
I brought the P/F assembly home and pressure tested it for leaks. I made the mistake of disassembling/cleaning and greasing the petcock before I pressure tested. No leaks.
My theory is that given that the P/F was the highest point in my fuel system any air leak may have allowed air to build up in the filter. This could take hours and when enough air built up the Facet pump would have to pump a "large" amount of air thru the carb to re-prime. This would cause the shut down. I plan to reinstall the P/F at a point lower than the carb. This way if there is a small air leak the air will pass thru the filter and not build up.
Advice is welcome. Dan S/V Marian Claire
Edit: P/F stands for petcock/filter
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