You can learn something new every day, sometimes two.
I've had a very small fuel leak ever since I put my polishing system in. It was in an odd spot and I never could trace it to a specific fitting. I figured it was a valve stem. I kept a pad wedged under a hose where it appeared and this would last through the season.
I looked in the the boat the other day and, yikes, the pad was completely soaked and there was fuel in the bilge. The fact of the one change to the system, my heater supply tank, and the greater amount of fuel allowed me to trace it back to its source, a valve and Tee combination installed in one of the least accessible places in the engine space. The fuel had been running down through a joint in the wooden enclosure for the galley drawers which is one reason I was never able to trace it. The little leaks just disappeared immediately into the woodwork.
Formerly, this fitting was wet only when the polishing system was running and under almost no pressure. With the heater tank in the line there is a foot of head pressure on it full time and a gallon of fuel that can leak.
I pulled the whole thing out, one of those horrible jobs where the lines can't be completely drained. BTW go by oil spill clean up pads now. Hamilton told me that, when theirs are gone, there may not be any more and they will be very expensive. They are going to need a lot of them in the Gulf.
I put this collection of fittings together in the dead of winter. Looking at it and finding that I could take up another turn on most parts makes me think that wicked tight is not the same thing with fittings and pipe compound that have been cold soaking in a boat shed as when everything is 50 - 100 degrees warmer.
After cleaning up the nations second largest oil spill of the week, I put it all back together. I noticed that all the new hose I bought was much smaller diameter than what I bought a couple years ago. I was able to reuse one piece, the 1/4" emergency crossover line from the polishing system to the engine supply.
Damn! As soon as I turned on the polishing system, fuel began to run out the hose barb of the crossover line. It wasn't the threaded part which I had turned as tight as I could in a vice with all new compound but the hose itself. I tightened the hose clamps until the hose was about half its original OD and the flow didn't slow a bit. I drained the system back and removed the hose.
MaineSail showed up about this time. He thinks that the very thick wall fuel hose being sold at both Hamilton and West Marine a couple years ago was actually intended for machine swaging. He also suggested using the conventional looking open tooth hose clamps in with this smaller size hose. Solid clamps are such a give that I wouldn't have thought of it.
I bought new hose, much smaller OD for the same ID, and open clamps. Everything was then tight, even against the full pressure of my unregulated polishing pump.
The large head of the AWAB clamps evidently forces the hose into a "D" shape and fuel runs out the corners. The clamps are so wide that the second clamp isn't fully on the nibble and can't always force the other side in enough to make a tight connection. Watching how the narrower open tooth clamps conform to the hose, I'm convinced that they are the way to go for small fuel line sizes.
I've had a very small fuel leak ever since I put my polishing system in. It was in an odd spot and I never could trace it to a specific fitting. I figured it was a valve stem. I kept a pad wedged under a hose where it appeared and this would last through the season.
I looked in the the boat the other day and, yikes, the pad was completely soaked and there was fuel in the bilge. The fact of the one change to the system, my heater supply tank, and the greater amount of fuel allowed me to trace it back to its source, a valve and Tee combination installed in one of the least accessible places in the engine space. The fuel had been running down through a joint in the wooden enclosure for the galley drawers which is one reason I was never able to trace it. The little leaks just disappeared immediately into the woodwork.
Formerly, this fitting was wet only when the polishing system was running and under almost no pressure. With the heater tank in the line there is a foot of head pressure on it full time and a gallon of fuel that can leak.
I pulled the whole thing out, one of those horrible jobs where the lines can't be completely drained. BTW go by oil spill clean up pads now. Hamilton told me that, when theirs are gone, there may not be any more and they will be very expensive. They are going to need a lot of them in the Gulf.
I put this collection of fittings together in the dead of winter. Looking at it and finding that I could take up another turn on most parts makes me think that wicked tight is not the same thing with fittings and pipe compound that have been cold soaking in a boat shed as when everything is 50 - 100 degrees warmer.
After cleaning up the nations second largest oil spill of the week, I put it all back together. I noticed that all the new hose I bought was much smaller diameter than what I bought a couple years ago. I was able to reuse one piece, the 1/4" emergency crossover line from the polishing system to the engine supply.
Damn! As soon as I turned on the polishing system, fuel began to run out the hose barb of the crossover line. It wasn't the threaded part which I had turned as tight as I could in a vice with all new compound but the hose itself. I tightened the hose clamps until the hose was about half its original OD and the flow didn't slow a bit. I drained the system back and removed the hose.
MaineSail showed up about this time. He thinks that the very thick wall fuel hose being sold at both Hamilton and West Marine a couple years ago was actually intended for machine swaging. He also suggested using the conventional looking open tooth hose clamps in with this smaller size hose. Solid clamps are such a give that I wouldn't have thought of it.
I bought new hose, much smaller OD for the same ID, and open clamps. Everything was then tight, even against the full pressure of my unregulated polishing pump.
The large head of the AWAB clamps evidently forces the hose into a "D" shape and fuel runs out the corners. The clamps are so wide that the second clamp isn't fully on the nibble and can't always force the other side in enough to make a tight connection. Watching how the narrower open tooth clamps conform to the hose, I'm convinced that they are the way to go for small fuel line sizes.
