Michael, Thank you very much for the reply. I hope the rest of the list will indulge in an A4 discussion. Yes, there's a mechanical fuel pump. The stainless sedimenter bowl was "squeaky clean", no crud. The transparent (automotive) gas filter just in front of the sedimenter bowl was/is also "squeaky clean". There is also a canister filter adjacent to the gas tank. I have not had that apart. I've been "pretty good" about using ethanol-free gas and the gas tank has been full throughout the winter. The failure to (re)start coincides with the exhaust riser failure which was noticed at the dock while running the engine after an oil change. Any elaboration of alternate theories is appreciated in advance. Bob M Ox 33-1 Jax, FL
On Fri, Mar 7, 2014 at 7:57 PM, Michael Brown <m...@tkg.ca> wrote: > Dirty carb? > > Water backing up through the exhaust, through the motor, then through the > intake system into the carb is pretty unlikely. I mention this since if > the actual > source of the contamination is something else you could have the problem > again. > > Do you have a mechanical fuel pump? If so there is a metal cup on the stern > side of it, held in by a bail. Place a coffee filter in a clean tin can, > remove the > cup and dump the gas out into the can. Check the filter and the bottom of > the cup for debris. A few A4s I have checked were running "fine", but at > least half of the cup was full of sediment. > > The mechanical fuel pump has a level, looks like a coat hanger bent around > the pump, that is a primer to get gas back into the carb after the lines > have > been drained without cranking the engine. > > My opinion, not shared by many, is that the inline fuel filters of the sort > sold for cars do not filter well. The opinion is based on wiping the cup > out > with a clean cloth, then doing the same a year later. The A4 is a very > small > engine, 17 - 30 HP compared to 150 and up for a car. The tiny jet, > infrequent > use and low intake vacuum on the A4 make it sensitive to the stuff that > would pass through a car. > > The bulkhead mounted filter / water separators that have a oil filter sized > canister are good to remove particulate down to 10 microns. I like the type > that have a heavy shell, and the filter is inside. Some come with a drain > at > the bottom, makes it easy to check for water. Get the drain plug that has > a slot / hole cut in it so the plug does not have to be removed to drain > the filter. > > A lot of work for a couple of cans a gas a year ... > > > Michael Brown > Windburn > C&C 30-1 > > > Date: Fri, 7 Mar 2014 18:40:33 -0500 > From: "bobmor99 ." <bobmo...@gmail.com> > To: kenhea...@gmail.com, cnc-list@cnc-list.com > Subject: Re: Stus-List Exhaust Riser Replacement > Message-ID: > <CAM7ccYKJ5W5XGtqdwo4DDE=9je2rjdpofpdxq87ygfbiu8g...@mail.gmail.com> > Content-Type: text/plain; charset="iso-8859-1" > > Brief update: > Mechanic friend removed the carb and cleaned out lots of gaboo. Started > right up after that. > Water and crud must have somehow backed up through the exhaust manifold > into the carb while the exhaust riser was failing and there wasn't enough > pressure to keep everything (exhaust and cooling water) moving aft > Life is good. Long live the A4 > > Bob M > Ox 33-1 > Jax, FL > > > _______________________________________________ > This List is provided by the C&C Photo Album > http://www.cncphotoalbum.com > CnC-List@cnc-list.com > >
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