A4 stuff
- Thread starter steven
- Start date
DynamicDave
Member I
I know these arn't cheap but....
After rebuilding my old carb (that had stuck floats after a long winter) and increasing the run time to an hour or more, I still had poor idle and the sudden engine stoppage that was unexplained. I sprung for a new carb,as well as new racor and finishing filters, confirmed proper output pressure on the electronic fuel pump and changed ALL fuel lines and double clamped the darn things to reduce unwanted air intake. Don't forget to clean the intake screen too. Fresh fuell w/ additives to retard water and growth, and Yes, I do use a bit of MarvelMystery oil in the tank. My dad says to save the bucks and add a liter of kerosene to each 20 gal tank, but I prefer to spend $8 for the MM oil. My Bad.
Do the whole thing, all at once, and you may just find you can trust your A4 again! Plus spend more time sailing/motoring, and less time worrying what you need to do next to the old heap of iron.
I love my A4. It's the same kind of motor I've been working on since the 60's, it's basic, and if you put quality parts on it, the rewards are bountiful.
Don't fix it till you're broke, but fix it right the first time!
After rebuilding my old carb (that had stuck floats after a long winter) and increasing the run time to an hour or more, I still had poor idle and the sudden engine stoppage that was unexplained. I sprung for a new carb,as well as new racor and finishing filters, confirmed proper output pressure on the electronic fuel pump and changed ALL fuel lines and double clamped the darn things to reduce unwanted air intake. Don't forget to clean the intake screen too. Fresh fuell w/ additives to retard water and growth, and Yes, I do use a bit of MarvelMystery oil in the tank. My dad says to save the bucks and add a liter of kerosene to each 20 gal tank, but I prefer to spend $8 for the MM oil. My Bad.
Do the whole thing, all at once, and you may just find you can trust your A4 again! Plus spend more time sailing/motoring, and less time worrying what you need to do next to the old heap of iron.
I love my A4. It's the same kind of motor I've been working on since the 60's, it's basic, and if you put quality parts on it, the rewards are bountiful.
Don't fix it till you're broke, but fix it right the first time!
steven
Sustaining Member
saving an A4 - update
well I was all set to re-power. But compression was good in all cylinders, so on the theory that it was the fuel system (thanks to advice of David and others on this Forum) made a last ditch attempt to save the engine.
So . . . rebuilt carb, new fuel filter, add second inline fuel filter, replaced all fuel lines, replaced mechanical fuel pump with rebuilt, hotter plugs, new flame arrestor (the old one was cracked), replaced a few other minor parts while in progress, and of course tune up and new fuel. Sibley Marine in Shadyside, MD did the work (someone on this forum recommended him but I can't recall who and cannot find the thread - but thanks).
Purring again. (can get to 2k RPM in fwd tied to the dock - never was able to do that before)
In progress arranging for tank fuel tank to be flushed ("polished").
There was green gunk in the fuel lines and carb. Biologic? copper oxidation? oil in fuel? Don't know what - but it's clean now.
Much thanks to all for advice and moral support.
PS - temp gauge appears to be a casualty. Any recommendations on replacement?
--Steve
well I was all set to re-power. But compression was good in all cylinders, so on the theory that it was the fuel system (thanks to advice of David and others on this Forum) made a last ditch attempt to save the engine.
So . . . rebuilt carb, new fuel filter, add second inline fuel filter, replaced all fuel lines, replaced mechanical fuel pump with rebuilt, hotter plugs, new flame arrestor (the old one was cracked), replaced a few other minor parts while in progress, and of course tune up and new fuel. Sibley Marine in Shadyside, MD did the work (someone on this forum recommended him but I can't recall who and cannot find the thread - but thanks).
Purring again. (can get to 2k RPM in fwd tied to the dock - never was able to do that before)
In progress arranging for tank fuel tank to be flushed ("polished").
There was green gunk in the fuel lines and carb. Biologic? copper oxidation? oil in fuel? Don't know what - but it's clean now.
Much thanks to all for advice and moral support.
PS - temp gauge appears to be a casualty. Any recommendations on replacement?
--Steve
Really good to hear your follow up - the A4 is a good engine and worth saving, and it sounds like with all the goo you found you hit it on the head. Sitting too long could be a big part of the issue.
Regarding gauges, I've installed a handful of Teleflex gauges with good results. I would have told you I had used their "value line", but I'm not seeing that series specifically at Defender right now, but, they have a variety of gauges right around $25, and the last time I checked, they were making them here in the U.S.
http://search.defender.com/?Action=...49Mn4&SI=7e08b3cb-be78-437a-bfee-fe64c6be89b4
Regarding gauges, I've installed a handful of Teleflex gauges with good results. I would have told you I had used their "value line", but I'm not seeing that series specifically at Defender right now, but, they have a variety of gauges right around $25, and the last time I checked, they were making them here in the U.S.
http://search.defender.com/?Action=...49Mn4&SI=7e08b3cb-be78-437a-bfee-fe64c6be89b4
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DynamicDave
Member I
Fuel petrie dish...
Having just replaced my racor filter/water seperator on my trusty A4 , I found the typical rancid goo in the water drop chamber, coating the lower dashpot, that I've found in previous diesel systems.I too, thought that there was little in the way of flora in a typical GAS fuel system! Wrong again. Even with monthly filter/water purging there was still a tangible amount of growing ooze in the system. Additives have reduced the growth from last year a bit! I replace both water seperator and finishing filters yearly and use only filtered premium leaded fuel, with a topped off tank for winter storage. Yes I'll add a pint of Miracle Oil and fuel stabilizer to my 20gal tank too.
Having just replaced my racor filter/water seperator on my trusty A4 , I found the typical rancid goo in the water drop chamber, coating the lower dashpot, that I've found in previous diesel systems.I too, thought that there was little in the way of flora in a typical GAS fuel system! Wrong again. Even with monthly filter/water purging there was still a tangible amount of growing ooze in the system. Additives have reduced the growth from last year a bit! I replace both water seperator and finishing filters yearly and use only filtered premium leaded fuel, with a topped off tank for winter storage. Yes I'll add a pint of Miracle Oil and fuel stabilizer to my 20gal tank too.
steven
Sustaining Member
Confirmed that flora was at least part of the goo. Had my fuel tank flushed - procedure is to pump it dry and then recirculate gas through the tank and external filters for awhile. Fuel was brown-green almost opaque for about 30min until it finally cleared up. The folks who did the flush said it was likely old fuel + water separation + biologic stuff. Also have replaced the o-rings at the deck fill so water can't get in there (they recommended replacing every year). The fill is on the cockpit floor - doesn't seem like the best place for it. I normally close the cockpit drains when I'm away form the boat for awhile and a little water can build up on the cockpit floor - will have to re-think that.
DynamicDave
Member I
Never say never, but....
Never close your cockpit drains, never. oh well... d
Never close your cockpit drains, never. oh well... d