Help! All sorts problems came up

[orcaspirit]

First of all I been through 2 A4 in my boat over a long time period and able to fix pretty much anything A4. Including a head gasket and valve job myself. But I'm trying to coax my engine long until the as my marine mechanic has found a suitable diesel that will work. However I was getting some crappy/water in fuel (which did happened) and not running right. So I pulled the fuel system and pulled the carb to blow it out and clean all filters bowls etc. Not changing any of the settings. It san okay for a bit but not completely happy. Then running it in anger it was getting worse & worse. A lot of blow by with unspent fuel and exhaust/soot. Not proper power because of it. I get 4 knots maybe but it should be doing 6. Very recently I but in a new fuel filter, points, condenser, coil and drained the carb (again!) but still no go. Even tried some Seafoam that helped a little bit. But a little bit only.

But frankly I'm bamboozled. I thought about timing but I'm not sure that's it or? I thought about the choke too but? This winter with record rainfall to spring in a matter of days so I all mechanics are stupid busy and I can't get anyone to even look at it. 3 weeks maybe.

Any thoughts?

[sastanley]

orca...too much..we need to focus.
water in fuel - I had a bad o-ring on the fuel fill...water washing down the side deck got in the tank. - Let's work on trying to solve one problem at a time. I am a proponent of Seafoam, but it is not a fixer for bigger issues. Replacing fuel filter does not fix an issue with the fuel tank..it just slows it down until the filter is overwhelmed again.

My step-father, with a 2 cyl diesel in his boat, enjoyed cruising with me yesterday with the A4, he said, "this is nice and quiet...we can talk while cruising." - so don't rush to a diesel.

I recommend we break things into pieces and solve each one until it is running like a top.

[ndutton]

I forget where I heard it, maybe here but I got a chuckle out of the question to ask when someone is considering such a repower:

What attracted you to a diesel, the smell or the noise?

[lat 64]

Originally Posted by orcaspirit

....However I was getting some crappy/water in fuel (which did happened) and not running right. So I pulled the fuel system and pulled the carb to blow it out and clean all filters bowls etc. Not changing any of the settings. It san okay for a bit but not completely happy. Then running it in anger it was getting worse & worse. A lot of blow by with unspent fuel and exhaust/soot. ... I'm bamboozled. I thought about timing but I'm not sure that's it or? I thought about the choke too but? ....

I do respect a personal choice for diesel, but your A-4 doesn't sound dead yet to me.

Water and crap in fuel:
a diesel will do the same.

exhaust/soot:
a diesel will do the same. Sounds like it's just running way too rich. a properly cleaned and/or rebuilt carb can help. Not just "blown out". There's lots of tiny passages that need proper cleaning and also float setting needs checking.

Your comments say "thought" about these issues. My old skiing buddy always said" if looks could fix it, it'd be running by now"!
That is to say, you need to methodically verify each suspicious condition. LOOK in the intake and SEE if the choke is the problem.
Procedure;

1. remove flame arrestor,
2. pull/push choke lever at controls to full choke setting,
3. look in intake,
4. remark on position of choke butterfly plate.
5. set choke to off position,
6. remark on position of choke butterfly plate.
7. report findings to Forum

Keep calm and dig in,
Russ

[Dave Neptune]

orcaspirit, if you follow the tutelage on this forum you would be a better A-4 mechanic in 3 weeks than you could hire.

Start methodically one step at a time and the A-4 will once again purr away.

I just recently went to a larger boat and I do miss the A-4 for the quiet and downwind motoring odors.

Post a few pics if you can, they really help.

Dave Neptune

[gregsails]

Good to see you checking in Dave. Unbeknownst to you, I followed a lot of your excellent advise
Greg

[capnward]

Neil, I believe that was me, quoting Ray Magliozzi on Car Talk. He was talking to a caller with a diesel in his car, and he asked, "which do you like best, the noise or the smell?" Immediately I thought of the A4 replacement mania.
Diesels get better mileage; other than that, I see no reason to change. I would sooner buy a Moyer rebuild; after 20+ years of learning how these engines work, I don't want to become a diesel mechanic. The junkyards are full of engines that just needed to be tuned up. Like sastanley says, let's take it one issue at a time. You learn more that way.
Orca: sounds to me like you're running too rich. Try rotating the distributor clockwise a bit while running with a load, as an experiment. That will make it run leaner. See if it runs better. If you have an adjustable main jet, it could be turned out too far. It could be the idle screw is turned in too far. It could be the choke is not opening enough. When you had the carb apart, did you inspect the jets for obstructions? To me the usual culprit is junk in the fuel tank. IMO, using non-ethanol keeps the stuff in the tank from dislodging, dispersing, and going downstream to get caught in the filters and the carb. I also recommend electronic ignition, to avoid points and condenser issues.
How many rpm is "running in anger" at 4 knots? If I run mine too hard it starts being unhappy, with more blow by and soot, and little increase in speed. The vacuum gauge is a good indicator of how hard the engine is working. Fuel pressure gauge tells you if there is a fuel blockage.
Orca, you will have better luck on this forum than from a mechanic you have to wait three weeks for, who wants to sell you a diesel. Being your own mechanic gives you peace of mind, but you have to work at studying your engine. This forum is the best place for that, along with the Moyer manual.

[ndutton]

Originally Posted by capnward

Neil, I believe that was me, quoting Ray Magliozzi on Car Talk. He was talking to a caller with a diesel in his car, and he asked, "which do you like best, the noise or the smell?" Immediately I thought of the A4 replacement mania.

Well then I owe you a thanks because it was pretty good.

[alcodiesel]

Capnward, how does this make it run leaner?: "Try rotating the distributor clockwise a bit while running with a load, as an experiment. That will make it run leaner. See if it runs better."

[roadnsky]

Originally Posted by alcodiesel

Capnward, how does this make it run leaner?: "Try rotating the distributor clockwise a bit while running with a load, as an experiment. That will make it run leaner. See if it runs better."

It will RETARD the timing.
To advance move against the rotation of the rotor (COUNTER-Clockwise)
and to back off (retard) the timing, move in the direction of the rotor rotation. (Clockwise)

[capnward]

Obviously my understanding of retarding timing, and it's relationship to the richness of mixture, is lacking. I was incorrect to say that rotating the distributor clockwise to retard the timing makes a leaner mixture. In fact, as roadnsky and alcodiesel suggest, doing so richens the mixture. This counteracts adjustments made at the main jet to lean the mixture. I hope I have that right this time.
I had an episode where the engine would 'diesel' and backfire on shutdown. Somewhere on this forum I found an interpretation of this as caused by too lean a mixture. I had been turning in the adjustable main jet to make it leaner, but apparently had gone too far that way. Rather than turning out the adjustable jet and enriching the mixture, I tried rotating the distributor clockwise a bit, I think because of something I saw on this forum, and the problem went away. I then made a note to myself that retarding the timing enables a leaner mixture. Thus the confusion.
Maybe I should have just turned the main jet back out, instead. I appreciate any further enlightenment on this issue.

[Mo]

Spark Plugs all working??? Just because they are getting fire doesn't mean they are sparking in the combustion chamber.

[orcaspirit]

Originally Posted by orcaspirit

First of all I been through 2 A4 in my boat over a long time period and able to fix pretty much anything A4. Including a head gasket and valve job myself. But I'm trying to coax my engine long until the as my marine mechanic has found a suitable diesel that will work. However I was getting some crappy/water in fuel (which did happened) and not running right. So I pulled the fuel system and pulled the carb to blow it out and clean all filters bowls etc. Not changing any of the settings. It san okay for a bit but not completely happy. Then running it in anger it was getting worse & worse. A lot of blow by with unspent fuel and exhaust/soot. Not proper power because of it. I get 4 knots maybe but it should be doing 6. Very recently I but in a new fuel filter, points, condenser, coil and drained the carb (again!) but still no go. Even tried some Seafoam that helped a little bit. But a little bit only.

But frankly I'm bamboozled. I thought about timing but I'm not sure that's it or? I thought about the choke too but? This winter with record rainfall to spring in a matter of days so I all mechanics are stupid busy and I can't get anyone to even look at it. 3 weeks maybe.

Any thoughts?

Thanks all. Might have solved the problem as it might have the exhaust manifold gasket was slowly pissing saltwater around shorting the electrical system. I got my mechanically inclined buddy believes that's the problem. It's a problem anyway so we are redoing the gasket, dry everything and use some Salt-Away etc. Hopefully it was a slow on going for awhile that's why I couldn't figure it out. Until it quite chronic. Didn't help we got caught in 45 knots going home two weeks ago. My friend thinks this will be it but we'll see once it's done.

Thanks again for your input.

[roadnsky]

Hopefully good news and a solution.
Also... hopefully you're off the "Diesel Re-power" ledge?

[ndutton]

Originally Posted by orcaspirit

Might have solved the problem as it might have the exhaust manifold gasket was slowly pissing saltwater around shorting the electrical system

Hold on just a minute. The manifold gasket does not seal water passages.

[JOHN COOKSON]

Originally Posted by orcaspirit

. However I was getting some crappy/water in fuel (which did happened) and not running right. So I pulled the fuel system and pulled the carb to blow it out and clean all filters bowls etc. Not changing any of the settings. It san okay for a bit but not completely happy.
Any thoughts?

Did you clean out the fuel tank also? Unless the engine is fed a diet of pristine clean fuel it will never run right if it starts at all.
+1 on what Neil said; Don't understand how changing the manifold gasket will solve a water leak. A picture would be helpful.

TRUE GRIT

[marthur]

I just recently went to a larger boat and I do miss the A-4 for the quiet and downwind motoring odors.

My exact situation. Don't get me wrong, I prefer the smell of diesel and there is plenty to satisfy me so I am not complaining. But keep in mind, the new to me Yanmar already has a name: Thumper! Thumper runs!

If it is any help, Thumper stopped thumping on the delivery trip this May because of bad fuel (diesel bug and water). So that is a problem you can't avoid by going to the dark side.

[Dave Neptune]

MIke, which Yanmar do you have and in what?

Dave Neptune

[sastanley]

Originally Posted by ndutton

Hold on just a minute. The manifold gasket does not seal water passages.

Is it possible he is mistakenly thinking of the flange gasket (which also should not be pissing water, but it might in certain circumstances like a blocked exhaust.)

Anyway, let's see what happens next. As Dave Neptune noted, pictures, or a short YouTube video REALLY help a lot.

[Easy Rider]

"A lot of blow by with unspent fuel and exhaust/soot"

I also think he might be referring to the manifold /exhaust gasket.