coughing carburetor after electronic ignition install

[RossBarker]

Hello everybody,
My name is Ross, and I am recently new to this forum. I own a C+C Redwing 30 with an atomic 4. I bought my boat around 4 years ago and ever since I've had problems with the engine stalling out. It will run great for around 2 minutes before it starts to sputter and eventually stalls out. The guy that I bought it off of did not take it out for about 2 years so the boat was sitting unused for a while. I just recently changed my point system to electronic ignition and retimed my engine, and since I did that, the engine has been stalling out a lot quicker, my carburetor is coughing out gas, and I am getting little power when it does run. I am new to fixing engines and don't really know where to start. I figured I'd come to this forum to get some questions answered. It is greatly appreciated!
Thank you
-Ross Barker

[capnward]

Welcome to the forum. You have come to the right place. Start with the carb. Sounds like a fuel delivery issue. Time to remove the carb, remove, inspect and run thin wires around in the jets especially the idle jet, and put the carb back on with new gaskets. Also dress the seat of the float valve with the wooden dowel available in the Moyer carb rebuild kit and clean the carb interior. The float adjustment should be checked. At the same time replace any fuel filters. I do this process every spring. This is a good thing for an A4 owner to know how to do. In my experience fuel issues are the most common. Get a Moyer manual if you don't already have one. There could also be an exhaust blockage but that is less likely. Or possibly the fuel tank vent is clogged, preventing fuel flow.

[Dave Neptune]

I think you may have a couple of issues. First is the timing, changing out to an EI will require you to get the timing properly set again. Timing could be part of the reason for the carb spitting out fuel. Does the centrifugal advance work smoothly IE does the rotor twist easily and spring back smoothly?

The engine stalling out after a couple of minutes indicates that the carb is starving for fuel. It takes about 2 minutes to run the fuel out of the carb bowl which could be the fuel pump or the filters. Check the filters and it would be a good time to install a cheap fuel pressure gage which will help now and in the future.

Dave Neptune

[RossBarker]

Thank you for your responses! I thought it was a carburetor issue as well and thought that it could also be a fuel issue. I changed my fuel filter a couple of weeks ago along with the lines, I took out all of the dirty gas from my fuel tank, and put new gas in. I also took apart my carburetor, cleaned out all of the dirt with carburetor cleaner and put it back together. I don't believe I have an exhaust blockage since I took my front head and exhaust manifold off last year to clean it and replace a couple of valves. I followed the Moyer marine carburetor troubleshooting video on youtube as best as I could. I think the next step would be to redo the timing on my engine to make sure it's on point since my carb only started doing this after I installed my electronic ignition and retimed it. If that doesn't work I will look into getting a new fuel pump. I just want to try other things that could help before spending money on a new fuel pump that might still be working well. Unfortunately, my temperature gage, and oil pressure gage does not work so its tough to see those underlying problems that might be causing the stall out. Someone suggested to me that I change my water impeller.

[Al Schober]

Ross, Welcome to the forum.
That '2 minute' thing sounds like the time to suck the fuel out of the float bowl.
Over my years of A4 ownership, I became very aware of fuel issues - more so with the prevalence of the Ethanol additive. More on that as warranted.
I recommend adding a pressure gauge to the fuel inlet to the carb. It tells you immediately whether you have a carb problem or a supply problem. A 5 psi gauge is fine if you can find one. Finding a 15 psi gauge will be easy on Amazon. Something small (1"?), metal, preferably with a glass lens.

[roadnsky]

Hey Ross-
Welcome to the gang.

Question...
When you changed over to EI did you take the distributor completely out?

[ndutton]

Addressing the coughing symptom, I can think of only one cause for that: combustion with the intake valve open. This can happen with a sticking intake valve or with ignition at the wrong time. I suggest a compression test for the former, a reset of the timing and firing order recheck for the latter.

[tenders]

Also make positively sure you reattached your spark plug wires in 1-2-4-3 order. It is easy to get them confused in the excitement of adding Star Trek-level electronic ignition technology to the humble A4, and it creates an instant quantum timing problem.

If you find your valves are sticking a little - or even just to pre-address this potential issue, which is common - you can add 2 ounces of Marvel Mystery Oil per five gallons of fuel and reduce that risk.

I have done this on all the fuel going into the tank for several decades now and can tell when the MMO isn’t in there. I also ALWAYS add Sta-Bil fuel stabilizer, and have (knock on wood) avoided all stale fuel issues, even with ethanol fuel, which is all we can get in these parts.

Pro tip: use an empty bottle of Sta-Bil to store the onboard MMO. It has a cool and very useful 1-ounce measuring doohickey molded right into the bottle. I bet it works well for tequila shots too but I don’t know how to get the Sta-Bil taste out first.

[RossBarker]

Thanks again everyone for your input. Today I went to the boat and retimed my engine with the electronic ignition, it was still doing the same thing. I then switched back to the old coil system on my distributor and still was doing the same thing. I made sure the spark plug wires were in the proper order. I then took my carburetor out again and talked to someone in my marina, he did a blowing test in the holes that a couple of jets go into and said that the air wasn't moving freely at all through the chambers, so I'm going to clean it out and see if it works better tomorrow. This makes sense for both issues I'm having because if fuel is getting blocked inside my carb that would cause the stall out and leakage.

[RossBarker]

Well, after cleaning my carburetor twice, its still doing the same thing. I did a compression test in all spark plug holes and they all seem to have compression. My spark plugs were getting pretty rusty, and they were wet with fuel, I changed my spark plugs today and also changed the oil (made no difference) My oil came out grey, which i'm not sure if that is normal. I'm really getting stumped on this one and definitely thinking about buying a new fuel pump. Although at the same time that wouldn't affect my carburetor spitting out fuel.. I also probably have to change my water impeller, since it has not been changed out since I bought it 4 years ago, although I do seem to be getting a decent amount of water coming out of the stern of my boat. One thing I haven't done yet is dress the seat of the float valve in my carb with the wooden dowel that I don't have.

[Dave Neptune]

The grey oil means that water is getting into the engine. If it is getting in the combustion chambers it will not run as the moisture grounds out the voltage from the coil and so no spark in the chamber.
Time for a good compression check and a possible leak down test.

A proper compression check is as follows, batteries fully charged, throttle wide open and all plugs removed. Record the numbers and do it twice.

ANY FURTHER work done should be done with the water intake valve closed. Excessive cranking with the valve open will allow water to get in through the exhaust valves.

Did you try any starting fluid during any of your attempts?

Dave Neptune

[RossBarker]

I did a compression test today and there was 90 psi of compression in each spark plug hole, which was after holding the starter for about 3 seconds. How would I do a leak test?

[Dave Neptune]

Need info

Ross, there are a few ways for water to get in the crankcase.

First and easiest to fix is leaving the water intake open during log periods of cranking and not start. Have you had the valve closed?

Second is a breach inside the intake manifold which can be pressure checked easily.

Third and most catastrophic is a breach in the block usually at the bottom of a cylinder. This can be checked by pressure testing the block. A bit more work then the manifold test but the same type of test.

Did you try any starting fluid?

Were the plugs wet with water and still smelled like gas?

For good advise we need some answers.

The compression looks good so it does not look like the head gasket is breached, a good thing.

Dave Neptune

[RossBarker]

Dave I really appreciate the help you are giving me. When I did my compression test, I made sure to close the water intake valve. I used starting fluid a couple times but it didn't seem to help other than the engine starting a little harder than normally. When I pulled the spark plugs out, they seemed to be pretty rusted, and yes, they were wet, black, and smelt like gas still. I will have to check the pressure of the intake manifold. You do this by opening the water jacket right?

[Dave Neptune]

Ross, there are many threads on this site on pressure checking. First we need to clear up if you had the water valve open during any of the cranking. Cranking with the valve open allows water to back up in the exhaust as there is no "exhaust" to force it out. then the water leaks in through an open exhaust valve, not uncommon. Think about it.

To pressure check requires a bit of work but not much. You isolate the water jacket of the manifold by pulling the water hose of each end and blocking one. Then you pressurize the other to see if it holds pressure. A few ways to do this.

Get back before doing the pressure check with an answer regarding cranking with the valve open.

Dave Neptune