Possible cause of engine not running...

[Wisakedjack]

I'd like to ask for opinions on what may have caused my engine to stop running. It is related to the other thread I started:

https://www.moyermarineforum.com/forums/showthread.php?p=127227&posted=1#post127227

but that discussion turned into figuring out why the engine does not start now. I am still curious how it all got to this point.

Here is the sequence of events:
1. Engine started and run great all summer. There was no hesitation and it did not run rough at any point.
2. Then my fuel pump went bad. There was a burnt plastic smell. Pump did not click and gauge in output line showed no pressure.
3. I got new fuel pump from MM and replaced the failed one. Engine started up fine. I run it for about 30 minutes and then motored for a bit around the mooring field. No problems at this time and I did not see any changes from how engine run before.
4. I come back few days later. Engine starts fine, runs for 10 minutes and just shuts down. I could start it again, but now it died after 30 seconds or so.
5. When I come back few days later to troubleshoot engine won't start. New fuel pump is working (based on gauge reading) and I have strong spark from coil. No modifications other than changing fuel pump were done at this point.

What could cause this? Going from perfectly working engine to not starting at all engine. While I can think of several reasons why the engine would not start, I keep thinking what are the chances of having fuel pump issue and failing to start issue pretty much at the same time? I am ready to accept the answer that this just happens, but I am interested in other theories too

[Al Schober]

Most favorable assumption is that the issues are related - otherwise you have a new problem. Perhaps some debris from the failed pump found its way into the carb? Likelihood of this is increased if there's no secondary filter between the pump and the carb.

[Wisakedjack]

Al, I do have a filter between pump and carb. I cleaned up carburetor in the aftermath and did not see anything unusual.

[Mo]

Sounds like you have fuel, spark and cleaned the carb. By cleaning the carb did you remove it and clean the jets. The main jet plugged will stop it from starting. I'd suggest changing that fuel filter as well and ensure all fittings and clamps are tight.

Check that the choke is working properly. Next thought would be fuel pump failure but if you have pressure on a gauge that pump is good. New electric fuel pumps can go bad occasionally, but your gauge says it's OK if you have pressure.

If you have done that the next check would be check compression. You would have ruled out fuel, spark, and air. This scenario could happen: boat wouldn't start, turned it over with RAW water intake open. Water, on some exhaust layouts, could run back, get around the valves and seize them in a few days. If the cylinders lost compression no amount of spark or fuel will allow it to start. We have updraft carbs and they need compression to draw the fuel up to the combustion chamber.

Another thought would be a shot of ether and see if it starts...if so, fuel issue. When I say a shot it's just that, a short shot.

EDIT: re spark. You have strong spark from coil. You also need to check spark at each plug...you probably did that but just making sure there isn't a problem between the coil and the plugs.

[zellerj]

Fuel, spark, compression, and timing. Are you sure about the timing? Could have the distributor moved?

[Wisakedjack]

Thanks Mo and Jim for your suggestions. I will look into compression next time I get a chance. My fuel pump is new and I did not touch the distributor. I do admit that in 7 years that I had this boat I never opened distributor cup (I have EI). The cup does not seem to have any cracks. I don't know how often cup and rotor should be replaced. I did see them both mentioned as last thing to try to Moyer's shut down troubleshooting video.

[Ando]

How is your oil pressure (at start, when warm and after ~30mins)?

[sastanley]

If you have not had the cap off in 7 years, I HIGHLY recommend you pull the cap, rotor, and the EI plate and make sure the advance weights are working properly. If they get stuck "advanced", the engine will be hard to start and will only run WOT, which is where the weights get stuck. For right now, you could pull the EI plate and maybe squirt some WD-40 or other penetrant in there to see if you can get the weights to move freely. There are actually two shafts in the distributor...you should be able to rotate the rotor by hand 17 degrees or so and it should snap back if the weights and springs are working correctly. I had a lot of corrosion in there and things got stuck advanced, which meant it would not start. If you pull the EI plate and then re-attach the rotor and put some pressure on it, it should move that 17 degrees or so, and you should see the weights move out, and back in when you let the pressure off....it is like a flick motion..17 degs is not much, but critical.

[Wisakedjack]

Shawn, thanks for the suggestion about weights. I meant to look at them since last year. I finally did it and did not find any issues. Springs were in place and weights were not stuck. I did lubricate them with WD40. The problem with engine not running has been resolved. It just started and run fine after I fully charged my batteries. So, as Neil correctly suggested my coil voltage was not adequate. Now here is my theory of how I go to the point where engine was not even starting. Batteries got discharged over the summer even though my electricity usage is minimal. We had a storm for few days before that day when engine stopped working. My boat is on the mooring where it does get pretty rolly. When I boarded the boat that day I noticed that the bilge pump was running even though there was not much water in the bilge. I attributed it to wave action and water slushing in the bilge and did not pay much attention to it. Few weeks later I looked more closely into it and found that my bilge pump switch (I have Water Witch not a float) was turning on the pump even though its contacts were not covered in water. I think this was caused by having some oil in bilge water. Where its coming from is another issue. But I did read in the past that oil may cause Water Witch to keep pump turned on. I think running pump drained the batteries. Now when the engine run last time the alternator did not kick in (I need to rev up engine to get alternator charging) and it just drained rest of the battery to the point where ignition voltage was too low. Do you guys think this is a possible scenario?

[capnward]

That scenario sounds not only possible but likely. My Water Witch does the same thing. It takes very little oil in the water to make a connection to the bilge pump. I seem to recall reading that A4s have no seal where the crankshaft exits the flywheel end, only a bearing which leaks oil slowly. If you tilt an A4 full of oil too far forward, it will drain past the bearing and make a mess. I try to remember to put an oil pad under the flywheel. I think I will go back to a float switch. You might want to look into a solar panel, since you are on a mooring.

[Wisakedjack]

Thanks for sharing your experience capnward. I am not going back to the float switch. I had it before I installed Water Witch and it had issues with getting stuck. A friend recommended this switch:

https://tefgel.com/contain.php?param=pumpswitch_price

Its costly, but multiple sources swear that it works really well. I am not getting it just yet. I am getting a solar panel installed as you've suggested. I am looking into an oil leak issue. I suspect it may be originating from the water pump that was not serviced in about 8 years. I also need to redo shaft seal packing, which may reduce amount of water I have in the bilge. I am going to be busy this offseason

[TimBSmith]

One other question...great to read this progression...

You don't mention here, maybe I missed, did you replace your batteries? How run down were they? What type? How configured? Voltage? What was your approach to monitoring battery charge or trickle charging when you were off the boat?

Appreciate where this exploration has lead. I absolutely obsess about my solar panel and charge regulator. First thing I check when I am back on boat is charge level on regulator. Gross early indication of unexpected loads or battery failure. My bilge pump is not wired direct to battery with fuse. It is wired into the main positive bus, not panel, with fuse and the selector switch has to be on in order to run it. PO EE wired things thusly.

I have heard great discussions on direct wiring with fuse and I am considering it. My bilge pump is of the cyclic sampling type. I also like the wireless/cellular monitoring that some are doing with onboard sensor and transmitting text messages. What has been your approach?

Thankful.