Universal 5411 M15 Diesel losing power/not starting

[valexans]

Hi all! Troubles with M15 5411 Universal diesel on my C 2 27- it randomly started losing power and shutting off after at times hours underway with no issue, finally one day lost power and now wont start and stay running alone after turning over. Will turn over , won’t stay on...I switched out the filters and bled the system to the injectors which shoot out diesel at this point.. still no luck starting and running in it’s own.. there was significant bubbles in the fuel but I think i got it all out.. any thoughts? Could Glow plugs be failing?
So I have basically when the engine started losing power randomly, it would start running at lower rpm then finally die.. which I could then just restart without a problem and she would run for a long time no issues….. so I thought it was the filters so focused on swapping those and bleeding. the previous racor had some gunky nasty residue in the clear casing, so I replaced it and secondary..
So the fact that the engine would lose power at lower rpm’s initially but restart and run is making me look towards the lifter pump and mech fuel pump, like one of those mechanisms “gave out” ?
I couldn’t find a compression lever on my engine while bleeding so just been having a friend crank (intake seacock off) … getting good diesel flow @ secondary filter (past electric lift pump… so seems that’s ok?) and @ injector bleed screw.. here is what the injectors looked like bleeding…

https://drive.google.com/open?id=1-f...S9eqkMc0BEVNsZ


Going to check air filter now. Air intake is open.. there is a little puff of black smoke that comes out of this when engine dies after cranking. At times it will run for 1-3 seconds after letting key go then chokes out and dies..
I did notice my fuel tank vent line is looped at the deck air vent head.. could fuel be trapped in that loop or is that how it should be?
Lastly, how do verify compression level if I don’t have a decompression lever? The reason I thought glow plugs is that they seem to be related to compression?

Been a wind only sailor for always… so motors are a new endeavor for me! Thank you!!

[model 10]

Sounds like a problem I had once, actually twice. One was a cracked fuel line from the tank and it was sucking air. The second time I could see air bubbles in the fuel filter bowl. That was a leaky fuel valve stem.

[Wotname]

Some basic diesel engine pointers

• The engine only needs things to run, fuel, air and compression
• Glow plugs are not required when the engine is running but maybe be required when starting. Some engines require them for every cold start, others only for starting in very cold weather and other don't have them at all.
• Your symtons suggest a fuel issue, possibly a air leak.
• Your vent tube needs to be open to the atomshpere but some fuel in a loop won't affect it.

Good luck with your fault finding.

[bwindrope]

This absolutely smells of a fuel issue. If you have crossed out clogged filters, it is either a vacuum leak, as others have said, or your fuel pump itself. Do you have an electric fuel pump? How old? As to compression, the levers some engines have reduce the compression needed to start by keeping the valves from closing all the way. Glow plugs only add heat to where the fuel injects. Assuming you don't have cracked cylinders or rings that are truly shot, in which case you would be burning oil, then it is just fuel.

If you haven't, it is a good idea to take your injects into a local diesel service shop and have them cleaned. It they aren't atomizing the fuel, you are going to get bad performance. But the engine running and then dying, that is a fuel starving problem.

On my Universal 5432 or M40, there is a little knob by the injector pump that lets you bleed the system of air after changing filters.

So I would look into your electric fuel pump, make sure the injectors are clean, and hope it is not your injection pump itself, cuz that is a very big expensive deal.

[DeepFrz]

Sounds more like a clogged fuel line to me. Is there a strainer on the pickup tube in the fuel tank. If so then get rid of it. Check to make sure the vent tube isn't clogged.

[valexans]

Hi everyone! you were all right!

It was a fuel line issue, I had not been patient enough in bleeding the system. Giving it a full bleed cleaned them all out and finally got clean fuel to injectors.

Back up and running! Thanks!

But as murphys law dictates if if it's not one thing its another.

Now having an issue where engine starts overheating after 45m run, good water flow out of the back, and simultaneously starts filling the cabin with diesel fumes :/.

Looking to systematically check the exhaust system now...

Cheers all

[bwindrope]

Congrats on solving your problem! As simple as our diesels are, they can be remarkably difficult to troubleshoot when you are tracing vacuum leaks. Your overheating problem first has me think your heat exchanger is partially plugged. Or you could have a failed or failing thermostat. They can get stuck closed, and so it takes a while for the engine to overheat. Smelling diesel fumes may be a red herring. That could just be from the engine getting really not. I hope for your sake you have a temp gauge visible in the cockpit and you have been able to turn it off before you got much above 200 or whatever your engine max temp is supposed to be. Mine is a Universal 5432 or M40, a sister engine to yours. If you run it hot for long, you can be doing damage you'd rather not think about. So I'd first replace thermostat, because they are cheap and easy. Then also check heat exchanger. It can be partially blocked and you still get good water in exhaust, as our eyes cannot discern a 10% reduction in flow.