Engine seems to start but rolls to a stop

[Wotname]

^^ good luck with today's mission!
Looking forward to your next report.

[JustinT]

Here is the oil. Looks clear. Maybe too clear?
https://youtube.com/shorts/YNe9w0Jgy...3Gvt66Fbl7kKL-

And here is a start with no exhaust connection
https://youtube.com/shorts/Ywb2J8Yzi...o2Fk8G0mnot6G5

What is that box on the exhaust line? Mine can't be opened, assume a silencer of some sort.

[JustinT]

I also opened the lift pump but there appears nothing inside it... probably need to remove it entirely...

[deblen]

Originally Posted by JustinT

Here is the oil. Looks clear. Maybe too clear?
https://youtube.com/shorts/YNe9w0Jgy...3Gvt66Fbl7kKL-

And here is a start with no exhaust connection
https://youtube.com/shorts/Ywb2J8Yzi...o2Fk8G0mnot6G5

What is that box on the exhaust line? Mine can't be opened, assume a silencer of some sort.

All of what Wotname said-great comments !!.


IMHO-I watched the above 2 vids. Looks like oil is new-no sign of water.
Sounds like a "spitting" sound while cranking and also while running-indicates a possible "puff" of compression leaking :
a. thru a poorly seating intake valve(puffing back thru air intake)

b. sticking or mal-adjusted(too tight) intake valve ( "")
c. Leaking exhaust valve(as above) puffing thru exhaust pipe(not likely,as there would be puffs of white un-burnt fuel also.
d. mal-adjusted decompression control on one cyl(holding a valve open
e.my imagination because I know you have been all over that stuff,but.....



Good idea to leave exhaust hose off at present-can see & hear symptoms better.
The "box" on exhaust line would be a "marine waterlift muffler/silencer"-google it for description of operation.


You mentioned fuel lift pump.
a. was there a screen & was it dirty?
b. does it have a lever on the side to allow you to manually pump/ prime fuel? c. does it pump fuel? or is diaphram/check valves faulty? Is the operating arm working the diaphram(try operating with hand)
d. is fuel pump cam in engine operating?


You could try gravity feed of fuel from a soda bottle? tank with hose leading to HP pump inlet.



As Wot said-read the manual until you understand the operation of each item you are preparing to work on-preferably before you "work" on it. That way,you can't blame anyone but yourself & we don't have to charge extra for fixing your mistakes
Len

[JustinT]

IMHO-I watched the above 2 vids. Looks like oil is new-no sign of water.
Sounds like a "spitting" sound while cranking and also while running-indicates a possible "puff" of compression leaking :
a. thru a poorly seating intake valve(puffing back thru air intake)

b. sticking or mal-adjusted(too tight) intake valve ( "")
c. Leaking exhaust valve(as above) puffing thru exhaust pipe(not likely,as there would be puffs of white un-burnt fuel also.
d. mal-adjusted decompression control on one cyl(holding a valve open
e.my imagination because I know you have been all over that stuff,but.....

I had a period when bringing the yacht to Lochcarron that loads of oil came out, in the end I decided this was because I overfilled it. I think that is why I ended up with lovely clean oil.
After the video I re-gapped an exhaust and inlet valve and the spitting stopped. One of the decompression levers needs to be extra pushed away until that end fires. They are both wound right away, though I have been wondering if one is fouling the rocker.

I was thinking of removing the air filter too, as you say, I could hear so much more engine stuff with the exhaust removed.

Good idea to leave exhaust hose off at present-can see & hear symptoms better.
The "box" on exhaust line would be a "marine waterlift muffler/silencer"-google it for description of operation.

Thanks


You mentioned fuel lift pump.
a. was there a screen & was it dirty?
b. does it have a lever on the side to allow you to manually pump/ prime fuel? c. does it pump fuel? or is diaphram/check valves faulty? Is the operating arm working the diaphram(try operating with hand)
d. is fuel pump cam in engine operating?

When I operate the lever fuel comes from the screw on the filter, as it is supposed to.

Thinking to remove it and go over it but access is near impossible. Taking the cover off it seemed very clean inside.


You could try gravity feed of fuel from a soda bottle? tank with hose leading to HP pump inlet.

That's a very good idea.



As Wot said-read the manual until you understand the operation of each item you are preparing to work on-preferably before you "work" on it.

Indeed, I do pour over the manual, keep thinking to print it out.

That way,you can't blame anyone but yourself & we don't have to charge extra for fixing your mistakes
Len

[deblen]

I noticed,in video,that a decomp. lever moved slightly when you started cranking.Not familiar with your engine-could be normal,but.....

[deblen]

OH-if you leave valve/rocker cover off,that could help you see/hear things also.
Did you cure the oil squirting from rocker lube pipe yet?

[deblen]

Source of marine engine manuals :



https://marine-diesel-engine-manuals.com/



https://marine-diesel-engine-manuals...gines/bukh.php

[JustinT]

Originally Posted by deblen

OH-if you leave valve/rocker cover off,that could help you see/hear things also.
Did you cure the oil squirting from rocker lube pipe yet?

The pipe is done and I'll collect it tomorrow.

If I leave the rocker cover off it seems un-inclined to do anything.... though I could try that again

[skipperpete]

Originally Posted by JustinT

The pipe is done and I'll collect it tomorrow.

If I leave the rocker cover off it seems un-inclined to do anything.... though I could try that again

You’re making great progress although I was a bit puzzled by the lack of smoke when you ran the engine with the exhaust hose off. I occasionally do this and never fail to fill the workspace with acrid smoke.
I’ve been watching your Youtube channel would politely suggest you refine your camera work and either add subtitles or a bit of dialogue, the members who’ve been contributing to your thread can follow the vid and understand why you’re posting it but the wider audience on youtube probably won’t have a clue what to make of the jerky footage of an oily chunk of machinery without narration.

[JustinT]

Originally Posted by skipperpete

You’re making great progress although I was a bit puzzled by the lack of smoke when you ran the engine with the exhaust hose off. I occasionally do this and never fail to fill the workspace with acrid smoke.
I’ve been watching your Youtube channel would politely suggest you refine your camera work and either add subtitles or a bit of dialogue, the members who’ve been contributing to your thread can follow the vid and understand why you’re posting it but the wider audience on youtube probably won’t have a clue what to make of the jerky footage of an oily chunk of machinery without narration.

Oh there was smoke, enough to fumigate me.
Ah the channel. When I've got the engine to work I'll go back and edit the descriptions. The first few I did so but, the repairs are taking up nearly all of my (spare) time.

I feels like a wierd sort of "progress" maybe one step forward one back...

[GrowleyMonster]

Looks like u getting very good advice in my absence. Absolutely, try gravity feed CLEAN fuel directly to injection pump, bypassing lift pump and engine mounted filter. Yes the peripherals are important but right now more important to ISOLATE the malfunctions, beginning by bypassing everything and making absolutely sure that the key component of your fuel system is delivering high pressure fuel to the injectors in a dependable and sustainable manner. Then work backwards from there verifying parts of the system are doing what they should be doing.

Once you verify injector pump, replace all hoses. Hose is cheap. Old hose can collapse without you being aware of it.

When it dies, did you immediately follow the bleed procedure? You should get fuel coming out immediately from both injector lines if engine was just running and if not, you are either fighting a vacuum from blocked tank vent or collapsed hose or closed valve, or else air ingress through poorly sealed connection or a leak somewhere. Bypassing components one at a time will find the problem if it is a fuel starvation issue. So connect your fuel bottle directly to engine mounted filter, then directly to lift pump, then directly through primary filter. Then replace the pickup tube, then inspect and clean the tank, and disconnect vent hose from tank. That's how you find problems in a linear system. Start at one end and verify. Split the system at some point and verify that part of the system. Follow hand over hand the wires, pipes, or hoses of the system. You can often cut to the chase by replacing the usual suspects or the cheap stuff like cable or hose or pipe, or the stuff that is simple to change. Be analytical. Be observant. Channel your inner Sherlock Holmes.

[JustinT]

Thanks Growley
When bleeding I watch the fuel squirt/pulse from the injector connectors.
Thing is, the engine was running before, so the issue developed and no alterations took place ie fuel tank
So collapsed/blocked pipe or another blockage seems possible.
What troubles me is the running out of control issue, the way it's not idling.
I shall by trying the bypassing the lift pump etc as it's been worrying me all along, especially as the lift pump is so hard to get to.

[skipperpete]

Originally Posted by JustinT

Oh there was smoke, enough to fumigate me.
Ah the channel. When I've got the engine to work I'll go back and edit the descriptions. The first few I did so but, the repairs are taking up nearly all of my (spare) time.

I feels like a wierd sort of "progress" maybe one step forward one back...

More like one step sideways than back, you’re not losing ground, just pausing to learn new things then moving forward again. Keep up the good work.

[JustinT]

Originally Posted by skipperpete

More like one step sideways than back, you’re not losing ground, just pausing to learn new things then moving forward again. Keep up the good work.

Thanks, yes, it is progress... it's certainly changed how it is complaining at me! I'm quite surprised I added fixing 50 year old diesels to my CV