Bukh DV20 woes... hard to start, and now....

Some older diesels also had a butterfly in the intake manifold which acted as the throttle, rather than the more common fuel pump control.



My concern with putting fuel in the oil was not centered around an engine runaway. I'd prefer to use cheap oil/flushing oil, rather then pumping a fuel/oil mix through my bearings etc. As a general rule it's not a great idea to pump poor oil through shelled bearings. Deliberately making contaminated oil even poorer by mixing in fuel doesn't seem like too sound a policy to me.

Confucius say, oil is cheaper than metal :)


Diesel fuel has the capacity to lubricate the micro clearances inside the mechanical injector pumps. To suggest that when mixed with oil it would not lubricate the bearings is ludicrous. Mechanical injector pumps are very expensive units.

I take your point about flushing oil.

Have you tried to obtain any recently? Hard to pick it up on the high street these days.
 
Some older diesels also had a butterfly in the intake manifold which acted as the throttle, rather than the more common fuel pump control.

You do rather come out with some nonsense at times!

The idea of a butterfly in the inlet tract is to create manifold depression. The vacuum then produced controlled the fuel pump rack ala Mercedes OM.

CI engines do not work on carburettors you know.

Yawn.

The mods have told me not call anyone a bell end, so i won't.
 
Pretty normal human response from a person who has exhausted reason and knowledge in a debate, to discredit their peers in a personal attack. Most applicable, I am assured, in the pre-pubescent with a low to mid IQ.

Subject closed.
 
This is exciting! - Wondering whether or not the Punch and Judy show will last until Stevie69 has saved up enough to buy the Bukh head set, rebuilt his motor, reports back and we find out if it's cured his problems. :rolleyes:

LOL...

Head set has arrived... just waiting on the second hand head appearing. Watch this space haha...
 
Well just to update the thread, I am happy to report that fitting the replacement used cylinder head plus all new gaskets has been a success. I got her fired up at 7pm yesterday with fresh oil in the sump. Carried out checks this morning before taking the boat out for approx 2 hours using the engine, and all is well. Changed the oil again, so hopefully most if not all of the contamination has now been pumped out.

Thanks to all for comments and advice, even if the oil / diesel thing started a wee rammy...
 
Nice one! All's well that ends well.

Indeed!

Though I did have a small 'moment' when I dropped a copper washer down the pushrod gallery after having fitted the head... Fortunately I could see it and removed the rocker shaft and a couple of the pushrods, and used a wire coat hanger with a blob of butyl tape on the end to stick to the washer and fish it out... Other than that it all went well, though a long day.

Looking forward to some better weather and decent sailing now :cool:
 
Well done! I was wondering how your cylinder head got a crack - maybe a bit of frost?

It's hard to know exactly. The boat has been in the water all winter but we haven't had really hard cold temperatures, not enough to freeze sea water anyway, though I think I will take the precaution of draining it down next time just in case.
 
Hi
I have had all of your problems with my 1973 DV 20 . The water pump was letting a small amount of water into the engine but the main fault lay with the head gasket. The lock up of the engine was caused by water in the cylinder creating a hydraulic lock. I managed to clear this using decompressor. The engine was then stripped and rebuit as in my video links below with help of a Workshop Manual .


https://youtu.be/7mO7wRKoKCM

https://youtu.be/PmTjwYOAT-8

The engine is now reliable but as the engine is quite old now. In cold weather I remove the air cleaner and squirt a drop of oil from a oil can into each cylinder via the inlet manifold. I allow about 10 secs with decompressor and release . Starts straight away every time. Hope this all helps.
 
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