Rap 24 hp semidiesel, second start attempt.

This video illustrates what happends when these two stroke semidiesels run out due to too much oil in the crankcase. With my left hand, I block the injection pump, so from that time the engine run on lube oil only, no diesel at all. I have heard lots of stories about this from decades ago but this is the first time, to my knowledge, that it is captured on video. Luckily we had blocked most of the air intake prior to starting and ended at somewhat over 1000 rpm. Max operating rpm is 425-450. With full air supply, I would guess this engine would reach thousands of rpm and I could only guess what would have happened then...

The electric glowplug short circuited so we had to rely on the propane burner which had slightly low temperature. In this startattempt, we used an autogen burner and got the glowplug bright red. The crankcase was, unfortunately, filled with too much oil so the engine was running on its lube oil from the crankcase instead of diesel. Still some trouble with the fuel injection, doesn't feel right when injecting diesel manually.

Category:

Autos & Vehicles

Tags:

• Rap
• Rapp
• semidiesel
• semi-diesel
• semi
• diesel
• first
• start
• hotbulb
• hot-bulb
• runaway

[chargerkid5]

I really hoped you learned your lesson for 2 reasons. 1 the overfilled crankcase. And probably more importantly, securing your engine.  The fact that it rocked as hard as it did on your initial attempt to start it should have been a warning to stop and secure it. You're lucky you didn't kill yourself or your friends.

[SveinHaDD]

@chargerkid5 And who are you to judge? I get tired of junk heads who do not dare to touch other than food processors yet know everything about what others are doing wrong with 80 year old ship engines and do not have decency to keep his thoughts to himself...

[angusandleigh]

@SveinHaDD ...the oil level can be an overlook so to speak, but the point he tried to make about the way the engine is mounted is a very valid point. That oversight could have resulted in a severe injury. ..and believe me I work on machinery that's much heavier than a food processor...:) but a cool old engine nonetheless, and good job at shutting it down

[SveinHaDD]

@angusandleigh There are over 100 comments here now that ALL comments engine mounting but no one seems to have noticed that it actually was NOT a problem ... Even when it does not go around but just swings back and forth it have a long way to go before it will fall over.

We did not know how much oil there was supposed to be in the crankcase but we filled up the pick up pipe on the crank, obviously it was too much...

[mikeys205]

this engine has started backwards compared to your video of it running normally.

[SveinHaDD]

@mikeys205 Yes it did. It changed direction 3 times before it got turning over TDC. Same thing, only once, when we got it running normally. When the engine rpm stabilizes, I change direction by shutting down fuel injection at 2:58 and at exactly the right moment, 3.03, I give a couple of manual injections.

[mythril4]

For the future, keep a Co2 fire extinguisher handy or something that can completely clog the air intake. The extinguisher does the same job as a plug in the intake, starves the engine for air nearly instantly, that's how you stop a runaway diesel.

[chargerkid5]

@SveinHaDD And if you would like I can put you in touch with my brother who is restoring a 1948 Enterprise DSG-6 engine. Typically used in ships but this one was built as a stationary unit to make electricity for a town. I am simply concerned for safety. Mistakes happen. But in your video I saw several warnings the engine gave you before the runaway. You should have stopped.

[chargerkid5]

@58Vulcan No probably not. Most of the hydrocarbons have been burned already if it's passed through the engine. But if your oil cooler popped and sprayed directly into the intake then yes absolutely it will run away. As I'm sure you know the only way to stop a diesel is to cut the fuel. The engine will run until the oil quits spraying into the intake.

[chargerkid5]

@SveinHaDD Considering I have a 50HP vertical Fairbanks Morse 2 cycle diesel engine bigger than this one, I figure I have some room to talk.  How many engines do you have. I have 130.

[mrbigtian]

thats is a brave old man.

[DeepFriedFuzzball]

Nice video! It's always interesting to see hiccups with an engine, I had an engine do that to me, an old lister where someone had somehow fudged up the throttle linkage backwards so the governor was increasing the speed rather that decreasing it, much smaller engine than this and it was a paraffin engine, but scared me as it kept running for a few seconds after i'd taken off the plug lead....thanks for sharing though, you were far braver than me with an engine that size i'd have run away! :]

[AussieJeepBasher]

Brown Pants moment that one!

[Polybun]

@SveinHaDD twas just the air in you lads heads.

[browningcal30]

fight of a liftime to get it stopping again haha, I had a small 2cilinder deutz engine that had a runaway, a spring in the dieselpump was broken, it scared the shitt out of me before I could shut it off :D, these moments give you the feeling your alive.

[ChillaxedJosh]

holy shit that flywheel has some inertia!