Blown up engine.

[Mouse]

I wasn't over revving, honest.
Was coming back from getting the MOT at about 55mph and the oil filler cap came off in the dark allowing the oil to spew out and the first I knew was the engine seizing up.


One side of the bore.


And the other.


The piston, one side.


And the other.

Luckily its only one bore that was damaged. Later on today I'll take the sump off and check the big ends.

[andrewaust]

OUCH! That doesn't look good, did you loose all the oil = oil starvation, or is it a case of that cylinder over heating from another cause.

If that cylinder was going down blow by might have popped the crankcase filler, not an accurate assessment though as I don't know much about the engine.


A

[arnaud]

Hmm indeed lack of oil i guess, what type of engine is it?

[Mouse]

Diesel.

[Mouse]

What type of engine is it?

Air cooled V twin 1974 build from a German Multicar M22. It went into many other applications and I believe mine was from a generator.

After some more investigating I found that there was over two litres of oil in the sump (probably closer to three) and doing a bit of minor leaning of the bike and poking up and down with the dip stick I was able to guestimate that the oil level was about only just below the bottom of the dip stick, 5mm below the low marker.

After taking the sump off and measuring some internal bits I found the following...

Oil pickup is 10mm from bottom of sump
Bottom of dip stick 60mm from bottom of sump.
Concluding that the oil pickup was submerged in about 50mm (two inches) of oil so there is not much chance that it ran dry and damaged the bearings. I know that a certain amount of oil would be caught up in the filter and bits with the engine running but there would need to be well over a litre possibly almost 2 for it to drop the oil level to anywhere near 10mm.

I'm a bit happier about spending money on the barrel / piston now.

[andrewaust]

Mouse are you still using forced air for cooling or relying on air blowing by the cylinders when the bike is travelling along. I'm thinking over-heating, then I was wondering why.


A

[Mouse]

Relying on bike passing through the air for cooling.
I was definitely low on oil so there was most probably a lack of lubrication. But if you look at the photo you can see the oil filter is right infront of the side that failed so it might have been a significant contributing factor at the point of failure. .

[IgorVigor]

Might be worth you fitting a couple of small fans to force a bit of air over the engine...

should keep it cooler no matter what...

Computer fans might work

[johnfireball]

Hi,
Looks like lack of oil, I would think your oil level dropped below the level of the crankshaft webs and so was not throwing oil up into the bores hense seisure.
John.