Lost a nut down the crankcase today...how f.ed am I ?

[Spiff]

So basically what has happened is I gently nudged my coworker into buying a 80' GSX750 that needed some work and I've agreed to help him fix it.(Subcontiously I'm probably itching for another project but don't have the space at the moment)
The engine was leaking oil everywhere and after pulling the cylinderblock and replacing the base gasket and orings we went to put the block back in and we used a couple of hose clamps around the piston rings... But in order to remove these they had to be dismantled and that's when I lost a nut down the crankcase through cylinder 2's hole...
I scavenged around with a magnet down there but to no avail, the crank turns so it's not stuck on any rotating bits, next step is to drop the oil pan but what if it's not in the oil pan???

[unfocused]

From the cylinders it's only option is the oil pan. Especially #2

After purchasing a Katana 750 parts bike for a project I removed the ignition cover to rotate the engine. Now this engine was installed in my project and running/driving then removed for frame finishing and other tid bits. Well 2 screws were missing out of the ignition plate so off comes the oil pan... Where did the nut/washer come from ???

Come to find out, that's the nut/washer for the alternator drive gear. Only found one ignition plate screw and gave up looking as I'm sure it was found prior to my ownership or never installed.


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[Brendan W]

You could try pushing the magnet in under the starter clutch.
There is a gap there through to the crankcase.
I pulled a starter idler gear washer out of an 850.
Who knows how long it had been there.

[oldGSfan]

Is the magnet the flexi type? If not I'd try that, cheap and handy to have. In the US the AutoZone parts store rents out a borescope, which has come in handy for me a couple of times. Maybe not able to borrow in Norway tho.

[Spiff]

Is the magnet the flexi type? If not I'd try that, cheap and handy to have. In the US the AutoZone parts store rents out a borescope, which has come in handy for me a couple of times. Maybe not able to borrow in Norway tho.

I actually bought a boroscope last year, if he doesn't find it after dropping the sump I guess I'll bring it out and have a look in there

[Spiff]

Okay so here's the latest update, he didn't find the piece when dropping the oil pan. He borrowed a boroscope but couldn't find anything so three days ago I went to see If maybe I could find something.
I tried fingering around whatever hole and crevass I could get my fingers into but didn't find anything. I used my boroscope but couldn't see anything. We took out the clutch assembly to try and see anything from that side; nada... We even laid the bike completely on it's side and listened for anything that might move; nothing. We pryed and poked around in there while it was on its side but nothing.
I tried to use a dentist mirror to see anything but still couldn't find anything. He's gonna try one last thing now and that is using his compressor and air gun to blow around in there to see if he can hear anything or see anything move...
But if this proves unsuccessfull then what? Assume it's not there and that it bounced on the ground and was lost in clutter or kicked around? Assume it came out when he drained the oil and that it is laying in his drain pan? We took the oil and transfered it to a clean jug but didn't see anyting there either... The whole thing is quite baffling.
I said maybe he could remove the spark plugs and then try and spin it on the starter a couple of times. We've turned it by hand god knows how many times without it locking up or without hearing anything move so if it where my bike I'd take the chance and send it, but it isn't mine so I'm not sure I wanna give that advice
Also the nut is stainless so not magnetic... what do you guys think?

[chuck hahn]

I wouldnt use the starter to spin it. IT wont stop if something jams and it will break stuff. Use the 19mm nut on the timing cover and have manual control in case something jams up

[Spiff]

I wouldnt use the starter to spin it. IT wont stop if something jams and it will break stuff. Use the 19mm nut on the timing cover and have manual control in case something jams up

We've done that several times now like I previously wrote. Nothing jams, can't hear nothing rattling, nothing out of the ordinary

[rphillips]

No way to know for sure. Are you familiar with Clint Eastwood in the movie "Dirty Harry" he probably had as good of answer as you'll find.

[Spiff]

Yeah I guess so. Tried blowing around the crankcase with an air hose but he didn't hear nor see anything so by now I'm thinking just send it and if it blows up, get an 1100 engine