Looks like a float bowl screw, But that wouldnt end up there. Everything else is a allen type bolt.
Who worked on your bike last?
Id pull the plugs ASAP, Once you know everything is clear do a leakdown and a comp check.
Have you messed with any vac lines to the tank?
I'm assuming it was the previous owner. Bought it a few thousand mi ago back in June from a local guy who def did some wrenching himself. Could've been him or the shop who did the valves at 12K. (currently has ~17K).
Could this be why it's hydro-locking and/or fuel is running down into the oil?
I haven't messed w.any of the vac lines, nor anything else for that matter. Just let it sit a few wks, tried to start it and the problems began.
Will have to bring it to someone for a comp. check I guess. Don't have tools with me to pull the plugs either so I'll do it and report.
Could this be why it's hydro-locking and/or fuel is running down into the oil?
Thanks.
not unless there is a hole in the piston. Take a picof the vac lines when you get a chance. Also take the charcol can off. See if its filled with fuel as well.
that does not look like the culprit. if it had been locking up the crank or tranny gears it would look much worse than that and you would find gear pieces on the magnet also. It had to fall into the head during service or come from something internal to get into the oil pan, without going through the motor. Something that big would not get through the motor in one piece either.
Verify what is wrong before you just break it loose and go on your merry way. It is too easy to ruin the bottom end with contaminated oil. Is the exhaust wet when you get it started? You can pull the plugs without taking off any plastic. When it is locked up, pull the plugs. Fuel will either run out of the front cylinder or spray out the rear when you turn it over (by turning the rear wheel by hand). DO NOT LOOK INTO THE SPARK PLUG HOLE WHEN YOU DO THIS!! Fuel will spurt out quite forcefully.
If you do nothing else, turn off the fuel under the tank when you park it. It takes less than a minute and no tools except opposable thumbs.
Is the exhaust wet when you get it started? You can pull the plugs without taking off any plastic. When it is locked up, pull the plugs. Fuel will either run out of the front cylinder or spray out the rear when you turn it over (by turning the rear wheel by hand). DO NOT LOOK INTO THE SPARK PLUG HOLE WHEN YOU DO THIS!! Fuel will spurt out quite forcefully.
If you do nothing else, turn off the fuel under the tank when you park it. It takes less than a minute and no tools except opposable thumbs.
Good luck, Dan
Exhaust is not wet and even with my face literally in it, it doesn't reek of fuel. The bike does smell much stronger of fuel than this (partic as an older bike) normally does.
How do I shut the fuel under the tank? Is there a valve or something to control it there? I'm happy to begin doing this, just never done it nor do I know what to look for (i.e. on what lines, etc).
Exhaust is not wet and even with my face literally in it, it doesn't reek of fuel. The bike does smell much stronger of fuel than this (partic as an older bike) normally does.
How do I shut the fuel under the tank? Is there a valve or something to control it there? I'm happy to begin doing this, just never done it nor do I know what to look for (i.e. on what lines, etc).
Thanks!
under the tank is a screw valve. Just turn it in til its seated.
under the tank is a screw valve. Just turn it in til its seated.
Did you check the canister for fuel?
I think I noted this in the original post (?) but last week, the 2nd time this seizure, etc happened, once it started there was fuel stink and little bits of fuel spitting out of the canister/head pipe junction (i.e. where the slip-ons insert). There was enough to form a very small wet spot on the ground beneath. This happened at both pipes, worse at the lowside junction (forget which valve that makes it). Didn't see or smell it in the canister itself so maybe it didn't make it that far up/out, but it was in the neighborhood.
After a few minutes the fuel spitting stopped and I was off, with no more problems for two days. Then it sat over the weekend, for 3 days, and today same problem (but no fuel spitting).
first: check for rust in the tank, look through the filler with a flashlight at the rear corners especially. Rust dust and flakes can let fuel run by the float valve. If you have rust, take the tank apart and use the POR-15 tank kit on it. Follow the instructions it is easy.
second: more difficult, change the fuel filter. I have removed the in tank filter on my bike and replace it with rubber hose. I put a Russell inline filter in the external hose, now cleaning the filter (ceramic media) or changing the filter is much easier. It is amazing how much rust dust would be in the filter prior to doing the tank liner from POR.
The tank is clean and there actually is an inline filter down the line and it's clear.
Same drill this morning upon start. Fuel level in tank does seem to be dropping much more quickly than before these symptoms began - that is, until I shut the screw valve under the tank this afternoon. We'll see if it makes a difference, though I'm sure the fuel is mostly cranking out while engine running.
She ran fine today, as usual, but we'll see what the morning brings, after the 1st night of keeping that screw shut.
My first Ducati and my first racebike was a 1993 750SS with 39mm KeihinFCR's and some other mods, great bike.
If I were you, I'd just give it a full fuel system over haul. Get those carbs off and clean 'em. Replace the float needle and give yourself some new fuel lines in and out of the tank. FCR's are notorius for leaking fuel past the needle which can cause hydrolock you may be experiencing. Because the new needles may eventually fail as well I'd install an inline shutoff valve about four to five inches from the carb, it's fairly easy to get too just above the horizontal cylinder head. Just decide where it fits best for you when you are installing the new fuel line. I'm almost positive that any original fuel line must be hard as a rock and just about wasted. That Y fitting is probably very brittle as well, I'd replace. Let us know how she's doin.
I to have a 92 750ss with the same starting problems as you have described.It appears as everyone has said that the the motor does have a hydrostatic lock due to excessive fuel in the cylinders.I have gone to shutting off my fuel tap if the bike will be sitting for awhile,especially in colder weather.What amazes me is that I also found a similar screw when draining my oil,about 10,000 miles ago. I've done 2 track days since without problems,go figure.
I should have mentioned this before but the reason I mentioned putting another fuel valve before the carbs is because even when you close the undertank valve the contents of the return line can go back through the y fitting after the valve and into the cylinders. Still closing the valve under the tamk is better than nothing because I believe the return line can only dump so much fuel as its return end is situated high in the tank.
Still closing the valve under the tamk is better than nothing because I believe the return line can only dump so much fuel as its return end is situated high in the tank.
Sideways (or anyone so inclined), do you mind taking a minute to briefly explain what's going on w.hydrolocking? I'm not sure I understand what's happening.
I to have a 92 750ss with the same starting problems as you have described.It appears as everyone has said that the the motor does have a hydrostatic lock due to excessive fuel in the cylinders.I have gone to shutting off my fuel tap if the bike will be sitting for awhile,especially in colder weather.What amazes me is that I also found a similar screw when draining my oil,about 10,000 miles ago. I've done 2 track days since without problems,go figure.
Thanks for your reply Boxer - makes me feel a little better that I'm not the only one around here so afflicted
Anyway, since being advised to do so I've been shutting the undertank screw but it's still happened. Though probably less than otherwise. Guess that's where Sidways' note about the Y-split remnants come in...
hydrostatic lock is when fuel is running into the cylinder past the float valve needles fills up the cylinder. liquid being uncompressable, the piston cannot move the fuel out of the cylinder on the compression stroke when both valves are closed. This is what makes everything stop like the motor is locked up. The fuel either has go out through the exhaust valve or past the rings into the crankcases.
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