massive oil leak instant gasket needed

[smiffyraf1]

came home after a month or so away to find the ss (not the monster luckily) had dumped all its oil over the garage floor. the leak appears to be alternator case side so was going to split it apart, clean and reseal. only problem is ducati don't make gaskets anymore for these. have been told loctite 851 is the best thing to use but as i cant find any in the uk was wondering if anyone can recommend anything else half decent.

[jerry]

I used well seal or yamabond you may have to reset the ecu pickup senders as gasket goo is thinner than the paper gasket ,,, its trial and error

[Trent]

Ducati use ThreeBond - the non branded ThreeBond is cheaper than the Ducati branded stuff.
I would imagine YamaBond is the same thing... but branded for Yamaha.

http://www.ebay.co.uk/itm/Genuine-Ducati-Spare-Parts-Threebond-Liquid-Gasket-50G-748-916-996-749-1098-/170996811972?pt=UK_Motorcycle_Parts&hash=item27d03448c4

http://www.ebay.co.uk/itm/THREEBOND-GASKET-CEMENT-SEALER-1-TUBE-/360491845943?pt=UK_Motorcycle_Parts&hash=item53eefd0937

[smiffyraf1]

thanks for that! ordered

[utopia]

My yr2000 m750 didn't have a gasket on that casing anyway.
Maybe the earlier ones did...I dunno.
The threebond stuff may do the job, but if you wanted a paper gasket you could probably buy some gasket material of the required thickness and cut your own gasket using the casing as a template.
A punch for the bolt holes can be easily made by sharpening the end of a suitably sized piece of metal tube.
I've done this many times, though not for this particular casing.

[smiffyraf1]

yeah that sounds far too much like hard work. well im hoping it is that case cant see where else it would come from

[Dookbob]

I used well seal or yamabond you may have to reset the ecu pickup senders as gasket goo is thinner than the paper gasket ,,, its trial and error

The pick ups should not need to be touched

[smiffyraf1]

its too bloody cold to even try and work in the garage today will have a crack when the weathes better from what i can see is coming from the front of the left side case. obviously compounded by being on the side stand. gonna give the case a good strip and paint while its off anyway as its looking a bit tatty. bit gutted as was going to be putting it up for sale anyway today. suppose its fate as people wont be looking with this weather!

[Mr Gremlin]

classic gaskets stock all the old air cooled ducati gaskets. their details are on here somewhere. a search should find them :)

[jerry]

The pick ups should not need to be touched


agree.....but sometimes they do its rare though .

[Sirc]

its too bloody cold to even try and work in the garage today will have a crack when the weathes better from what i can see is coming from the front of the left side case.
If you are certain leak eminates from cover joint something you could 'cross off the list' even in this cold weather - armed with allen key, just go around the periphery of the case checking for tightness obviously starting with the lower fixings. You never know your luck. (just a long shot - have you got any previous acid dribble witness signs around the area of the leak?)

[smiffyraf1]

its had a bit of a leak for a year that gradually got worse despite tweaking of bolts, didnt want to over tighten as they are SS and didnt want to strip the thread on the casing

[smiffyraf1]

right had a shock tonight, removed the alternator case and was like removing the finger from the dyke but not oil came out but fuel. the whole engine seems full of it. checked the carb and the float seems fine just about to take the lower cylinder rocker cover off to see if its there too but how the hell has this happened? the daft thing is i started it before removing the case just to make sure it ran before i removed everything and it ran fine!

[Dookbob]

Are your carbs the standard Mikunis, or the FCR type?

[smiffyraf1]

standard mikunis. have just started ripping them apart to check the needles, only seems to be the horizontal cylinder which would suggest floats but am baffled they all seem fine. noticed id left the choke on but cant see that affecting it, already bought an inline fuel tap on ebay tonight to stop this happening again.

[Dookbob]

The vac operated fuel tap is obviously passing, I have never been a fan of these type of taps, they are ok when the bike is newish, but you don't get any warning when they are going to fail. I would do the same as you are going to do, fit a manual tap.

[utopia]

I'm also wary of the vacuum fuel taps, but so far mine has been ok for 12yrs.
......at least, I think it has. I'm assuming that fuel can only leak through to the motor if the float valve/s are also leaking.
I'm also not exactly sure why this type of tap is chosen in the first place. My best guesses are that either its a convenience thing, ie it saves having to bother switching the tap on/off each time, or that its some sort of protection for the vacuum pump so that its virtually impossible to run the pump against the resistance of a closed fuel supply.
If the latter, then there is obviously some hazard associated with fitting a manual tap which you might forget to switch on.
I'm also assuming that, as a pump is fitted in the first place, there is insufficient head of pressure from the tank to feed the carbs when the fuel level in the tank drops below a certain level....in which case I assume that its impossible for fuel to leak to the motor unless the tank contains more than this minimum level of fuel.
This seems like as good a time as any to ask whether anyone can confirm or refute any of the above logic.

Another downside of the vacuum tap is that, when I take my dommie out I'm forever forgetting to turn on the manual fuel tap, being used to the automatic supply from the monster's vacuum operated system. This can be mildly hazardous, depending on exactly when the motor starts to splutter as the fuel in the float bowl is exhausted. Or is that a downside of the manual tap ?

I remember that the carbs on my old 350 yamaha had overflow tubes in the float bowls....kinda like a stack pipe which would prevent the bowls filling beyond a certain height, slightly above the normal float valve controlled level.
I know this because one of these tubes became detatched on one occaision, leaving an open hole in the bottom of the float bowl, which dumped a steady stream of fuel out of the carb and almost directly on to the rear tyre, though the engine still ran reasonably well. This had an interesting affect on rear wheel grip.

[smiffyraf1]

yeah i see no harm fitting a manual tap if anything will be like a cheap immobiliser ;) i love the SS though even when it plays up and is bits. im not sure if the gearing is different to the monster or the fueling but having ridden them both and considering its the same engine the ss is a bloody beast. scared the bejeezus out of me the first time i rode it as i expected it to be a faired monster.

[jerry]

If the engine has been full of fuel might be worth doing an oil change once the fault is sorted

[Unit 18]

Sorry, I'm probably being a bit thick but the carb SS's came with a manual fuel tap located on the base of the tank, they don't have a vacuum tap as they use a fuel pump.

http://i.ebayimg.com/t/New-Genuine-Ducati-750-900-SS-Fuel-tap-petcock-valve-58840051A-Rubinetto-/00/s/MTIwMFgxNjAw/z/opgAAOxy~dBRH2ws/$T2eC16FHJHIE9nysd9oSBRH2ws(ks!~~60_12.JPG

[Sirc]

as said, still has to have a weeping needle valve in one of the two float chambers as these have 'the final say' when it comes to a fuel leak via an inlet manifold. Fairly common after storage and particularly with the current fuel here.

[smiffyraf1]

well just had a look all over to make sure i wasnt being a biff but no stop cock currently exists on the ss it does look like its been chopped about a bit in the past so not inconceivable it has been removed at some point. needles dont appear to be seeping anymore so wonder if this was just while it was sat and with the weight of a full tank of fuel on them

[utopia]

Are you saying that there's no fuel tap at all ?
I also note that you said the leak had been present for quite some time, which would tally with the above.
Worryingly, I guess that would mean your oil's been diluted with fuel for some time.
Either way, its time for new oil.

A further thought on the vac fuel tap (monster or other).
It sounds like if you should forget to turn off the manual tap and leave the bike standing with a fairly full tank, and your float valves were leaky, then fuel would seep to the crankcases.
This would be avoided by the automatic shut-off of the vac tap ...as long as it was working properly.
So maybe this is the reason for fitting the vac tap ....or part of it anyway.

I'm maybe starting to have a little more faith in the vac tap now.
And making a mental note to leave the tank empty over a winter lay-up, and also to overhaul or replace the tap every few years.

I've obviously not given anywhere near enough thought to the issue of fuel taps in the past. ;)
But maybe I now understand how the oil level in my TL125 suddenly rose dramatically .....in 1978.

[smiffyraf1]

No it has always had a bit of an oil leak but when the crank case filled full of fuel it poured out of the place where oil had previusly leaked obv with fuel being less viscous. Yep no tap at all that i can see. Manual anyway. Must have a vac tap. But yeah theres no oil left in there now its all been washed away! Looks clean though. Gonna have to fill turn the engine over a few times with plugs out, drain then refill

[Unit 18]

I did some work on a Monster last year that had sat for a couple of years and the fuel tank had emptied into the front cylinder, it lifted the plating from the barrel and the piston was seized in it.

https://fbcdn-sphotos-a-a.akamaihd.net/hphotos-ak-ash4/p480x480/385668_433676269984601_1497304671_n.jpg

https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-prn1/p480x480/401664_434916543193907_347794559_n.jpg

[smiffyraf1]

crikey. well mine hasnt sat that long and the piston luckily must be ok as i ran it before stripping it

[utopia]

Eeek....mixture does look a tad rich on the horizontal cylinder !!!!

Damn...thats another thing to worry about, and my paranoia level was just dropping nicely, having finally managed to squeeze a case-saver in the very limited space around my gearbox sprocket.

Smiffy...you say "there must be a vac tap", but if the bike's been fiddled with by previous owners then I'm wondering if they may have removed the tap completely.....unlikely perhaps, but possible.
Also, though you thought the earlier leaks were oil, could they have been fuel-assisted too ? It does seem a bit of a suspicious coincidence that the leak was from the same point, like the two events were possibly linked by the fuel leakage, rather than by the failure of the case seal.
If there is no tap fitted at all, then this would be a likely possibility, as only the float valves would have been sealing the fuel lines for years.

[smiffyraf1]

nah as with pipe off carb nowt is coming out now. yeah previous leak was definitely just oil. was usualy only a spot every now and then and as have been told there isnt any gasket or anything on the case just polished mating face so not water tight

[Unit 18]

Don't worry too much, it had been sitting for at least a couple of years, the carbs were completley seized as well!

[Sirc]

scratching my head here Utopia - you have an M750 - does yours have a fuel tap? my M900 doesn't - maybe I am missing something here.. equivalent year SS has a thimble screw on the underside of the fuel tank but nothing on Monster

[utopia]

Yep, my m750 has a vacuum operated fuel tap.
I'm guessing your 900 has one too, if it doesn't have the manual tap.

[Sirc]

now I get it - a difference in naming terms. I would never have called that a tap - and will be interested to see what the Italian part listing says just out of interest.

[crust]

Some M900s had a manual tap, some didn't.

It is on the RH side just below the seat/tank.

[utopia]

Actually, my ducati workshop manual refers to it as a "vacuum-operated cock", but I thought that sounded a bit too "James May".
Haynes manual seems to make no mention of it at all, implying by omission that all models have the "manual-operated cock" .......there, I've said it now.
I'm guessing that Haynes saw that one coming (no, stoppit) and so they called that a "tap".

[Sirc]

yes.. ^ :) - more a 'fuel supply isolator' really and possibly a good safety measure in the event of an accident.