Ugh...... rapid onset oil/gas leak

[robtattoo]

I'm thinking my carbs are overflowing, running through the inlet valve & leaking into the sump
I noticed a gassy-oily puddle a couple of weeks ago (she's been stood for a few weeks) and last Saturday decided to go for a ride, see if I could blow off the cobwebs. She started up fine enough, but idle was a lot lower than it normally is. I put that down to inactivity & the cold. I managed 2½ miles before she started to sputter. I kept her running & turned round, got home & as soon as I pulled the clutch to stop, she died on me. Left a pretty hefty oil trail leading into the car port.

I haven't had the chance or motivation to do anything since, but I'm really, really hoping I haven't blown the crank or output shaft seal!
I'm actually dreading starting the diagnosis.....

 

[Jan_P]

Dip stick level ?
Oil glass ?
Can it be seen where the oil exits
Any rattle ?
Please check charging voltage across battery

 

[gggGary]

With you, hoping for the best.
Check the dip stick?
Drain the sump and see what you got.
I had one set of leaky carbs, petcocks that filled a crank three times, Each time thought I had fixed it but.........nope, grrr
And what do you do with a couple gallons of 50/50 oil n gas?

 

[mrtwowheel]

And what do you do with a couple gallons of 50/50 oil n gas?

Bonfire starter?

 

[toglhot]

Always use inline filters and always turn the petcocks off when not running. Vacuum petcocks s are a pretty good mod.

 

[robtattoo]

I honestly haven't even looked beyond checking the dipstick. That seemed OK, but i guess gas floating in the oil is going to be tough to see. Glass looks full. I'm not sure it was when parked. I'm pretty sure it was only at the upper level line.

I can't see obviously where the leak is coming from but again, I haven't really looked yet. I think (I'm hoping) it may be the airbox. There are drops directly under the alternator casing that could've run there, but I'm already in crank-seal-panic & i don't wanna think about that (and you can't make me!)

It's an '81, so the vacuum petcocks may also need a quick looking at.

 

[gggGary]

Sniff your stick.

you'll smell gas if it's in there.

 

[Adamc]

With you, hoping for the best.
Check the dip stick?
Drain the sump and see what you got.
I had one set of leaky carbs, petcocks that filled a crank three times, Each time thought I had fixed it but.........nope, grrr
And what do you do with a couple gallons of 50/50 oil n gas?

Similar problem with my Welsh Tracker. Stupidly left the petcock on 'Res' overnight, whilst on side stand. Petrol seeped through into sump and left a pet/oil mess on the floor in the morning. Drained and flushed the crank case and refilled with suitable oil. Didn't leave the petcock on at all since.... OFF OFF OFF is the mantra.

 

[toglhot]

I honestly haven't even looked beyond checking the dipstick. That seemed OK, but i guess gas floating in the oil is going to be tough to see. Glass looks full. I'm not sure it was when parked. I'm pretty sure it was only at the upper level line.

I can't see obviously where the leak is coming from but again, I haven't really looked yet. I think (I'm hoping) it may be the airbox. There are drops directly under the alternator casing that could've run there, but I'm already in crank-seal-panic & i don't wanna think about that (and you can't make me!)

It's an '81, so the vacuum petcocks may also need a quick looking at.

Petrol doesn't float in the oil, it mixes with it making the oil thinner and loses it's viscosity. If in doubt, dump the oil and replace. Almost certainly you float needle is not sealing properly. Always use an online filter, no matter how fastidious you are in cleaning your tank, some rubbish will always dislodge and deposit itself between needle and seat. Leaking fuel can come out the vent pipes or up through the slide needle, some will find its way back to the air filter or into the sump.

 

[robtattoo]

I need a bigger oil drain pan.....

At least I know how much gas the engine holds.....
The tank was full when I parked her up. It was empty when I took it off.

I cleaned & rebuilt the petcock & carbs & everything is as it should be, but I need inlet manifold gaskets before I can fire her up again.

 

[Wingedwheel]

That’s gonna leave a mark!

 

[jetmechmarty]

Did you use a K&L kit to rebuild the vacuum petcock?

https://www.xs650.com/threads/vacuum-petcock-rebuild-kit-fail.65527/

Also, one or both of your carburetor float valves failed to seal.

 

[2BallCane]

My vacuum petcocks lea leaked when I got mine, so I switched over to manual to make sure that didn’t happen again. always shut off your petcock when you park

 

[jetmechmarty]

My vacuum petcocks lea leaked when I got mine, so I switched over to manual to make sure that didn’t happen again. always shut off your petcock when you park

I did that too. Rebuilt the manual petcock. It worked for 3K miles. Now, it leaks. It’s an aftermarket POS.

At least it leaks onto the engine switched on, rather than into the engine switched off. I have only to be concerned about going down the road on fire.

 

[robtattoo]

Did you use a K&L kit to rebuild the vacuum petcock?

https://www.xs650.com/threads/vacuum-petcock-rebuild-kit-fail.65527/

Also, one or both of your carburetor float valves failed to seal.

I didn't. I screwed up & ordered one from Mike's. Completely the wrong part, however the round, 4-hole seal was the same, as were a couple of the others & I changed those out.
The diaphragm is completely different, but I checked out my old one, reinstalled it & tested it with a quick suck & it shuts down perfectly.
Right now there's no leak from the tap, but I'm giving serious thought to swapping it out for a manual.

I stripped, cleaned & rebuilt the carbs. There was a BUNCH of junk in the bottom of the bowls. They're sealing up & shutting off great as well, now.
I did forget (it's been a looooooong time.....) that I had to remove the inlet rubbers to get the carbs out & didn't think to order any new gaskets, so I can't test it out properly yet, but I'm fervently hoping that was the extent of the issue & I didn't do any serious damage by running it.

 

[jetmechmarty]

Right now there's no leak from the tap, but I'm giving serious thought to swapping it out for a manual.

IMHO, the quality of the aftermarket manual petcock is marginal. It may not be the perfect solution. My '81 650 is down for a leaking manual petcock. It worked perfectly for almost 3,000 miles. It was a PITA to set it up properly in the first place.

 

[robtattoo]

Well.......spit.

 

[robtattoo]

Well, the petcock is still leaking a tiny amount.
I attached a piece of clear, ¼" tubing with one end blocked off & it dribbled out 2" over the week & the vacuum shutoff passed the "give it a quick suck" test. That'll do for now.
I stuck the carbs to the tank with the tap on prime & left them sitting for an hour & no leaks at all.

Bolted it all together, primed the carbs, crossed my fingies & pushed the button. Aaaaaaand she runs perfectly. I left it idling for 20 minutes on a clean sheet of cardboard, no drips, & went for a couple of mile blast. Still no oil leaks anywhere.
I really was concerned about the crank, pushrod & output shaft seals, but it seems I dodged a bullet!