Gas smell in oil???

[gsvol]

I have put new jets in and cleaned carbs and put on a new OEM petcock..bike runs super starts and run when cold no choke

but i still have a SLIGHT gas smell in oil

[hikermikem]

Do you leave the petcock on PRI (prime)?

[bccap]

Do not run it !! Until you figure out what's up. The petcock is the usual suspect. Is the oil over the sight glass ? Drain a little and check it. Did you leave it on prime ? Oil changes are cheaper than new engines.
If you do have oil in your gas and you address the issue and repair it. Put in fresh oil run it for fifty or so miles. Then do another oil change and change the filter as well this time.

[gsvol]

Do you leave the petcock on PRI (prime)?

dont know

its the 1980 petcock with no knob

i will pull hose off and see if gas runs free

[GSXR7ED]

Fuel Petcock

I have put new jets in and cleaned carbs and put on a new OEM petcock..bike runs super starts and run when cold no choke

but i still have a SLIGHT gas smell in oil

I checked 1980 model airboxes across the board and they all have drain tubes. This is important because if fuel leaked from the petcock to the carbs, (via the vacuum hose) it can drain out the exit tube.

NOTE: Is your vacuum hose clear? (see-through) If so, you'd be able to see fuel going into the carbs.

Of course, the fuel travel depends on if the bike was on the sidestand or the center stand. And also the angle of the carbs facing the engine.

dont know

its the 1980 petcock with no knob

i will pull hose off and see if gas runs free

[You didn't mention what type of bike you have and so I found the GS550 petcock with no knob]

Follow the steps as suggested if your oil level is above the limit line.


Ed

[gsvol]

I checked 1980 model airboxes across the board and they all have drain tubes. This is important because if fuel leaked from the petcock to the carbs, (via the vacuum hose) it can drain out the exit tube.

NOTE: Is your vacuum hose clear? (see-through) If so, you'd be able to see fuel going into the carbs.

Of course, the fuel travel depends on if the bike was on the sidestand or the center stand. And also the angle of the carbs facing the engine.



[You didn't mention what type of bike you have and so I found the GS550 petcock with no knob]

Follow the steps as suggested if your oil level is above the limit line.


Ed

no its not a clear tube

its on its center stand

its a 1980 GS750L

oil is not above full line

[Agemax]

no its not a clear tube

its on its center stand

its a 1980 GS750L

oil is not above full line

just ride it, but keep an eye on things

[GSXR7ED]

AirBox

no its not a clear tube

its on its center stand

its a 1980 GS750L

oil is not above full line

Alright...I've still got the parts site open and see your airbox looks similar to mine. If fuel leaks towards the airbox, there's a reservoir and drain tube behind the clutch gearbox. It happened to me and I was wondering why fuel was leaking under the engine.

So, how are you smelling fuel in the oil? Is it seaping from the heads?


Ed

[gsvol]

Alright...I've still got the parts site open and see your airbox looks similar to mine. If fuel leaks towards the airbox, there's a reservoir and drain tube behind the clutch gearbox. It happened to me and I was wondering why fuel was leaking under the engine.

So, how are you smelling fuel in the oil? Is it seaping from the heads?


Ed

i drained a little oil into a cup

no gas leaks under bike

[Steve]

its the 1980 petcock with no knob

i will pull hose off and see if gas runs free

The PRIme function on the (dreaded) '80 petocock works a bit differently than the rest of them

To activate fuel flow in PRIme, you have to first apply a 'puff' of vacuum, then it will free-flow, even though the vacuum is removed.

On any other petcock, you simply turn the lever to PRIme and fuel flows (assuming it's working properly).

In the RUN position, it works like all the rest. Apply vacuum, fuel flows. Remove vacuum, fuel stops.

I can't remember which slot position is which, though, as I don't have one of them, even though two of our bikes are '80 models. Thankfully, the non-"L" shafties were spared.

.

[GSXR7ED]

Oh man!

i drained a little oil into a cup

Something might be up with your carbs...possibly. You should replace the vacuum line with a clear hose...this way you'll see if the petcock is draining too much fuel into chamber #3.

I'd be concerned because my fear would be a fire starting between my legs if too much fuel is leaking. I don't mean to scare you but I was thinking about that when I saw how much fuel was in my "T's" reservoir. I may be overreacting to that but if it's on my mind, I won't feel comfortable riding my "T".

So the problem lies with either your carbs or the fuel petcock.


Ed

[gsvol]

The PRIme function on the (dreaded) '80 petocock works a bit differently than the rest of them

To activate fuel flow in PRIme, you have to first apply a 'puff' of vacuum, then it will free-flow, even though the vacuum is removed.

On any other petcock, you simply turn the lever to PRIme and fuel flows (assuming it's working properly).

In the RUN position, it works like all the rest. Apply vacuum, fuel flows. Remove vacuum, fuel stops.

I can't remember which slot position is which, though, as I don't have one of them, even though two of our bikes are '80 models. Thankfully, the non-"L" shafties were spared.

.

can i change PETCOCK to a diff one?

[gsvol]

Something might be up with your carbs...possibly. You should replace the vacuum line with a clear hose...this way you'll see if the petcock is draining too much fuel into chamber #3.

I'd be concerned because my fear would be a fire starting between my legs if too much fuel is leaking. I don't mean to scare you but I was thinking about that when I saw how much fuel was in my "T's" reservoir. I may be overreacting to that but if it's on my mind, I won't feel comfortable riding my "T".

So the problem lies with either your carbs or the fuel petcock.


Ed

the petcock is BRAN NEW!

and i have no gas leaks under bike

[Agemax]

the petcock is BRAN NEW!

and i have no gas leaks under bike

as i said before, just ride it but keep an eye on things. a slight whiff of gas is not uncommon. unless you see big puddles on the floor or your oil level rises rapidly i wouldn't worry about it.........

[GSXR7ED]

Trial & Error

the petcock is BRAN NEW!

and i have no gas leaks under bike

Yeah, it's brand new but there's no way to see if it's regulating fuel without the clear vacuum tube. So maybe it's the carbs??? You rebuilt them, right? I'm not saying you did a bad job but if the problem persists, I'd re-evaluate the carbs.

Follow Agemax's advice and just ride...eventually it should sort itself out/the fuel should burn through after several rides.

Didn't mean to get you riled up! I'm just offering possibilities from my recent experience with my fuel leak.

Ed