Petcock leak NO MORE

[feelergaugephil]

I have posted this a few times, so here goes again.....

Tired of the petcock leaking into the carbs/airbox/crank, easy fix for $3.00.
Go buy a in line fuel cut off switch, My GS1000 leaked, so I bought the petcock rebuild kit, what a waste of $$ that was, so I installed the cut off switch, never had a issue yet, been installed 3 years now, all I do when I have finished riding the GS, is turn the switch off, it doesn't leak EVER...

 

[Nessism]

This kind of repair sounds like a cheap getto repair - good to get you home if you are away on a trip or something. Unfortunately, adding a fuel cut off like you suggest is sidestepping the root cause of problem so I don't recommend this kind of repair as a long term fix.

Carbs overflow because the float needles are not holding back the fuel. If your float heights are set properly, and the needles and seats are in good working order, gas should not overflow out of the carbs even if the petcock is flowing all the time - such as it will if left on the Prime position.

If the petcock has failed and will not stop the flow of fuel when the vacuum source is removed, you are further at risk of fuel flowing backwards down the vacuum line and back into the engine. The proper long term fix is to replace the petcock.

 

[jed.only]

why dont you just turn the petcock off for FREE?

 

[tkent02]

why dont you just turn the petcock off for FREE?

Because it doesn't have an OFF position.

 

[feelergaugephil]

OK here's the deal, if your petcock leaks overnight, which they do give out on occasions, if you try to crank it with a crank case full of gas, GUESS WHAT! your buying a new or another crank, cos you just bent the conrods on 1-4 or 2-3.
I swear by them, cos the GS pet cock is useless........

Happy rider of a GS for 23 years................

Oh. and many years ago, I bent 1-4 conrod because the petcock failed.

 

[burp reynolds]

This kind of repair sounds like a cheap getto repair -

You're right, but it's the one I'm settling for until I find a source for new needles and seats...speaking of, where would you go for seats? I've seen needles a-plenty, but never any seats. And I'm not buying a whole four pack of rebuild kits.

 

[Nessism]

Not much cheaper than the entire kit... http://z1enterprises.com/detail.aspx?ID=2556

 

[burp reynolds]

Not much cheaper than the entire kit... http://z1enterprises.com/detail.aspx?ID=2556

13.30 X 4. For a bike with 60,000 miles. Unreal. I always ask myself, "W.W.T.D.I.A.F.F.S?" Or, "What Would They Do In Africa, For F***'s Sake?" So, there has to be some kind of hack that the ultra-remote desperate mechanic used when the nearest parts store was 2000Km away and the internet was merely the plaything of MIT students and The Wheelchair Guy. What was that hack?

If one were to mount a sacrificial needle into a drill and spin the tip around in the valve seats, one would run the risk of galling the seats, our would one? Perhaps the hardness of the needle and the softness of the seat would suspend galling, at least at first. What if one were to fashion a 'driver' for the needle out of a thin tube with an inner diameter just larger than the spring loaded rod at the back of the needle? And what if one were to use that driver and a very light hammer to gently seat the needle into the seat?

Oh, I'm mad, am I? ...Or am I the sanest man you've ever met?!!!

 

[tkent02]

If one were to mount a sacrificial needle into a drill and spin the tip around in the valve seats, one would run the risk of galling the seats, our would one? Perhaps the hardness of the needle and the softness of the seat would suspend galling, at least at first.

Use lapping compound, no galling. Spin the needle into the seat, like an intake valve.
It works sometimes.

I swear by them, cos the GS pet cock is useless........

They have worked fine for me for thirty years now on untold numbers of Suzukis.
If you are worried about the crank thing put an overflow in the float bowls like the pre EPA bikes had, so the gas can go someplace besides the crankcase.
Easy stuff.

 

[silverhorse47]

I don't think this is a "cheap ghetto repair" at all. If the needle valves in the carbies were meant to completely hold back the gas, why is there a petcock at all? And I think all bikes have a petcock.
If the diaphragm is leaking and not holding the gas back, what is wrong with an inline valve to shut off the gas? It serves exactly the same purpose as the diaphragm, is mechanical and not liable to failure, and is easy to install without dismantling the tank or carbs.
IMO there is nothing wrong with this type of sensible repair for an elderly machine. In fact, I think it is good mechanics, especially if the inline valve is of good quality and is capably installed.
It's kind of silly to insult realistic and affordable solutions to common problems on a forum for motorcycle repair.
S.

 

[feelergaugephil]

I don't think this is a "cheap ghetto repair" at all. If the needle valves in the carbies were meant to completely hold back the gas, why is there a petcock at all? And I think all bikes have a petcock.
If the diaphragm is leaking and not holding the gas back, what is wrong with an inline valve to shut off the gas? It serves exactly the same purpose as the diaphragm, is mechanical and not liable to failure, and is easy to install without dismantling the tank or carbs.
IMO there is nothing wrong with this type of sensible repair for an elderly machine. In fact, I think it is good mechanics, especially if the inline valve is of good quality and is capably installed.
It's kind of silly to insult realistic and affordable solutions to common problems on a forum for motorcycle repair.
S.

Ah! someone in agreement........ We used to use them on the older cars we had, and have it on the gas line under the drivers side, if someone stole the car, it would go maybe 2 blocks and then cut out......... and the thief would have no clue whats wrong with the car he just stole!

 

[argonsagas]

"cheap ghetto repairs"?

Sorry, but I fail to see anything wrong with simple solutions to surmountable problems.

Let's see.... just a few.....

The Bandit has a large staple taped in place between the wire ends on the clutch switch which failed, and the local Suzuki dealer could not find a replacement.

When the throttle cable failed on my year-old Celica I used bicycle cable .....$3 instead of $45. It performed flawlessly for the 7 years that I had the car.

My 1100G ignition switch sports a BB as a bearing, because on original bearing was lost.

The GK windshield is Lexan....cut and fitted in my garage.

Bent Guzzi crash bars were formed from stainless tubing and welded to the original plates after the originals had done their job in a crash.

The Guzzi clutch cable was fabricated from galvanized aircraft cable.



And the one that allows me to talk to you today:


Early 60's model cars came with no seat belts.....I bought aircraft lap belts, drilled the floors and installed them, using reinforcing plates.

When a large Chevy drove into us head-on, and the Mini-minor folded, pushing the steering wheel upwards against the roof, the belt held me in place, instead of being crushed to a certain death between them, and the friend who was with me was kept from going through the windshield, although his head did bump against it.



If any simple repair works, and especially if it works well, is there really anything more that you should reasonably ask of it?



.

 

[Nessism]

If your float needles are leaking to the point where gas is winding up on the floor, or in the crankcase when the bike is parked, you can be assured that the fuel level in the carbs will be too high for proper running while you are on the road. Time to fix the float needle problem if you care about feeding your engine the proper mixture.

Getting back to the petcock, if budget forces a fuel shutoff repair like the one proposed by Phil, make sure you remove the vacuum line and plug both ends. One of the classic failure modes for these petcocks is for fuel to flow backwards down the vacuum line and into the engine. If the petcock won't shut off the fuel flow it very likely could start leaking internally very soon; basically the petcock is a ticking time bomb waiting to dump fuel directly into the engine. Again I say, adding this fuel shutoff valve is not addressing the root cause of the problem but hey, do what you want.

 

[jwhelan65]

Agreed

Agreed

I have to agree with Nessism, I had this same issue with my 1100. I had a mechanic talk me into adding a cheap shut off valve. It worked for awhile but I ended up replacing the petcock. Certainly a shut off valve is effective, but honestly its like trying to stop internal bleeding with a band-aid. If your carbs and petcock are fuctioning properly this would not be necessary.

 

[hampshirehog]

I tend to agree with both sides (nothing like sitting on the fence). Yes, the float valves should be sorted. Often just a bl**dy good clean up and a spin between your finger / thumb is enough to seat them nicely again.

But the Suzuki petcocks are pretty cr*ppy as well and having an extra tap in line gives a bit of extra comfort.

And Ed is bang on about fuel finding its way down the vacuum tube. I've just had to sort this out on a mate's CBR600 though fortunately the fuel was only being pulled down when the motor was spinning. In this case it was squirting out of the pipe where it met the intake as the pipe wasn't a real tight fit and petrol was pouring over his motor - he's a real lucky boy it didn't burst into flames. Replacement diaphragm was expensive too - just under ?40.

 

[silverhorse47]

If your float needles are leaking to the point where gas is winding up on the floor, or in the crankcase when the bike is parked, you can be assured that the fuel level in the carbs will be too high for proper running while you are on the road.



->This is not necessarily true. The needle/float combination is designed to allow fuel to flow into the float bowl when it drops to a certain level, and stop it flowing when it rises to a certain level. When the engine is running they can do this very well and still be a bit leaky, and performance will not necessarily be affected. They are opening and closing all the time anyway. A bit of leaking when they are closed isn't likely to change float level significantly in a running engine unless there is a really grave condition.

The petcock on the other hand is designed to shut off the gas supply to the bike when the engine is not running.

These are two separate functions, and it isn't entirely correct to expect the float needles, which are designed to regulate fuel level, to also perform the job of the petcock, which is designed to completely stop gas from reaching the carbs.

I think most of us would agree that in an ideal world we would go to the store and buy the right part and install it using the methods in the factory service manual. However in real life, after a decade or four of doing that, one develops a sense of what is good mechanical practice and what is not, and we make these decisions for ourselves, and when we find something that works, we sometimes pass it on. That's what makes the forum so great.

The point I was really trying to make is that it perhaps doesn't help the forum if we use words like 'cheap' or 'ghetto', or any other pejorative to describe repair suggestions. This particular one is widely accepted...even preferred... by some very fastidious mechanics. Most of us know that it's good if everything is perfect and factory and expensive all the time. However, the fact is that everything rarely is perfect all the time. Sometimes the float needles do not seal for one reason or another.

At that point, a diaphragm petcock, which is designed to stop all flow of gas to the carbs, may fail to protect your engine from hydrolock. A mechanical inline petcock is fail safe. Why knock it?

S.

 

[feelergaugephil]

Yes the big word is HYDROLOCK........................

For those of you that have never experienced that, or even the loud crack noise that comes with it, it's VERY EXPENSIVE.
I was not trying to skimp out on $$$$ to cut corners, I have approx $6-$7K in this bike so why would I cut corners.......
And by the way! completely rebuilt carbs (ALL NEW STUFF) including diaphrams, and NEW petcock internals, after 3 weeks the petcock gave out, I could smell the gas in the garage, so I instantly dropped the oil, and took the spark plugs out and turned her over, no issues.
So, to stop all the hassles, an inline stop switch was put on the main line.

Call it a ghetto repair or anything else, it does its job and will NEVER leak and I will never again get a HYDROLOCK.

I had a GS1000 years ago which did hydrolock, when I stripped it down I bend 2 of the conrods, when I spoke to the dealer he advised "yeah! common problem with those GS's leaking, rebuild the motor and put an inline fuel stop on it"

I put this inline stop in for 100% safety as I don't want to spend more money on my engine which I probably have $3K in it.

 

[Zook]

All my bikes have a Briggs & Stratton inline fuel shutoff. Cost all of $3.50 at the hardware store.
Funny....Suzukis and Kaw Concours have something in common...lousy petcocks and carb seats and needles.
On the Connies it's not a matter of IF you will hydrolock the engine it is WHEN.
On those the petcock rebuild kits are worthless and the carb seats are NOT replaceable.

Soooo...gut the petcock, block off the vacuum fittings and install the B&S valve. Problem solved.
IMO the vacuum operated petcocks were ment to mask the bad carbs until later...then you spend lots of $ if you bend a rod. And you still spend a lot to replace petcocks and needles.

It's also odd...every Guzzi I've ever owned had manual petcocks and dell'orto crbs...NEVER had a needle and seat leak fuel. I never worry about not shutting off the fuel, although I make it a habit to do so.

A check on the COG board will see LOTS of threads on this subject, while on the Guzzi board....nothing.

The GS I bought last fall had about 2-1/2 to 3 GALLONS of fuel in the engine....I didn't think it could hold that much!

 

[tlg1100]

my petcock leak thru vacuum hose flooding #2 cyl. diaphragm had pin hole in it.put a piece of gasket in place of rubber diaphragm and rode a few weeks like that until new one came in.put the new one in and it went bad in a month. have new one ordered at 75 bucks.the carbs did stop fuel from getting in motor with fuel going to carbs all the time.i put in briggs shut off to be safe this time.was thinking about shut off valve from j@p cycle easier to move position from on and off. had friend do damage from hydro lock hate to chance it.

 

[49er]

K & L kits rule

K & L kits rule

I'm surprised Bwringer hasn't weighed in on this one. I agree with his past philosophy on this matter. Buy a new stock petcock and forget about it for another 20 years of operation. You won't need to remember to turn off a manual valve, ever!!

Nessism is right. Decent needle valve assys shouldn't leak. Dellorto and Weber needles, to name a couple, will hold back up to 4 psi of fuel pressure, before flooding and engine at idle. There's no way that our gravity feed lines are running anywhere near that pressure. Decent needle valves and correctly set float heights shouldn't require a manual shut off valve. It is very convenient to have a valve or petcock, when it comes to removing your tank though! If you are in the habit of using the side stand, you do need to be precise with your float levels too.

When I rebuilt my VM carbs, I bought K & L carb rebuild kits. I only used the new bowl gaskets, needle valve assys and the o rings, out of the kits. I decided to reuse the original suzuki pilot air and pilot fuel screws as their tapers were marginally finer at the point than the replacements. Some say that this is an advantage, but I think that Suzuki went to these lengths to guarantee a very lean pilot circuit. Too lean, IMO.

Because of the quality of these carb kits, I decided to buy a K & L petcock rebuild kit. All the seals and diaphragms were precisely made and it has functioned well for the last month. My petcock did not fail, but after its last inspection, I knew that its days were numbered. Prevention is better than cure.

I know the general consensus has been not to bother with rebuild kits, but if the quality is there, why not? I'm sure that many of the kits out there are crap, but I'm just passing on my experience with this particular manufacturer.