Kawasaki Concours Forum

The C10, aka Kawasaki Concours - The Original => The Bike - C10 => Topic started by: amigoride on May 27, 2013, 11:12:00 AM

Title: Petcock kit install
Post by: amigoride on May 27, 2013, 11:12:00 AM
I acquired a petcock rebuild kit and want to install it as a proactive measure. My 2005 Connie has never exhibited a problem related to the petcock but after almost 9 years it seems prudent to install new components. I know Steve's overflow tubes are the only real solution to potential hydrolock but the petcock kit seems a straight forward install. I have searched the topic and found a number of posts regarding poor results. Any tips on installing the kit? Should I even bother? Should I just order a new petcock from Murph?
Thanks guys, always a pleasure communicating. 
Title: Re: Petcock kit install
Post by: Strawboss on May 27, 2013, 11:15:33 AM
More than a few have installed the old fashioned manual type petcock kit. Something to look at if you are thinking of other options. Not sure of Murph sells them or not.
Title: Re: Petcock kit install
Post by: Outback_Jon on May 27, 2013, 12:15:07 PM
Murph has some recommendations on his site:  http://www.murphskits.com/catalog/product_info.php?cPath=1_94&products_id=121 (http://www.murphskits.com/catalog/product_info.php?cPath=1_94&products_id=121)

Murph does also sell a kit to convert the stock petcock to a manual one:  http://www.murphskits.com/catalog/product_info.php?cPath=1_94&products_id=483 (http://www.murphskits.com/catalog/product_info.php?cPath=1_94&products_id=483)
Title: Re: Petcock kit install
Post by: Nosmo on May 27, 2013, 09:12:53 PM
I rebuilt my OEM petcock several years ago using a K&L repair kit.  It leaked immediately because the parts in the K&L kit were bogus.  I found that the diameter of the center poppet and O-ring were too small to seal the central passage in the petcock.  I got fed up and installed a Pingel manual unit and am happy happy happy.  It has been reported by some here on the forum that the genuine Kawasaki kits are better than the aftermarket ones.  Be sure to inspect all the parts in the kit you got and if they are not identical in all respects you may have trouble.  Obviously you'll want to do a leak check before you install the unit or put fuel in the tank.
Title: Re: Petcock kit install
Post by: Easy13 on May 27, 2013, 11:10:53 PM
I installed Murph's manual petcock conversion kit this weekend.  Easy-peasy and no leaks.  Murph advertises Permatex aircraft-grade sealant and I went for that as well:  outstanding stuff!
Title: Re: Petcock kit install
Post by: Daytona_Mike on May 28, 2013, 09:08:58 AM
I hope you folks with manual petcocks have over flow tubes.  If not you are  much more likely to hydro-lock the engine than with the auto petcock
Title: Re: Petcock kit install
Post by: Cholla on May 28, 2013, 09:38:58 AM
I just installed a Briggs & Stratton lawnmower shutoff valve. Always works and cost $3.50.
Title: Re: Petcock kit install
Post by: Mettler1 on May 28, 2013, 10:23:57 AM
I just installed a Briggs & Stratton lawnmower shutoff valve. Always works and cost $3.50.

    Always???
Title: Re: Petcock kit install
Post by: Cholla on May 28, 2013, 10:44:00 AM
Yes, always.
Title: Re: Petcock kit install
Post by: T Cro ® on May 28, 2013, 01:30:54 PM
I hope you folks with manual petcocks have over flow tubes.  If not you are  much more likely to hydro-lock the engine than with the auto petcock

I'll continue to beg to argue that as false..... All one needs to do is turn on/off the tap; my job as a ship engineer requires that I follow precise procedures over and over again without fail or forgetting.

With that being said I believe that overflow tubes are worth far more than their cost as the human machine is subject to failure too.

As to rebuilding petcocks with factory parts yes... Rebuilding petcocks with K&L no way!
Title: Re: Petcock kit install
Post by: datsaxman@hotmail.com on May 28, 2013, 02:57:03 PM
I am with Tony on this one.  I NEVER forget to turn it off.  Just a matter of learning to do it.  I mean, do you forget to put your foot down when you stop?  Do you forget to put it in neutral before you let out the clutch at a stop?  Do you forget to get gas when the tank gets low? 

I am confident that the manual shutoff is OFF when it is turned off. 

Title: Re: Petcock kit install
Post by: jworth on May 28, 2013, 04:33:35 PM
The examples given above don't really help.  In each there is a very direct and immediate reaction for failing to do X or Y.  This is not the case with the fuel valve.  I suspect that each of you who "never" forgets to turn off their fuel valve have in fact done just that.  How can you even say for sure you didn't?  Maybe you just as easily forgot to turn it on.  What would have ever drawn it to your attention?  I still think that even subject to failure, the vacuum pet cock is more reliable than people, at the very least MOST people.  I certainly know myself well enough to know that (it) would be more reliable than me.  Maybe I speak for myself but that's just fine with me

*edited for typeo
Title: Re: Petcock kit install
Post by: datsaxman@hotmail.com on May 28, 2013, 06:44:30 PM
jworth...you said "...I would be more reliable than me."  OK.  I guess.

Okay, I agree with your immediate consequences point.  So how about this one:  Do you ever forget to take out the ignition key when you leave the bike?  That is comparable to the petcock question. 

Speak for yourself...I NEVER forget that, and I am trained to associate the key with the petcock.  Other folks do what they do, but I was speaking for myself alone right from the beginning. 

The same kind of debris that could cause the vacuum shutoff to leak could plug the overflow tubes.  Then hydrolock!  IT HAPPENED TO MY BIKE TWO MONTHS AGO!!   The (new) manual shutoff really shuts it off!  Oh, and I have the tubes too.  But they are less than 100% reliable, by actual experience. 
Title: Re: Petcock kit install
Post by: Outback_Jon on May 28, 2013, 07:52:45 PM
I mean, do you forget to put your foot down when you stop?  Do you forget to put it in neutral before you let out the clutch at a stop?  Do you forget to get gas when the tank gets low?
Well, you managed to hit on three reasons why I won't do the manual conversion.   ;D

Do you ever forget to take out the ignition key when you leave the bike?
Make that four reasons.   :rotflmao:
Title: Re: Petcock kit install
Post by: Daytona_Mike on May 28, 2013, 08:40:46 PM
Remembering to turn off the fuel is not the problem. Even IF you always remember turn off the fuel your worse off than an automatic petcock and here are the reasons.
 Automatic petcocks shut off the fuel flow the very instant the engine is no longer creating vacuum. That goes for starting the engine as well.
Humans  are  no where near as fast as automatics and certainly not every single time you stop the engine to say: add fuel to  the tank or when you open the petcock just before starting the engine. All these short instances of start-ups and shut downs   which occur many times during a single  ride has your  manual petcock  flowing  full wide open even if it is for a few seconds and  that is all it takes at full wide open and full pressure (plus a leaky float valve) to cause a hydro lock.That does not happen with an auto petcock even on  a failed auto petcock. The very worst failures on an automatic petcock is a slow dribble at low pressure.

So again if you have an automatic petcock make sure it is maintained. If you have a manual petcock and even IF you always turn it off and ON as fast as you can EVERY single stop AND  turning the fuel flow on before  the starting   of your  engine your  increasing your risk 10 fold over automatics.  It normally takes overnight with a dribbling Auto pet-cock to cause hydro-lock  but  it only take just a couple of seconds with a wide open full flowing manual pet cock.
JMHO.  Thanks
 

Title: Re: Petcock kit install
Post by: Daytona_Mike on May 28, 2013, 08:48:10 PM
The same kind of debris that could cause the vacuum shutoff to leak could plug the overflow tubes. 

If you have a chunk of debris large enough to choke shut an overflow tube  you have something seriously not right on your bike. I would say you have a hole in the tank screen which needs to be fixed.
Title: Re: Petcock kit install
Post by: T Cro ® on May 29, 2013, 07:50:05 AM
Automatic petcocks shut off the fuel flow the very instant the engine is no longer creating vacuum. That goes for starting the engine as well. Humans  are  no where near as fast as automatics...


Quite the fanciful bit of writing....
Title: Re: Petcock kit install
Post by: Cholla on May 29, 2013, 11:17:27 AM
It is proven the auto petcock is unreliable. Hence the proliferation of rebuild kits and manual replacements.
Besides the real problem is the poor design of the float valves.
Title: Re: Petcock kit install
Post by: datsaxman@hotmail.com on May 29, 2013, 11:47:59 AM
Appreciate the analysis, Daytona...yes, there was some damage.  Better now that the hydrolock prevention is not based on a flimsy screen.

You may be amused to learn that I turn off the petcock BEFORE I turn off the engine.  Faster than the automatic.  If I am not going to be riding for a while - we do get some Winter up here - I can run the fuel bowls dry if I like.  I like.  And yes, I turn on the fuel AFTER I start the engine.  Again, faster to anticipate than react.    I thought about the reaction time issue when I was fabricating a temporary solution by the side of the road 100 miles from home, and there is my response.

Thanks for the lively discussion...

Title: Re: Petcock kit install
Post by: Roadhound on May 29, 2013, 02:33:45 PM
I've been riding C-10s since 1990, a little over 23 years and a few 100,000 miles. I've had very few petcock problems. In every case the petcock would develop a slight external leak. I've never had one fail to the point where it would leak internally into the fuel line. I've rebuilt several including on friends bikes. The Kawasaki kit has worked well in every case where it was used, the K&L has not done as well in the few times we have tried it.
 
I don't do cars, I ride the bike for all of my transportation. The chance of me leaving the petcock turned on is great considering how often I ride and How often I'm on and off the bike.

I would not consider a manual petcock, as I feel the chance of me leaving the petcock turned on is far greater than the chance of the petcock failing. YMMV
Title: Re: Petcock kit install
Post by: GeeBeav on May 29, 2013, 08:24:51 PM

Quite the fanciful bit of writing....

Yes, quite . . .
Title: Re: Petcock kit install
Post by: Daytona_Mike on May 30, 2013, 06:50:08 AM
I guess so but the point is the same

datsaxman understands the risks with the manual. I would not have thought anyone else would. Good job datsaxman.
                   Just remember to do what your doing all the time even when the engine stalls say for example  a stuck open float valve  and your good to go unless you have over flow tubes then no worries.
Title: Re: Petcock kit install
Post by: Strawboss on May 30, 2013, 07:20:15 AM
I got a manual design. I'm pretty darn quick, but thanks for informing me that I'm not THAT quick. Dang! When can I expect this dreaded hydrolock you talk of?
Title: Re: Petcock kit install
Post by: T Cro ® on May 30, 2013, 07:29:25 AM
I got a manual design. I'm pretty darn quick, but thanks for informing me that I'm not THAT quick. Dang! When can I expect this dreaded hydrolock you talk of?

Your a hoseman your very job is accepting, expecting, mitigating and/or dealing with risk....
Title: Re: Petcock kit install
Post by: Cholla on May 30, 2013, 07:40:11 AM
Hydrolock will not happen while the engine is running because the fuel will be burned albeit not completely. It can't flow that much fuel that quickly.
But, let's say your petcock isn't shut off. The cylinders flood with fuel. What is the actual cause?
Poorly designed float valves. Since hydrolock is a common ocurrance there neleds to be a fix for the actual problem. Overflow tubes don't fix the problem. It just allows the fuel tank to empty onto the garge floor.
Title: Re: Petcock kit install
Post by: Strawboss on May 30, 2013, 08:09:13 AM
OK, not trying to be flippant or cause an uproar. I would think that if this problem is as bad as some say here concerning trashing motors, I would have thought that Kawasaki and all the other manufacturers that use this design, which has been around for decades, would have addressed this problem years ago. I mean, of all the bikes produced, other than anecdotal stories here on this forum, really, how many are experiencing this problem, how many are being ruined? Is there a study? Was there a memo? A recall? Please don't say they addressed it with the new C-14 as this design has been around for decades. Please don't tell me of your friends, family, racing buddies, mechanic's stories or a page long copy/paste treatise, these are all anectdotal. I would have thought that if this many motors were being damaged, that somebody somewhere in either marketing or engineering or design would have experienced it too and decided to redesign it or address it. Are there really THAT many motors being trashed? 
Title: Re: Petcock kit install
Post by: Cholla on May 30, 2013, 11:10:13 AM
It was fixed on the C14. It has fuel injection.
Title: Re: Petcock kit install
Post by: Strawboss on May 30, 2013, 12:03:12 PM
Nice try Cholla.
Title: Re: Petcock kit install
Post by: Cholla on May 30, 2013, 01:54:08 PM
Was there something that I stated that was incorrect?
They don't use the carbs on the C-14 so, it was addressed on the C-14.
Why should they worry? It doesn't happen until the bike is out of warranty. And HONDA makes the carbs.
Title: Re: Petcock kit install
Post by: jworth on May 30, 2013, 03:08:49 PM
@datsaxman
See reply 11 edited for typo
Title: Re: Petcock kit install
Post by: Strawboss on May 30, 2013, 04:55:03 PM
Read my post Cholla. All of it. Especially near the end where I mention the C-14.
Title: Re: Petcock kit install
Post by: Cholla on May 30, 2013, 05:49:13 PM
I know, you said to not say they addressed it on the C14 but, hey, ya gotta face it-they did address it and chucked the design.
I axed many moons ago why they continue to use the same carbs.
Title: Re: Petcock kit install
Post by: Strawboss on May 30, 2013, 06:15:54 PM
Oh ok. Anyhow, are we the only group of folks experiencing hydrolock, because I never heard of it until I came here I guess is what I'm saying.
Title: Re: Petcock kit install
Post by: Daytona_Mike on May 30, 2013, 07:18:49 PM
Strawboss.   You can thank the  US government for not wanting carburetors to vent fuel to the outside air.  Carburetors used to have overflow tubes to prevent this problem but the EPA said no. That is why the bowl castings still have bosses still there so it makes it easy for us to drill holes and add the tubes.

The problem is more frequent than those that post here with blown engines. Many owners have engines with  a bent connecting rod and do not know it. They may notice just a slight vibration and think it is normal. This is why we recommend doing a 'bent rod test' before buying any C10. Another so called ' fix' is to install a clutched starter that slips when it hits a heavy load such as a cylinder full of  fuel but that costs  significantly  more than over flow tubes.

Cholla.  It is not really  a flaw of the float needle seats. All it takes is a small or tiny bit of debris to cause a small float leak. We also dont notice that too often because it clears itself up while riding. Those of us who have over flow tubes  are aware right away when this happens and we just go for a spirited  occasional WOT ride and it clears up.

I should mention that I have had a lot of experience with problem  carbs early on. I had constant float needle issues due to very  tiny fine grains of sand getting into the carbs and landing in the bowls  due to the fact that I live next to the beach.(We have what is called Sugar Sand- it is extremely  fine). It was a big mystery as to why.  At one point I was sure I blew a hole in a piston because of the huge smoke cloud and it looked light blue. I even had a small sign on the handle bar that said "Tap the Starter lightly to make sure the engine is not locked"
 I tried every suggested method including: Inline filter(s), electric fuel shut of valve  and I even toyed with low pressure fuel pumps with filters.
Everything I tried induced other issues. It was not  until overflow tubes were suggested  (by Sunny Steve of course) and once I had those installed I was leaking fuel all over the place from all four carbs at different times. 
Turned out it was a split air box letting the sand in past the air filter.

Sorry for the long write up. I hope this helps.
Title: Re: Petcock kit install
Post by: Steve in Sunny Fla on May 30, 2013, 07:49:33 PM
Oh ok. Anyhow, are we the only group of folks experiencing hydrolock, because I never heard of it until I came here I guess is what I'm saying.

While I'm sure there's others, the ZRX guys are having trouble with hydrolock now. Common on their boards. Their engine layout is the same as ours. but they fortunately have a clutched starter gear that slips before bad stuff happens.

All - is hydrolock common? YES. If you watch my video on hydrolock, theres 3 engines represented there that hydro'ed. the first is the one the rod came from; the second is that 05 shortblock with the 2 bent rods; 3rd is the 01 that sprayed all over me. In the past year I've had an 87 in here with a bent rod, and an 86 with 2 bent rods. A couple years ago I swapped rods on an 03 that hydroe'd and locked up.

 roadhound rides day in, day out.  Changing the gas is probably the best thing for the bike's fuel system. the guys I know who ride everyday don't have many carb issues, but most motorcycles end up sitting because they're "pleasure craft" for most of us. And therein lies the problem. After having seen about  350 sets of carbs, I can tell you most bikes go through periods of inactivity, which doesn't do them any good.

 One more point - there's many many connies now fitted with overflow tubes, so those will be off the list for hydrolocks, unless something clogs the drain hose at the end(mud dauber?). As far as trash clogging the overflow tube in the carb? impossible. look at the height of the fuel valve, the depth of the bowl, and the height of the overflow tube. since large chunks of trash don't have legs to climb uphill, clogging the overflow tube itself just will not happen. .Steve
Title: Re: Petcock kit install
Post by: T Cro ® on May 30, 2013, 07:59:43 PM
While I'm sure there's others, the ZRX guys are having trouble with hydrolock now. Common on their boards. Their engine layout is the same as ours. but they fortunately have a clutched starter gear that slips before bad stuff happens. Steve

Steve, is the clutched starter something a Concours owner could fit to their engine?  Not going to run out and did it for hydro protection but it would be handy to know in the case of needing a replacement.
Title: Re: Petcock kit install
Post by: Strawboss on May 30, 2013, 08:06:32 PM
OK, thanks, that wasn't long at all, explained a few things. I remember I had a 1981 Kawasaki 305, 20,000 miles that leaked out a tube coming from the carbs, over flow or bowl drains? Who knows. Never had hydrolock though. My 1982 KZ, 52,000 miles occasionally leaks in the spring with the warmer/colder days combinations, no hydrolock. Go figure. I got the manual petcock, I'm not going to worry. As Tony said, like work, I do certain things the same way every single time, every time when I start and stop the motor. Clutched starter, so they did think about it then.
Title: Re: Petcock kit install
Post by: Steve in Sunny Fla on May 30, 2013, 08:07:54 PM
Steve, is the clutched starter something a Concours owner could fit to their engine?  Not going to run out and did it for hydro protection but it would be handy to know in the case of needing a replacement.

T - it is, there's one in mine, but it requires the cases to be split and it's the very FIRST part to go in. Since I was building the 1109 engine I had a great opportunity to do that, but really, nobody else would, it just doesn't make sense. Steve
Title: Re: Petcock kit install
Post by: T Cro ® on May 30, 2013, 08:30:55 PM
T - it is, there's one in mine, but it requires the cases to be split and it's the very FIRST part to go in. Since I was building the 1109 engine I had a great opportunity to do that, but really, nobody else would, it just doesn't make sense. Steve

Got ya...
Title: Re: Petcock kit install
Post by: MAN OF BLUES on May 30, 2013, 08:45:29 PM
It is proven the auto petcock is unreliable. Hence the proliferation of rebuild kits and manual replacements.
Besides the real problem is the poor design of the float valves.


well well, well.. bravo.
the auto/vac petcock works well...its the carbs that reall mattered...
actually until the Conccours was produced, (ne it's predecessor the veritable Ninja), we who owned Kaw bikes dealt with MIKUNI CARBS.... SLIDE CARBS....
No Diaphragms..., STEEL FLOAT NEEDLES sitting on BRASS SEATS..... all the wayback to the 60's.....


the redsign of the format using VACUME ASSITED THROTTLE SLIDES FOR ACCELERATION was the down fall of the modern bike; this provoked the VACUME ACTIVATED FUEL VALVE... which while a good design if USED DAILY,  created problems on bikes stored for decades... (who would store a bike that long?...... about 50,000 people evidently..)

with the redesign came the polymer tipped needles, which when a piece of grit rested in the rubber/brass seal area, embededded into the rubber... holding off the seat, and allowing fuel flow...., this rarely happened with the MIC's, and if it did, they overflowed and dumped fuel on the ground....(a-la- the SISF mod...), this didn't solve the problem, but it sure as HELL made it evident there WAS a problem..... and NO HYDRO-loks occured as a result.




C14 Cannot Hydro.
I like that.
COGZILLA needs a rod Job...
I don't like That,


BIG bore time.
Title: Re: Petcock kit install
Post by: Mettler1 on May 30, 2013, 09:25:24 PM
    Let's get real here. We're talking about bikes that are 10 to 20 yrs old or older. Petcocks and float valves don't last forever. You're buying bikes that have been sitting outdoors and in barns. Also with rusted tanks and ethanol gas. Blame Kawasaki?? This is a great bike with a hiccup that can kill! My petcock lasted 18 yrs and did NOT leak. Don't know about the float valves 'cause the petcock has to fail first and then the float valves. How long are they (float valves) suppose to last with a bunch of crap going through the carbs.
   Don't want to put in over flow tubes because you might get gas on the garage floor? If it doesn't end up on the garage floor the gas goes into the cyl. Hydrolock when you hit the starter!!
    If you have a better and fool proof way to prevent that, tell us about it.
    Yes TCro a manual petcock is great for the perfect people that shut them off EVERYTIME !! I'm not one of them!! :doh:  ;D ;D

   A man must know his limitations. 8)
Title: Re: Petcock kit install
Post by: Cholla on May 31, 2013, 11:39:49 AM
Constant velocity carbs forced vacuum operated petcocks? That's a riot!
If thatvwas the case manual petcocks wouldn't work! And we know they do work.
I would rather have gas in the engine than gas all over the garage floor which ignites when you turn on the lights or the water heater lights it.
I have used Dell'orto carbs for 25 years and on bikes back to 1975 models. Never had problems with junk in the seats or the carbs flooding-and all have/had manual petcocks that may or may not be shut off.
And again it is a proven fact the vacuum operated petcocks are unreliable.
Title: Re: Petcock kit install
Post by: Daytona_Mike on May 31, 2013, 03:26:05 PM
Auto petcocks are very reliable and much better than manual any day  and any time and that is a proven fact.  I already listed the reasons above. You need to read more.
Manuals fail too and people forget even more. This is why modern  carburated  bikes are all auto now and have been for a long long time.
 Leave a manual petcock on with a leaky float valve and you will have gas on the floor and in the engine and always 10x more than an auto petcock  would ever leave in either location.
You are far better off knowing you have a problem with overflow tubes  than sticking your head in the sand and hoping you dont have a problem.
Title: Re: Petcock kit install
Post by: Summit670 on May 31, 2013, 10:12:26 PM
With a vac petcock, just test it a few times a year by taking the fuel line off and see if it leaks.  That would offer some additional peace of mind.

Here is a question - when the fuel lines are full and the petcock off (manual or vac), if one of the fuel valves leak, the fuel in the lines and all the way back up to the petcock could trickle into the float bowl with the leaky valve. 

Is there enough fuel in the lines to pose a threat of hydrock?
Title: Re: Petcock kit install
Post by: Steve in Sunny Fla on June 01, 2013, 07:13:22 AM
With a vac petcock, just test it a few times a year by taking the fuel line off and see if it leaks.  That would offer some additional peace of mind.

Here is a question - when the fuel lines are full and the petcock off (manual or vac), if one of the fuel valves leak, the fuel in the lines and all the way back up to the petcock could trickle into the float bowl with the leaky valve. 

Is there enough fuel in the lines to pose a threat of hydrock?

What's going to introduce air into the fuel line to equalize the pressure differential and let the fuel flow out of the fuel line?

and Cholla - turn the lights on in your garage and ignite fuel on the floor?

Seriously, where do you guys get this stuff?  THINK ! Steve
Title: Re: Petcock kit install
Post by: Mettler1 on June 01, 2013, 07:21:20 AM
With a vac petcock, just test it a few times a year by taking the fuel line off and see if it leaks.  That would offer some additional peace of mind.

Here is a question - when the fuel lines are full and the petcock off (manual or vac), if one of the fuel valves leak, the fuel in the lines and all the way back up to the petcock could trickle into the float bowl with the leaky valve. 

Is there enough fuel in the lines to pose a threat of hydrock?
   If I have the fuel line disconnected from the petcock I don't know if there would be enough fuel in the line to fill the carb up to over flow into the cyl. assuming a stuck float valve. With my overflow tubes it would not be a problem other than a little gas on the floor. At least I would know I had a stuck float valve.
Title: Re: Petcock kit install
Post by: Mettler1 on June 01, 2013, 07:32:38 AM
  Although there were some good questions on this thread and some good answers we are starting to get into the "what if" . It pretty much "is" what it is and unless something better comes along we'll just have to deal with what we have at this moment. 8)

  I think I'll stay inside today. An asteroid might try to kill me today!!
Title: Re: Petcock kit install
Post by: Daytona_Mike on June 01, 2013, 10:34:54 AM
What's going to introduce air into the fuel line to equalize the pressure differential and let the fuel flow out of the fuel line?
Ooo Ooo , I know the answer to that one. I sound like Horshack on Welcome Back Kotter.
  I had issues when I was testing  external fuel filters and I would get occasional  vapor locks. Air was getting in to the fuel filter but how? I would fill the filter with solid fuel ,ride and stop there was  air is back in the fuel filter again.
When I bought clear fuel line I could see it. When the float needle shuts of fuel flow only air is sitting below the float valve-- small bubbles of air where squeezing upwards past the seat and making their way up the hose and collecting in the fuel filter.

I can only assume that when the petcock shuts off the remaining  short column  off fuel does not have enough pressure to prevent  air from leaking upwards  past  the float valve.
Title: Re: Petcock kit install
Post by: Steve in Sunny Fla on June 01, 2013, 10:50:12 AM
maybe a little Mike, but you never saw your fuel line completely empty into the carbs though, did you?

i think the migration you saw had more to do with the heated fuel in the line exhibiting some pressure from expansion. Once equalized, it would stop, not drain entirely down into the carbs.  Steve
Title: Re: Petcock kit install
Post by: Daytona_Mike on June 01, 2013, 01:08:44 PM
maybe a little Mike, but you never saw your fuel line completely empty into the carbs though, did you?

i think the migration you saw had more to do with the heated fuel in the line exhibiting some pressure from expansion. Once equalized, it would stop, not drain entirely down into the carbs.  Steve
Your right, the fuel line never went empty. Just  air collection in the fuel filter.
Title: Re: Petcock kit install
Post by: Cholla on June 03, 2013, 04:33:47 AM
Steve-I am thinking. Gas fumes collect and a spark causes an explosion. The fumes are explosive. Seen it happen. How about homes with the furnace and water heater in the garage?
THINK!
And if the vac operated petcocks are so reliable why are we even having this discussion?