Author Topic: petcock  (Read 1678 times)

Offline yogidozer

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petcock
« on: November 27, 2021, 08:04:26 AM »
Most replace the electric petcock with a manual shut off, I did about 20 years ago.
But why doesn't someone make one like the older version, flip to on/off/reserve?
Will one from an older model fit an EV?

Offline guzzisteve

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Re: petcock
« Reply #1 on: November 27, 2021, 12:48:27 PM »
Yes, they fit. The hole is larger for a larger amount volume to fuel pump. That's all.
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Offline yogidozer

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Re: petcock
« Reply #2 on: November 27, 2021, 02:03:59 PM »
Yes, they fit. The hole is larger for a larger amount volume to fuel pump. That's all.
Thanks for the answer  :thumb:
You would think someone went to the trouble to make a manual petcock, they would make one with a reserve.  :rolleyes:
« Last Edit: November 27, 2021, 02:17:43 PM by yogidozer »

Online bmc5733946

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Re: petcock
« Reply #3 on: November 27, 2021, 02:24:57 PM »
Any petcock used on fuel injection needs to be high flow without restriction so that gravity can feed enough fuel to feed the electric pump which flows much more fuel than the injectors can deliver with the excess being returned to the tank. Restrictions in fluid systems build heat, heated fuel is not really what we want /  need for engines hence the increased flow and return to tank etc..

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Re: petcock
« Reply #3 on: November 27, 2021, 02:24:57 PM »

Offline Huzo

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Re: petcock
« Reply #4 on: November 27, 2021, 02:35:52 PM »
I misunderstood..
When I read the title, I thought it was about pets... :popcorn:

Offline yogidozer

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Re: petcock
« Reply #5 on: November 27, 2021, 02:44:51 PM »
I misunderstood..
When I read the title, I thought it was about pets... :popcorn:
Afraid to ask what you are petting :shocked:

Offline yogidozer

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Re: petcock
« Reply #6 on: November 27, 2021, 02:53:59 PM »
rodekyll, so you are saying it can't be made?
That explains why someone hasn't come up with one.
Thanks for your input, I figured there must be a reason.
Have the manual one now, PITA to turn it when my hand is cold, maybe carpal tunnel, IDK

Offline guzzisteve

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Re: petcock
« Reply #7 on: November 27, 2021, 03:28:56 PM »
Thanks for the answer  :thumb:
You would think someone went to the trouble to make a manual petcock, they would make one with a reserve.  :rolleyes:
You have a light for reserve. I did not design it.
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Offline guzzisteve

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Re: petcock
« Reply #8 on: November 27, 2021, 03:37:19 PM »
rodekyll, so you are saying it can't be made?
That explains why someone hasn't come up with one.
Thanks for your input, I figured there must be a reason.
Have the manual one now, PITA to turn it when my hand is cold, maybe carpal tunnel, IDK
If you look to the past Cal 3 FI of 1993 had 2 regular petcocks no reserve, just went to a big T and to pump. Had a light for reserve. Same tank for both carbs & FI in 93.
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Offline yogidozer

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Re: petcock
« Reply #9 on: November 27, 2021, 03:40:54 PM »
You have a light for reserve. I did not design it.
Yes, I know that. And I keep track of mileage and haven't run out yet.
I went for a multi state ride on Thanksgiving, only to find many gas stations were not open.
Nice to have reserve option like every other bike I've had.
I live, and ride in a pretty rural area, rarely on highways, so gas stations are few.

Offline Wayne Orwig

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Re: petcock
« Reply #10 on: November 27, 2021, 03:50:15 PM »
rodekyll, so you are saying it can't be made?
That explains why someone hasn't come up with one.
Thanks for your input, I figured there must be a reason.
Have the manual one now, PITA to turn it when my hand is cold, maybe carpal tunnel, IDK

The fuel flowing through the pump cools and lubes it. If you put on a tap with a reserve, and run it dry and switch to reserve, you will eventually toast the pump.
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Offline lucky phil

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Re: petcock
« Reply #11 on: November 27, 2021, 04:02:44 PM »
OOOps.  I posted a bad reply here -- thought it was the other fuel topic.  Yes, I'm saying that given the single petcock on your tank you need to stay with the large diameter, single position petcock.  I prefer the manual petcock in that it doesn't leak when off (makes taking the tank off easier).  However, I'm not real thrilled with the thumbwheel valve.  It tends to bind.

I have a solution for this I documented on the V11 Lemans forum.

https://www.v11lemans.com/forums/index.php?/topic/21761-manual-fuel-tap-issues/

Ciao
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Offline lucky phil

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Re: petcock
« Reply #12 on: November 27, 2021, 04:09:19 PM »
Yes, they fit. The hole is larger for a larger amount volume to fuel pump. That's all.

Not strictly true. The outlet for the manual and electric fuel tap is 12mm OD but if you disassemble a solenoid fuel tap you will find the inlet size id small, something like 4mm. So effectively you have the same overall fuel delivery rate as an old style lever tap. I was a bit surprised when I disassembled a V11 solenoid tap as judging from the outlet I assumed the same as you but it seems not.

Ciao

« Last Edit: November 27, 2021, 04:09:55 PM by lucky phil »
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Offline lucky phil

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Re: petcock
« Reply #13 on: November 27, 2021, 04:46:49 PM »
The fuel flowing through the pump cools and lubes it. If you put on a tap with a reserve, and run it dry and switch to reserve, you will eventually toast the pump.

This is not really an issue. Every time you start to run out of fuel on your injected bike do you worry about the fuel pump being run dry? So with a manual tap and a fuel pump when you start to run out of fuel the engine starts to cough and splutter and in the time it would take you to switch to reserve you're not going to damage the pump. If you run your bike out of fuel repeatedly same, same. As soon as the engine stops rotating the pump also stops. The whole fuel cooling and lubricating the pump and motor thing is a bit exaggerated in reality.
Modern EFI engines don't use fuel taps in the main because they just aren't considered necessary anymore. The electric solenoid tap along with the vacuum operated tap were originally implemented for US DOT regulations that required the fuel feed system be fail safe shut in the event of an accident where the fuel tank was separated from the bike there wouldn't be fuel being expelled from an open fuel tap. Now with integral pumps and regs they are obsolete. The only time I ever operate the manual fuel tap on my V11 Sport is when I remove the tank, otherwise it's open all the time.   

Ciao 
« Last Edit: November 27, 2021, 04:47:28 PM by lucky phil »
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Offline yogidozer

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Re: petcock
« Reply #14 on: November 27, 2021, 04:52:13 PM »
This is not really an issue. Every time you start to run out of fuel on your injected bike do you worry about the fuel pump being run dry? So with a manual tap and a fuel pump when you start to run out of fuel the engine starts to cough and splutter and in the time it would take you to switch to reserve you're not going to damage the pump. If you run your bike out of fuel repeatedly same, same. As soon as the engine stops rotating the pump also stops. The whole fuel cooling and lubricating the pump and motor thing is a bit exaggerated in reality.
Modern EFI engines don't use fuel taps in the main because they just aren't considered necessary anymore. The electric solenoid tap along with the vacuum operated tap were originally implemented for US DOT regulations that required the fuel feed system be fail safe shut in the event of an accident where the fuel tank was separated from the bike there wouldn't be fuel being expelled from an open fuel tap. Now with integral pumps and regs they are obsolete. The only time I ever operate the manual fuel tap on my V11 Sport is when I remove the tank, otherwise it's open all the time.   
 

Ciao
My thought exactly. I would rarely use reserve anyway.

Offline kingoffleece

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Re: petcock
« Reply #15 on: November 27, 2021, 06:56:34 PM »
So what happens when an electric petcock fails?
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Online John A

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Re: petcock
« Reply #16 on: November 27, 2021, 08:21:19 PM »
rodekyll, so you are saying it can't be made?
That explains why someone hasn't come up with one.
Thanks for your input, I figured there must be a reason.
Have the manual one now, PITA to turn it when my hand is cold, maybe carpal tunnel, IDK



I generally only turn it off if I’m taking the tank off. Another plus for injection- no floats!
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Offline Kiwi_Roy

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Re: petcock
« Reply #17 on: November 27, 2021, 09:07:33 PM »
So what happens when an electric petcock fails?
I think the way they fail is the wires break off where they exit the body, strapping the wires to the valve body with a ty-wrap will prevent that.
If the Valve fails you can pull it apart and remove the valve poppet.
I must admit i'm a fan of the electric valve, I would never swap it out for a mechanical one that you might leave closed.
The Low fuel light gives lots of warning.
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Offline yogidozer

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Re: petcock
« Reply #18 on: November 27, 2021, 10:01:39 PM »
I think the way they fail is the wires break off where they exit the body, strapping the wires to the valve body with a ty-wrap will prevent that.
If the Valve fails you can pull it apart and remove the valve poppet.
I must admit i'm a fan of the electric valve, I would never swap it out for a mechanical one that you might leave closed.
The Low fuel light gives lots of warning.
You're lucky, mine failed about 20 years ago?
Manual one since then.

Offline lucky phil

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Re: petcock
« Reply #19 on: November 28, 2021, 01:32:14 AM »
I think the way they fail is the wires break off where they exit the body, strapping the wires to the valve body with a ty-wrap will prevent that.
If the Valve fails you can pull it apart and remove the valve poppet.
I must admit i'm a fan of the electric valve, I would never swap it out for a mechanical one that you might leave closed.
The Low fuel light gives lots of warning.

The only reason to ever close the manual tap is to remove the tank otherwise you just leave it open.

Ciao
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Offline Kiwi_Roy

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Re: petcock
« Reply #20 on: November 28, 2021, 08:06:15 AM »
When I had my VII Sport it just had the electric petcock on the left and the pressure relief valve on the right returning the fuel to a significant wasted volume on the right side of the hump.
If you ran low you could tilt the bike over and access the fuel on the right but the pump just chucked it back again.
I puzzled over that for a long time then I hit on a solution, I added an internal pipe to the relief valve return that directed the fuel over the hump to the left side.
I'm not sure how effective this was because I sold the bike shortly after but it made me feel better LOL
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Offline lucky phil

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Re: petcock
« Reply #21 on: November 28, 2021, 03:26:17 PM »
When I had my VII Sport it just had the electric petcock on the left and the pressure relief valve on the right returning the fuel to a significant wasted volume on the right side of the hump.
If you ran low you could tilt the bike over and access the fuel on the right but the pump just chucked it back again.
I puzzled over that for a long time then I hit on a solution, I added an internal pipe to the relief valve return that directed the fuel over the hump to the left side.
I'm not sure how effective this was because I sold the bike shortly after but it made me feel better LOL

I spent quite a lot of time looking at doing this using my spare tank and fittings I have but couldn't figure a way of doing it without having a foot long or more section of pipe unsupported inside the tank which I figured after a while being subjected to fuel sloshing around and vibration would eventually break. Flex hosing wasn't an option for much the same reason, trying to keep it positioned in the tank plus the return fuel is generally aerated and I didn't want to dump it straight back to the pump inlet. I gave up on the effort/reward ratio and decided to keep closer attention to my fuel quantity via the warning light and mileage indication.


Ciao
« Last Edit: November 28, 2021, 03:27:39 PM by lucky phil »
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Offline Kiwi_Roy

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Re: petcock
« Reply #22 on: November 29, 2021, 12:03:40 AM »
I spent quite a lot of time looking at doing this using my spare tank and fittings I have but couldn't figure a way of doing it without having a foot long or more section of pipe unsupported inside the tank which I figured after a while being subjected to fuel sloshing around and vibration would eventually break. Flex hosing wasn't an option for much the same reason, trying to keep it positioned in the tank plus the return fuel is generally aerated and I didn't want to dump it straight back to the pump inlet. I gave up on the effort/reward ratio and decided to keep closer attention to my fuel quantity via the warning light and mileage indication.

Ciao
I think it was less than 6", just has to be higher than the centre of the tank, i used a piece of instrument tubing or brake line, I can't recall the details now.
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Offline lucky phil

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Re: petcock
« Reply #23 on: November 29, 2021, 12:44:34 AM »
I think it was less than 6", just has to be higher than the centre of the tank, i used a piece of instrument tubing or brake line, I can't recall the details now.
Ok Roy. I actually remember what I was considering now. The return pipe from the reg feeding the other side of the tank is actually a bit pointless as the issue is "using" the fuel from the return side of the tank. As soon as you fill the tank it's trapped there no matter where you return the fuel to. I was trying to figure a way to organise a link pipe from the return side to the pump pickup side either internally or externally so the pump would pickup fuel from both sides but the return fitting is a bit to small to accomplish both return duties and transfer duties from one side to the other. Eventually I just decided to use the later in tank pump fuel tank because the whole external hose system is also neater but then found it won't fit on my bike due to the Daytona engine being fitted. What you could have is a remotely mounted reg holder as shown which I have and a "T" piece fitted to the rhs return fitting on the tank and an external link hose to the other side but the external hosing is messy enough and space is very limited. Too hard I think for the gain.







« Last Edit: November 29, 2021, 12:46:51 AM by lucky phil »
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Offline Kiwi_Roy

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Re: petcock
« Reply #24 on: November 29, 2021, 04:50:59 AM »
Yes when you run out of fuel you still have a couple of litres trapped on the RH side. You can lean the bike right over to the left and this fuel will run to the side the pump draws from but then the pump throws it straight back to the RH side.
Running out of fuel one day I discovered I could keep the engine struggling along by weaving.
I don't remember the exact details but my pipe was a tight fit into the regulator port that screws up into the tank, it had a 45 bend at the top to squirt the fuel over the hump to the left side, as I said I never really had to test it because I sold the bike.

Electric fuel pump (from the Efiman document) https://dpguzzi.com/efiman.pdf
This is a roller positive displacement pump with the motor submerged in the fuel. The motor is a permanent magnet carbon brush type. When the impeller is turned by the motor, the fuel is moved from the intake orifice to the delivery port. The amount of fuel is determined by the rollers which adhere to the outer ring while the motor is turning. The pump has a check valve to prevent the fuel circuit emptying when the pump is not running. It is also equipped with an overpressure valve which short-circuits the delivery when the pressure is over 74 psi to prevent the pump motor from overheating.
Delivery: 26.5 gal/hour at 44 psi with 12V power supply. The pump draws about 4.5 amps.

Note you can measure the pump current easily with an ammeter connected to the relay socket 30 - 87, I found it closer to 4 Amps. Do this test with the key turned Off
Measuring the pump current will also show up other things like a blocked suction about 4.3 Amps
Plugged filter or regulator up to 9 Amps (or a pump that has gummed up with sitting for years with gas inside, usually quite easy to free up)
If you measure the relay socket 87 to chassis thats the pump windings 1.3 Ohms (using Ohms law 12V / 1.3 Ohms = 9.2 Amps, very close to the plugged filter)
It only draws 4 when spinning because it also acts as a generator producing back EMF
« Last Edit: November 29, 2021, 05:24:52 AM by Kiwi_Roy »
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Offline yogidozer

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Re: petcock
« Reply #25 on: November 29, 2021, 05:18:27 AM »
I started this thread in hopes that someone made, or knew of a petcock from another bike would work.
Never have run out, I keep track on my odometer. Places I ride seem like gas stations are closed down, or limited hours.
So now I'll just carry these, especially on holidays when gas stations are closed.

https://twistedthrottle.com/shop/luggage/fuel-bottles-and-mounts/msr-30oz-fuel-bottle/
« Last Edit: November 29, 2021, 05:24:12 AM by yogidozer »

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Re: petcock
« Reply #26 on: November 29, 2021, 08:14:58 AM »
Minor thread hijack...
If you are going to install manual on/off/ reserve in place of electric petcocks on a carbureted bike (Sport 1100), note that the fuel tank was designed with Reserve... Effective range on Reserve is about 10 miles. :shocked:

Offline yogidozer

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Re: petcock
« Reply #27 on: November 29, 2021, 03:19:29 PM »
Minor thread hijack...
If you are going to install manual on/off/ reserve in place of electric petcocks on a carbureted bike (Sport 1100), note that the fuel tank was designed with Reserve... Effective range on Reserve is about 10 miles. :shocked:
My 95 Spot never had, and never will have electric petcocks

Offline lucky phil

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Re: petcock
« Reply #28 on: November 29, 2021, 04:08:32 PM »
I started this thread in hopes that someone made, or knew of a petcock from another bike would work.
Never have run out, I keep track on my odometer. Places I ride seem like gas stations are closed down, or limited hours.
So now I'll just carry these, especially on holidays when gas stations are closed.

https://twistedthrottle.com/shop/luggage/fuel-bottles-and-mounts/msr-30oz-fuel-bottle/

Why? what's wrong with the manual version that's already available? No reserve? jamming? (which can be rectified) The manual screw tap is actually a good design just needs a little fettling.
I think you could use any 5/16 outlet tap personally but you would need an adaptor to go from the 5/16 tap outlet to the 12mm pump inlet.

Ciao
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Offline yogidozer

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Re: petcock
« Reply #29 on: November 29, 2021, 04:18:09 PM »
Why? what's wrong with the manual version that's already available? No reserve? jamming? (which can be rectified) The manual screw tap is actually a good design just needs a little fettling.
I think you could use any 5/16 outlet tap personally but you would need an adaptor to go from the 5/16 tap outlet to the 12mm pump inlet.

Ciao
I have and like the manual one. Where I ride, often gas stations are few and far between.
Thanksgiving I headed for a multistate ride. Thinking gas stations might be closed (they were) I added some gas I had for lawn tractor.
Now my odometer wasn't going to let me know when I was getting close to empty.
Not sure how long after low fuel light came on before sputter---stop.
Brought a camp stove container, but rather have a reserve option.
No big deal, just thought someone might make a on/off/reserve replacement

 

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