QuestionI have discovered petrol leaking from one of the carburetors of my 1998 yamaha virago .This only happens following a run and then when it is siting for a few hours .It does eventually dry up after sitting overnight .I have the fuel switch off .Would this be difficult to cure as i am not really mechanically minded .
AnswerHi Lynda,
Disassembly and cleaning of the carburetors may be a bit involved for the non-experienced, though it can be done.
Review the following tech files and decide if the task is for you.
Visit this Virago tech resource for more assistance:
http://viragotech.com/phpBB/portal.php
I return tech information files by email. There was no email address with your question as requested and explained in my instructions. Reply with your email addy if you want more tech files.
Respectfully,
Mark Shively
Bad Gas
By Mark Shively
Gasoline goes bad with time and in as little as 3-4 weeks. This effect is known as varnishing. Jets and passageways within carburetors become obstructed when varnishing occurs.
Liquid gasoline changes chemically into a gel like substance. Advanced stages of varnishing results with the solid gel changing into a crystal powder substance. Interior carb surfaces are etched in the process and may require carb replacement.
The choke and pilot circuits with most motorcycle carburetors share passageways. When pilot jets become obstructed, the choke circuit compensates and allows engine to start and idle with choke, but stalls without choke. Learn more about cleaning carburetors, review the information below. Order Service Manuals (repair manuals) here: www.repairmanuals.com View microfiche parts and check part prices here: www.bikebandit.com
Carb Cleaning 101
By M. Shively
The elements of internal combustion engines are; correct fuel/air ratio, spark at right time, adequate cylinder compression.
Motorcycle and ATV carburetors have many passageways and openings to check and clean. Subtle to radical effects on engine performance occur when jets and passageways become obstructed. Vacuum leaks and carburetor synchronization also effect performance and should be checked and adjusted. The following procedures are a helpful guideline.
Carb Cleaning 101
Warning: Remove all rubber (Neoprene) parts before applying chemicals to carburetor parts. These parts usually include vacuum diaphragms, needle valves, o’rings, hoses, and other parts. Spray cleaners may damage these parts. Do not disassemble individual carbs from the carb brackets.
Air & Fuel Passageways: Trace individual fuel and air circuit passageways from beginning to end. Machines can only drill straight paths through castings to form passageways. A change of direction or angle means drilling additional connecting passageways. Access holes left by the drilling process are plugged with brass or bronze beads. Inspect and clean each passageway with spray cleaner, brushes, pipe cleaners, and compressed air. Many household items can be useful cleaning tools. Remove any discoloration and debris from carbs. Look for carb spray cleaner to exit from one or more passageways. Chase immediately with compressed air.
Jet Cleaning: Inspect jets by holding to light and look through them. You should see an unobstructed round hole. Clean the jets with one or more of the following; jet-cleaning wires, soak solutions, carb spray cleaners and compressed air. Re-inspect jets after cleaning and install when clear of obstructions. Some main jets have paper-like gaskets. Most have metal spacers between the jet and the emulsion tube. Some screw directly into a brass emulsion tube, which is machined for a 7mm wrench at its float chamber, exposed base.
Inlet Fuel Valve: Inspect the needle valve & spring. Press down the tiny metal rod that protrudes from the butt or float end of the needle valve. The spring should move freely and return the rod to its location. Check the needle valve’s seat area for a groove or other wear. It should appear highly polished. Some needle valve seats are rubber and wear may not be visible. Inspect the needle valve jet seat. You can clean the jet seat with Q-tips and semi-chrome polish if necessary.
Carb Body Castings: Blow air through the atmospheric vent holes located on the dome of each float bowl chamber. Air should exit via hoses or brass nipples. Inspect the emulsion tubes and passageways (cast towers that jets thread into) for discoloration and debris. Clean interior emulsion towers with a soft bristle gun cleaning brush. Clean each Venturi (main carb bore).
Needle Jets & Jet Needles: Clean the needle jets, jet needles, and emulsion tower (main jet screws into). Clean the emulsion tube (pipe between needle jet and main jet) (Main Jet may screw into emulsion tube). Jet needles are part of the throttle slides. See below…
Throttle Slides: There are several types of throttle slides: Mechanical linkage, vacuum, diaphragm, and cable. Disassembling the jet needle from the slide is not always required for cleaning. If you have vacuum piston type throttle slides (large diameter solid metal slide), avoid cleaning the lubrication from sides and caps. If piston type check cap vents and passageways with air. Clean if necessary and re-lube. If you have rubber vacuum throttle diaphragms, inspect for dry rot, defects, and tears by gently stretching rubber away from center. Do this until all areas around diaphragm have been inspected. Replace any defective part as described above. Clean carb body areas around diaphragm including air passageways and air jets. Diaphragms have a locator loop or tab fabricated into their sealing edge. Observe this locator upon reassembly. Avoid pinching the diaphragm when reinstalling caps.
Fuel Screws: Fuel screws have sharp tapered ends. Carefully turn one fuel screw in while counting the turns until it seats lightly. Warning: These screws are very easily damaged if over tightened into their seats. Record amount of "turns-in" and remove the fuel screw, spring, washer, and o'ring. The fuel screw is part of the enrichment (choke) circuit...clean passageways as described above. When carbs are assembled, spray low PSI compressed air into diaphragm air vents located at intake side of carbs. Throttle slides should rise, then fall when air is removed. Lightly lube external moving linkages. Reinstall carbs and follow through with carburetor synchronization.
Throttle Cables: Lubricate cables periodically. If cables are disconnected from carbs or removed for replacement, etc . . . remember cable routing and ensure proper reinstallation routing. Avoid bread-tying, sharp bends, and pinching cables. Adjust cables so throttle grip has about 5mm of play or throttle slides or butterfly valves may not open completely (full throttle)(wide full open).
Float Bowls: Inspect float bowls for sediment, gum or varnish, crystallization, and defects. Clean all pipes, tubes, passageways, and embedded jets with cleaners and compressed air. Remove and clean the drain screw and area. Inspect bowl gasket and replace if necessary. Clean and inspect overflow pipes and tubes, look for vertical cracks.
Floats: There are several types of float materials: plastic, brass, black composite, tin, and others. Handle floats carefully. Avoid bending, twisting, denting, or other means of mishandling. Most floats are adjustable by bending a small metal tab near the float axle end. Do not change the float adjuster tab unless tuning fuel service levels. Clean metal floats by soaking or by spraying cleaner and wiping clean. Other material type floats may require replacement if cleaning is necessary. Inspect the needle valve (float valve) and seat. Check needle valve’s spring loaded pin. It should depress and return smoothly and without resistance. Check the needle valve tip for a worn groove. Replace needle valve and seat if either symptom exists. The valve and valve seat wears together and must be replaced as a set.
Synchronization: This is a fine adjustment performed usually and preferably with the carbs installed and the engine running. The unusual part is performed with gauged wire with the carbs on the workbench. Carburetor synchronizing balances Venturi vacuum at the exhaust side of each carburetor, resulting with smooth idling and optimized performance at all throttle openings. Synchronization is checked using a set of gauges. Gauge sets are available in air vacuum type, liquid mercury type, and steel rod type. The Morgan Carb Tuner II is the most accurate tool in my opinion. Mercury vapors are toxic and Mercury is a hazardous material. The gauges are connected to vacuum ports on the intake manifolds via nipple tubes or if sealed with screws, sync gauge adapters will be needed. With the engine running at temperature, and with a fan or means of forced convection aimed onto the engine, the carbs fuel screws and idle are adjusted, then the synchronization is adjusted via adjustment screws on the carbs. A reserve fuel tank is recommended for convenience of accessing carbs during this procedure. See gauge instructions and repair manuals for detailed use of synchronization gauges.
Notes: While carbs are apart, record the jet sizes. Look for a very small number imprinted on the body of the jets. Verify that numbers are the same for all jets on models with in-line cylinders. A few transverse-4 models and V-engines, the inner and outer carbs use some different size jets. It is important to note jets sizes and locations. If you have dial or veneer calipers, measure and record float heights. Perform measurements with floats just touching needle valves, though not depressing the needle valve rods. Replace fuel and vacuum hoses. Be sure to use fuel rated hose for fuel. Install or replace in-line fuel filters. It’s a good time to remove and clean interior petcock fuel filters. Inspect carb manifolds for dry rotting; inspect all clamps and air ducts. Inspect, clean, lube, and/or replace air filter(s).
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VIRAGO FUEL SYSTEMS
The main points about fuel tanks are these: they need a way of letting fuel out to the carbs, and they need a way to let air in as the fuel goes out, to avoid a vacuum buildup in the tank. We will call this "venting" or "breathing."
The tank should have a "reserve" function that will allow you to access an additional supply of fuel when you start to "run out of gas" and thus allow you a few more miles of driving to find the nearest gas station.
And finally, there are safety considerations, mainly involving the situation where the bike falls over on its side. The concern is that we don't want fuel spilling out all over the place when this happens, so we need to block the fuel path and the venting path, so that the fuel stays in the tank in a "down" situation.
EARLY YEARS -750's AND 920's
Viragos and RH, RJ chain drive models offered from '81 to'83 have a gravity feed system. The fuel runs downhill from the tank through fuel lines to the carbs. Some models have one petcock and some two, but the method is the same. One petcock just requires a splitter and two pipes to feed the carbs.
The petcocks are vacuum operated petcocks. This means that they have a little diaphragm and valve set-up, which responds to engine vacuum and allows fuel to flow only when the engine is running and supplying vacuum. This is how things work when the petcock lever is set to the "on" or "run" setting. So we see that the "on" setting is actually the "off" setting when the engine is not running. So if the engine quits for any reason (as in a "down" situation), the petcock(s) will automatically close and prevent the fuel from flowing out.
These petcocks also have two other lever settings:
The "prime" setting bypasses the vacuum function and allows fuel to flow at all times, even when the engine is stopped. The purpose of this setting is to allow the carb float bowls to be filled when the engine is not running. Note that if you run your petcock(s) on the prime setting all the time, you lose the safety feature provided by the vacuum petcock. Note also that on this setting, fuel is prevented from flowing out through the carbs, into cylinders, etc.) only by the float valves in the carbs, which close when the carbs are full. Should one of these float valves stick open or leak, you then get flooding through that carb.
The "reserve" setting is used to access an additional amount of fuel when you start to run out. Here is how this works. These petcocks have inlet towers, which stick up into the tank. In the "on" position, fuel flows down to the petcock through an opening high on the tower. So when you "run out of fuel" you actually have some more fuel sitting in the bottom of the tank, which lies below this high inlet. When you turn the petcock lever to "reserve," a lower inlet near the bottom of the tower opens, so you can gain access to this last bit of fuel in your tank.
All these older tanks breathe through venting passages in the gas cap. When the bike goes over, and a little ball bearing rolls along a little passage in there and blocks the flow of fuel through this vent.
LATER 700'S AND 750'S
Starting in 1984, things changed a little for all 700's ('84 to '87) and 750's ('88 to the end of the run).
First, a fuel sender and low fuel light were added to warn us of a low fuel condition and encourage us to switch the petcock to reserve. The sender (which resides in the fuel tank) is actually a switch designed to turn the warning light on when the supply of gas available through the high tower inlet is about to run out.
The second change relates to venting. California models were now vented through a hose running to a charcoal canister which is designed to collect fumes from the tank (and the carbs) when the bike is at rest, and return them into the engine to be burned when the engine runs. This breather hose also has a "rollover" valve in it, which performs the same function as the ball bearing in the earlier gas caps. When the bike goes over, a floating ball rolls into a seat and prevents fuel from pouring out the vent. To my knowledge, Canadian and "49 state" bikes" retained this gas cap breathing method.
VIRAGO 1000's AND 1100's
With these models almost everything changes big time.
Gone is the petcock, together with its prime and reserve functions. The fuel now flows all the time from the main tank to an added lower tank through a big fuel pipe. Main tank breathing is handled as in the 750's, but there is also a breather pipe between the main and lower tanks.
Added are:
The second (lower) fuel tank of about .6 gallon capacity (noted above).
A fuel pump
A fuel pump controller (electrical black box)
Here's how things work. All fuel flows from the main tank, through the lower tank, through a fuel filter, to the fuel pump. It is one continuous system. The fuel pump (a low pressure "on-demand" type pump) then pumps fuel to the carbs. There is no physical reserve fuel supply.
Running things is the fuel pump controller. This black box has several functions.
First, it tells the fuel pump to pump when the ignition is on, the engine is running, and you have adequate fuel.
Second, it acts as a safety device to prevent the pump from pumping when the engine quits running-- as in a "down" situation. It stops the fuel pump about 5 seconds after the engine quits (or is not) running, even though the ignition switch is still on. You will notice this effect also when you first turn on the ignition. Before the engine starts, the pump will often give a few burps to fill the float bowls. However, it can take several turns of the switch to fill empty float bowls...
Third, the controller now provides the "reserve" function. You still have a fuel level sender and a fuel light. When the fuel goes low in the main tank, the sender unit sends a signal to the low fuel warning light, which goes on. Now it also sends a signal to the fuel pump controller. Shortly after the warning light goes on, the fuel pump controller partially shuts down the fuel pump, so that your engine does not completely quit, but does start to starve for fuel. The effect (to the rider) is that you feel like you are running out of gas. You then hit the "reserve" switch on your handlebar, and this tells the controller to turn your fuel pump back on full so that you can access the remaining fuel, which is, no doubt, mostly in that lower tank. Therefore, my friend that is how it works. It is just a "running out of gas" trick played on you by Yamaha and the fuel pump controller.
TROUBLE-SHOOTING THE SYSTEM
!!! NOTE THAT WE ARE DEALING WITH FUEL HERE. FUEL CAN GO BOOM! TAKE ADEQUATE PRECAUTIONS, OR HAVE AN EXPERIENCED MECHANIC DEAL WITH YOUR FUEL SYSTEM PROBLEMS. !!!
PETCOCKS
Sucking on the vacuum lines can tell you whether the vacuum function is working. Petcocks can also start to leak. You can try disassembling, cleaning and reassembling. If this does not work rebuild kits are available from K&L Supply Co. (through your dealer, K&L does not sell direct.)
GAS CAPS/VENTING PROBLEMS ('81-'83 MODELS)
If the venting passages in your gas cap are plugged you will not get far. A typical symptom is the bike that will run for a while then just quit. Then after a rest, it will run again. The breathing problem causes a vacuum buildup, which eventually prevents the fuel from dropping/flowing properly. You can try running on a back road with the gas cap ajar (at your own risk!), and see if the problem goes away. Gas caps can be partially disassembled. Be very careful if you try this, since there are little springs and balls in there that can get away from you easily, never to be found again. Then some carb cleaner sprayed here and there and some air may be able to clear out any blocked passages.
RUSTY TANKS
Several cleaning and coating products are available, Kreem being one of them. This is tedious, messy, smelly work, but your tank will be restored. The small lower tanks on later models can get rusty as well and shouldn't be ignored.
FLOODING CARBS
If your carbs floods on the “prime” setting, your float valves are sticking. Tap your carbs a little to see if the problem clears. Otherwise, replace your float valves.
VENTING PROBLEMS ON LATER MODELS
From '84 on, the bigger Viragos have venting pipes with "rollover valves" in them to prevent fuel from flowing out in the event the bike goes over. Check to see whether your rollover valve is stuck closed. Clean or replace if it is giving trouble. If you suspect that, the problem is with your charcoal canister (California models), just disconnect the breather hose from the canister. Attach a bit of air breather type foam on it with a small plastic tie and let it breathe into the air.
FUEL WARNING LIGHT/FUEL LEVEL SENDER PROBLEMS
Check the bulb, check the fuel sender as per instruction in the Factory Service Manual. (I don't give specs in my articles). Thanks to our resident electronics guru, Rob Underhill from Australia, who has been advising me on the electrical aspects of Viragos, we now know how fuel senders work. (I once had one out and tried to discover the secret--without success, since there are no moving parts and resistance measurements just didn't make any sense to me.) Turns out what we have in there is a thermistor. This small electronic component receives 12 volts but won't pass very much of it through when it is cold --as in constantly bathed in fuel. Once the fuel gets low and it is exposed to air in the tank, the current is sufficient to heat it up. Once it gets hot enough more current passes through it, enough to light the low fuel light. We are working on a source for these thermisters. With a little care and a little solder, this becomes a $4 repair, as opposed to megabucks for a new fuel sender from Yamaha. Update: Rob was able to find one at an outfit called RS Components, Part number 256-102. You can find RS components on the net in the UK. If anyone has luck in the US, I'd be pleased to hear about it.
FUEL PUMP
If you suspect fuel pump problems, drain your carbs. The find the hot wire to your fuel pump and give it 12 volts. The pump should operate full bore until the float bowls are full and the float valves shut, at which time the pump should stop. If the pump isn't working continuously in this situation, you are probably looking at a new pump. Pumps seldom fail in my experience.
FUEL PUMP CONTROLLER
Drain your carbs. Turn your ignition on and see if you get 5 seconds of action. Run tests given in factory service manual. If you decide, the controller is bad, price one, and see how badly you want to retain it. If you swoon at the price, here is a solution that I do not recommend to you because if you do it this way you will lose the engine cutoff safety feature, as well as your reserve function.
But anyway, here it is. Find the wire that supplies power to your TCI (ignition). This will be after the main switch AND the engine stop switch. Tap into this wire and run a wire to a horn type relay (Radio Shack sells a good 30 amp, 12 volts relay. Bosch also makes one with a nice connector set-up). Ground the other side of the relay. Then run a wire with an in-line fuse, say 5 amps, directly from the battery through the relay and connect it to the hot wire running to the fuel pump.
If you do, this here's how it will work. With both ignition and the engine stop switch on, the fuel pump will be on at all times. Fuel flow will be checked by the float valves only. No five second shut offs when you turn the ignition key on or if the engine quits (safety feature gone!) If you know you are going over, try to hit the engine stop switch before you pass out or whatever, otherwise you pump will stay active, and fuel could be lost. You will now have to figure your gas stops on your odometer, and your warning light, which will probably still work. If you know your gas, mileage this should not be too hard. But there will be no "running out of gas" feeling to warn you and if you don't fill up, your pump will keep pumping until the last drop is gone.
Random note on fuel systems: The Viragos covered in this article have gravity feed, or electric fuel pump systems. But the XV 500 and some other Yamaha models have fuel pumps driven by vacuum from the engine. If you have one of these pumps and run out of gas, you may have to run your starter a good long while for these pumps to refill the float bowls. Go easy on that starter system and don't crank it continuously. Or you could possibly pull the fuel lines off from the carbs, and prime the bowls directly.
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Yamaha Maxim Leaky Petcock Problem & Solution
Among some common "issues" experienced by the Maxim-x is a leaky petcock that can lead to some extreme circumstances
The Maxim-X comes equipped with a vacuum-operated petcock that is automatically OFF when the engine isn't running. Vacuum from the running engine is used to open the petcock and allow fuel to flow when switched to ON or RES. However, after the passage of time, the Maxim-X petcock may begin to leak internally. Despite a non-running engine, fuel can begin to leak past the vacuum diaphragm's plunger seal and into the carburetor float bowls when no fuel is expected. If this happens in combination with a leaky float valve or two, then it's possible that even when the bike is unused, fuel will leak through the petcock, into the float bowls, past the leaky float valve(s) until the fuel eventually overflows into the intake boots. If that happens, it's only a matter of time before the excess fuel finds its way through the intakes into the cylinders and past the pistons into the crankcase.
Leaky Petcock + Leaky Float Valve(s) = Fuel in Engine Oil
THAT'S NOT GOOD... but at least it's easy to check whether the condition exists.
To check for this worst case scenario, begin by removing the fuel hose from the petcock with the petcock set to RES and, of course, the engine OFF. Aside from a momentary dribble from opening things up, there should be no fuel at all. If there is a continual flow of fuel, no matter how small, then you need to check further. Open the oil filler cap on the right side of the crankcase and stick your nose inside. If you smell fuel in the crankcase, it necessarily means that you have both a leaky petcock and at least one leaky float valve in one of the carburetors.
It happens surprisingly often - so often, in fact, that I now regularly remove the fuel hose from my petcock just to verify that my own petcock isn't leaking. I also smell the oil each time I do an oil/filter change. If you're unfortunate enough to find this condition, it means you'll have to repair your leaky petcock and you'll also have to remove the carburetors to fix the leaky float valve(s) at the very least. Both can be done at a reasonable cost and without too much difficulty (well, that's debatable).
The Solution: Petcock Replacement / Rebuild
All models of Maxim-X are equipped from the factory with a vacuum operated TAIYOGIKEN petcock which is identified in the Yamaha Parts Database as follows:
Fuel Cock Ass'y 1
Yamaha Part #: 31A-24500-02-00 Current
Yamaha Part #: 31A-24500-01-00 Superseded
Yamaha Par t#: 31A-24500-00-00 Superseded
Yamaha Part #: 1AA-24500-00-00 Superseded
If you're not comfortable trying to rebuild the petcock yourself, then the entire assembly can still be purchased directly from your nearest Yamaha dealer for as little as USD $56.91. However, you'll likely find that the Petcock Assembly is backordered as I discovered when I checked on October 23, 2006. Nevertheless, if you're determined to buy a complete unit, you can use the information in the table above to identify the assembly while standing at the parts counter or when asked by phone or e-mail.
If the price of a new Petcock Assembly is more than you're willing to spend but you're still determined to replace the unit as a whole, then you'll have to start checking used parts suppliers worldwide. When you do, it will be helpful to know all the Yamaha models which share the same Petcock Assembly. You'll find them all listed in the following table:
All Yamaha Models with Maxim-X Petcock
1983 XJ900RK Seca
1985 XJ700N Maxim (non-X, U.S.A.)
1985 XJ700NC Maxim (non-X, U.S.A., California)
1985 XJ700XN Maxim-X (U.S.A.)
1985 XJ700XNC Maxim-X (U.S.A, California)
1985 XJ750XN Maxim-X (Canada & International)
1986 XJ700S Maxim (non-X, U.S.A.)
1986 XJ700SC Maxim (non-X, U.S.A., California)
1986 XJ700XS Maxim-X (U.S.A.)
1986 XJ700XSC Maxim-X (U.S.A., California)
1986 XJ750XS Maxim-X (Canada & International)
I'm still working on the details of the petcock rebuild itself so you'll have to wait patiently for that to be posted. Meanwhile, I thought it important to at least post a description of the problem and how to identify whether you had it. I also thought it would be helpful to post petcock part numbers and other Yamaha models which use the same petcock in case someone reading this wanted to skip right to the replacement.
© 2004-2006 HP Software Productions
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Servicing the Petcock
The Petcock is quite simple in its construction and operation. A correctly operating petcock will only allow fuel to flow when vacuum is applied (small hose attached) no matter what position the petcock is in. The "Off" position will not allow fuel to pass even with vacuum. This allows removing most of the fuel from the bowls, if needed, by letting the bike burn it off while running. However, for storage purposes I’d go a step further and use the drain plug at the bottom of each bowl. My other bike does not have an "OFF" position but rather a "Prime" or always on position. All vacuum operated petcocks operate basically the same. PRI or Prime is used to refill the float bowls following servicing the carburetors.
Once you get the tank off set it down on something soft. Pickup the rear and roll it up on its nose. It will sit there and allow you to remove the petcock without spilling gas. However, when you set the tank back down flat hold your finger over the vent tube or gas will begin to siphon out.
Remove the petcock by loosening the flange nut. Carefully pull the petcock out. You’ll see the fuel screen attached, which is in two sections; one for "On" and the lower portion for "Res." To clean this part use basic carb cleaner or contact cleaner. Just be careful with the screen, its very delicate.
The rest of the petcock is made up of three sections. The 1st is the main unit which has the screen attached. The 2nd and 3rd pieces are attached to the main section with 4 Phillips screws. The outer section is just a cover. The middle section holds the diaphragm. Notice that this section has a small nipple protruding which has a hole in the center. This is a check valve. Remember which direction this is facing in relationship to the main section. There is a spring between the cover and diaphragm. This spring pushes the diaphragm back when vacuum is released and prevents fuel from flowing. Also note when you pull the cover off and remove the spring. The rubber diaphragm’s larger section faces outward.
Clean everything with your cleaner and reassemble. Make sure you VERY carefully pull the ends of the diaphragm up and clean behind and between the folds. If for any reason the middle section will not pull away from the main section DO NOT force it. It simply means your check valve is plugged and vacuum is holding it on. That’s why when you disconnected your fuel line, gas may have continued to flow until you turned your petcock to the "Off" position. Carefully lift up on the end of the diaphragm to release pressure.
Now that it is all back together. Its time to test it to ensure it works properly and won’t require pulling the tank back off later. Simply attach a clean rubber hose onto the vacuum nipple. Apply a slight vacuum to the hose while looking down the fuel outlet. Yes, your mouth works great for this. As you apply vacuum/suction you’ll see the diaphragm pull away from the main section. When you release vacuum/suction the diaphragm will SLOWLY return sealing off the flow of fuel. If it doesn’t, either you assembled incorrectly or your check valve is still clogged or defective. If all works, you’re done!
Courtesy of:
Chuck B
