Some engines utilize a manual fuel primer bulb to enrich the ratio of fuel in the fuel air mixture for initial engine starting. Just a heads up. The most common source for an air leak is the water separator. Going backwards like that would require source of gas to be from "vent" line in tank which isn't low enough into tank and would not be filtered. The air bubbles can be coming from a leaking high speed check valve and dipping a carburetor can destroy these check valves. Get more answers from the people in your networks. And when you squeeze the bulb are you holding it in a vertical position with the intake at the bottom? Definitely pulls from carb side and pushes into tank side which makes no sense to me at all. it could be a slight crack or weathering in the bulb or the hose. A couple of other thoughts. Hold the primer bulb vertically with the arrow facing the sky and squeeze the primer bulb until … How to Troubleshoot a Primer Bulb. Curious question, Does the chainsaw have a primer bulb? the primer bulb was staying half full of air so i thought the primer was bad. Step 1. At full throttle everything was fine but as soon as you let off it would often stop dead. Ok I have a stihl 041 farm boss that I have been working on. You should have fuel in the bulb when running. 4. Why? I DRAINED THE FUEL TANK AND PULLED THE PICKUP OUT.LITTLE DID I KNOW THE OLD ORIGINAL CLUNKER HAD BROKEN FREE FROM THE BOTTOM AND COVERED WITH STICKY VARNISHED FUEL.NOTICING THE CURRENT PICKUP WAS SMALLER I THOUGHT I'LL PUT THE CORRECT PICKUP IN AND PROBLEM FIXED(AIR BUBBLES IN FUEL TANK) I CUT SOME WOOD,SAW STOPPED,TOOK OFF THE CAP, FUEL WAS BUBBLING,PULLED THE PICKUP OUT,FUEL STILL BUBBLING,FUEL WARM BUT NOT HOT.DO THE SXL 925'S HAVE FUEL RETURN LINES, CRANKCASE CHECK VALVES? it has to do with vapor pressure,down stream of the priming bulb there is vacuum,right ? New lines, primer bulb,fuel filter and a rebuild kit did nothing. Clean the carburetor and primer bulb components. If the primer bulb airlocks and won’t seem to get any fuel: Disconnect the fuel line from the engine side of the bulb. They are due to fuel vapourising in the line due to ambient temperature. It is essentially not seating and drawing air in through the discharge port. 5. A prime example is a vehicle that was in our shop and the painter was getting ready to put primer on a … Atmospheric pressure in the tank through the vent pushes the fuel from the tank to the engine. If not try it that way. Check that the filter's in place and in good condition. If … We are more concerned of a car paint bubble as it pertains to a refinish process. House of Homelite Hardware Store - List part you have or find something you need to keep the Homelites running. the only way i could see bubbles forming inside the bulb is due to an air leak from somewhere, only 2 places really... the seal/gasket on the carb where the bulb sits or the actual fuel line.. if there was a leak in the normal gaskets where you fix it to your engine then i dont think that would cause it, all that would do is make tuning difficult & your engine run cack ? Then there is the other style that is a little more complex but works on the same principle as the Purge Primer. Blower, lawn mower, weed eater, trimmer Pushing on primer bulb PUSHES air OUT of fuel filter and sucks from carb side of bulb. Everything looks good and clean and it is only two years old. Pushing on primer bulb PUSHES air OUT of fuel filter and sucks from carb side of bulb. Formation of air bubbles (foaming) and resulting small, round concave depressions (cratering) when bubbles break in a paint film during drying. Nothing goes into the venture so you cannot flood the unit. Check valves are non-serviceable and replacement of the valve body is the only fix. Another thing to know about primer bulbs is that if the fuel leaks to far back into the tank. A result of surface tension. Nothing goes into the venture so you cannot flood the unit. Painting a vehicle with too much moisture in the air lines will create a problem. I have a stihl fs45 trimmer. When the outboard is running normally, the engine’s fuel pumps create a slight vacuum in the fuel hose. Remove the filter and repeat the test. Both the manual choke system and the manual primer system engines may experience this similar symptom of running only when the fuel mixture is enriched. For the T242, the primer bulb can be pressed into place in the mount plate from which the old bulb came. It has a new fuel lines from the tank to carb and inside the tank. I don't think the primer bulb itself is what's causing it to die, but may be a … If you do not, the check valve in the primer is bad. Super 2, and (1st, 2nd, 3rd, 4th, 5th, 6th & 7th) fleet of 330's. Your question was published, help is on its way! You could be sucking air - check the o-rings in the connectors. POSSIBLE CAUSE. Re: Primer ball won't get hard. It has a new fuel lines from the tank to carb and inside the tank. Eventually the air bubbles turn into a big gap of air filling up half of the fuel line and thus killing the motor due to lack of fuel. Click here to remove banner ads from this forum. Tiny bubbles that are uniform across the panel: these types of bubbles most likely are caused by moisture in the paint process. Inspect the carburetor bulb for cracks on its face. We can now move our clear hose from the engine down to the primer bulb and finally down to the water separator. pumped it up and it was good the rest of the day. Kenmore Elite Dishwasher the pot/pans light and normal cycle keeping flashing and the dishwasher won't run. A clogged filter could cause bubbles … There are bubbles in the tank when I push the primer bulb and, when the tank is full, some gas comes out of the tank at the cap. They are similar mechanically and this information would likely apply to your unit. The fuel line is clear, so I can watch the gas being pumped. Marketing, Service and other neat Homelite pictures. Check the Primer Bulb for Holes. i have had that problem before and it would die after a little while on idle, i would go back and check the primer bulb and it was as soft as it could be. When I hit the primer bulb, I paid attention to the bubbles, and confirmed that the bubbles are actually going out of the return line, which I assume is correct. Pulled out primer bulb and verified action separately. Just remember: your boat may have these components in a different order. I found the primer bulb was the problem the check valve inside must have been broken. Install the new primer bulb. – … Going backwards like that would require source of gas to be from "vent" line in tank which isn't low enough into tank and would not be filtered. NO DOES NOT HAVE A PRIMER BULB.AFTER READING A FEW POSTS ON THE PROBLEM,IT SEEMS THAT THE FUEL IS GETTING HOT ENOUGH TO BOIL,MAIN REASON BEING, NEEDS CLEANING BETWEEN ENGINE AND GAS TANK,AND A FEW OTHER THINGS CAN CAUSE THIS TO OCCUR AS WELL.LET YA KNOW HOW IT GOES. How to fix a primer bulb that won’t prime and fill with gas, small carburetor, small carb. Holes or splits can eventually form in the primer bulb. the bulb sounded like it was *** air. Faulty Primer Bulb Another cause of the primer's filling problem could be the bulb itself. i would check that first then try some differnt fuel. Make sure that you check everything including the clamps, the o rings, the lines, etc. Getting Started and Common Tasks for Creating Posts, Dressing things up with tags and pictures, Homelite Chainsaw Posts By Saw Family & General Repair Discussions, Pistons, Cylinders, Crankshaft, Bearings, Seals, The Cutting End - Bars, Chains & Sharpening, Homelite/Fisher Pierce/Bearcat Outboard Motors. Without the primer bulb, the starter cord would have to be pulled loads of times before the fuel lines and carburetor fill up. Thank you for the question on bubbles in the primer bulb. The air has to be being drawn into the line if you're seeing it, presumably from the top unless things are completely clogged there and it's drawing backward... Clogged carb would mean you weren't drawing gas, not that you'd be drawing air into that line... Do the bubbles move in the gas line at all? Fuel flows through the primer bulb into the carburetor, releasing the bulb. If it does have a primer bulb, I would replace it. Ok I have a stihl 041 farm boss that I have been working on. If so its possible that the check valve in the primer bulb is bad, and the return from the primer bulb is creating the bubbles. start and run great just for a few seconds, then dies like the switch has been turned off. But a bubble rusting from the exposed area or from underneath is fairly evident and self explanatory. Gasping for Air Priming begins with air pressure caused by pushing air out of the primer bulb into the fuel tank. If not try it that way. Thank you for the question on bubbles in the primer bulb. I would suggest that you start at the fuel tank and work your way to the carburetor. Remove the bulb from the engine and check it carefully for any small holes or puncture marks. As the moisture gets trapped under drying paint it will come to the surface within a short period of time, a few weeks or longer. And when you squeeze the bulb are you holding it in a vertical position with the intake at the bottom? It also has a new impulse line. Also a Homelite 20AV & 150 auto. Water separators get dirty and can create a … However if the arch is too large a vapour lock can occur. The first problem (bubbles in return stream) is a pain, but the second is a disaster for your pool, expensive, and may cause issues that will require the attention of a pool professional. When operating the primer bulb you could keep pumping without it becoming full and air bubbles were visible in the bulb. Craftsman Lawn tractor. I have painted a few cars in the past with nice results. I think you have the to fuel lines backwards on the primer bulb. Small perforations on the rubber could inject enough air into the fuel system to make the suction too weak. Review these links while waiting for an expert response. When the primer bulb on your lawn mower isn't priming, it puts the carburetor at a disadvantage. Some of the new trimmers have colored limiter caps on the low and high speed jets. I hope this helps you and have a nice day. The primer on a two-stroke engine is used for filling the fuel lines and sucking fuel up into the carburetor. A plugged fuel filter can do the same. I have changed oil, spark ... Toe out problem with Sears Garden Tractor mod. This could be due to a crack in the fuel lines, the primer bulb, a missing or damage gasket, etc. The primer bulb can’t suck it up without removing it. – … Runs for about 20 minutes and then stops running. Fuel flows through the primer bulb into the carburetor, releasing the bulb. It also has a new impulse line. Then you may also have to adjust the carburetor after changing the lines around. Most problems ultimately prove to be an air leak usually from a … With the arrow pointing to the side where you pulled the hose off. Fuel Line Problems Squeeze bulbs have a check valve at both ends that allows fuel to only flow in one direction--from the tank to the engine. No gas appears in the bulb when I prime it and, obviously, it wont start. The bubbles should make it sputter. one thing to check would be your primer ball. It is essentially not seating and drawing air in through the discharge port. When I removed it and pluged the suction side and pumped it. I installed a new primer bulb and also put new gas lines on. This time I ended up with tiny air bubbles all in the paint. You could be sucking air - check the o-rings in the connectors. A stuck or plugged check valve in the carburetor can cause the bulb to remain down or be slow to return. Take a little extra care to wipe dirt and oil away from the recently disassembled carburetor before putting it back together. Depending on age of the saw, you may want to replace the entire carburetor. Shaking a partially filled can of paint or using too high of a speed when using a drill mixer. Please Login or Register. You should have fuel in the bulb when running. I told this to a shop and they thought that maybe they were reversed. After it cool for 20 minutes it starts again. Gasping for Air Priming begins with air pressure caused by pushing air out of the primer bulb into the fuel tank. If it does have a primer bulb, I would replace it. Otherwise, there's no way but a failed line for air to get in. Then there is the other style that is a little more complex but works on the same principle as the Purge Primer. On any line older than 5 years, the sun causes the bulb, rubber end connector inserts, and fuel line to age, shrink, harden and crack, leading to tiny air leaks that prevent the fuel pump from pulling gas into the motor, especially at idle. A cracked carburetor bulb will not be able to create a vacuum and will prevent it … Then the finish was JAU Acrylic Urethane. Welcome Guest. Little bubbles in the fuel line from the carburetor to the primer should not prevent the engine from starting, but if the check valve will not seal when the engine is running, that could cause an issue. Quick fix: put some grease on the end fittings at the tank and motor. I sanded off the factory primer and used Shop-Line JP375 as the new primer. and Petrol is very volatile (BTW its Petrol not Gasoline) bubbled form cause u r sucking the fuel and causing it to go through a restricted orifice the NRV non return valve. A good tank filter should work to avoid including air bubbles in teh fuel supply till the tank is drained. I replace it and the truck starts and run great … If you do not, the check valve in the primer is bad. Have taken it apart. 917.28842, How do you change the Drive belt for the Sears tractor. The fuel line is clear, so I can watch the gas being pumped. I did some research in regards to high RPM on a weed whacker and could only find like situations with lawn mowers. Pulled out primer bulb and verified action separately. If I squeeze the bulb a few times it will clear the air out and will be full of fuel all through the line, then it starts all over again filling with air. All my engines have used an arched fuel line approach to the carb without problem. Definitely pulls from carb side and pushes into tank side which makes no sense to me at all. Customer: there was a lot of air bubbles in the bulb when i could keep it … Gas flows through the lines. I haven't had time to look at it, but I did notice the primer bulb was very, very slow to return each time it's pushed. The air has to be being drawn into the line if you're seeing it, presumably from the top unless things are completely clogged there and it's drawing backward... Clogged carb would mean you weren't drawing gas, not that you'd be drawing air into that line... 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