OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Trimmers and Brushcutters Two Stroke Trimmers & Brushcutters Talon Farm Hawk whipper snipper

My son gave me his old talon. It kicks for a second or two with a squirt of aerostart but stops when that runs out. I went to the mower shop for a carby kit but there are none. They said they replace the whole carburetor (I think $50). I have pulled the carby apart and cleaned everything but still won't go. It won't suck fuel from the tank. Are there any compatible brands, that I can use that have a better carby? By the way there are heaps of Talons out at the council tip shop but I am a bit concerned they may have the same fault.

It seems to me the best way to answer your questions is to find out what is wrong with your machine.
First, I recommend that you stop using aerostart. It does not do much of a job of starting engines, but does a better one of washing the oil film off the moving parts inside. Try removing the air cleaner temporarily and squirting a small amount of 2-stroke fuel into the carburetor air intake, instead. Keep clear of the carburetor when you try to start it, of course - without the air cleaner it is possible for the engine to spit back.
Since it obviously has spark and at least some compression, there are five main issues that might be making it hard to start. The first is improper starting procedure. The second is a deteriorated spark plug. The third is lack of fuel delivery to the carburetor. The fourth is a problem with the carburetor's fuel pump. The fifth is amateur interference with the carburetor's mixture adjustments.
1. If you have the machine's operator's manual, follow that precisely when you try to start it.
2. If it has had the same spark plug for years, that will be at least part of the problem.
3. The fuel tank will only allow fuel to exit if air can enter to replace it, and if the pickup device in the tank is working properly. This involves air entering the tank either by a vent in the tank cap, or a vent line into the tank, plus a fuel pickup and filter device in the tank interior, a fuel suction line from the pickup to the outside of the tank, a fitting where the fuel line exits the tank, and another fuel line from there to the carburetor. All of these can and do malfuction for various reasons.
4. The engine relies on a fuel pump which is built into the carburetor, and operated by a pulse line connected to the engine crankcase. Sometimes that line is internal to the engine and connected directly to the carburetor, and other times it is a second rubber hose connected to the outside of the carburetor. This pulse system is prone to getting crudded up with black engine goo and ceasing to transmit pulses. The fuel pump itself is even more prone to giving trouble if it is left for years with fuel in it without being used. The fuel is likely to have turned to jelly, gumming up the pump completely.
5. There is a tendency for people who are having difficulty starting a small petrol engine to fiddle with the two mixture controls (idle and high speed) on the carburetor. Once they have done this, the engine will not start or run until the adjustments are reset to where they were in the first place.

We can work through these five possibilities if you want, but we would all have to know a number of details about your machine: what kind of fuel tank and feed it has, what brand and model of carburetor, etc.

Thanks Grumpy. I'll put up some pictures of the snipper and the carby. I've already done some of the things you mentioned. New fuel, filter, spark plug, there are no external adjustments on the carby; It is all pre-set. the only adjustment is a throttle speed screw to move the throttle cable back and forth slightly. I will have closer look at the fuel tank and cap. As to brand...well I can't see any markings on it and when I showed it to the lawnmower shop they said it is a throwaway job. I'll get the pictures up today.

Sometimes there are simple clues available. I bought one a few months ago that hadn't been run in years. The only problem aside from a timed-out spark plug (which made it hard to start, but not impossible) was a stuck vent in the fuel tank cap. There was an obvious clue: when I pulled the starter, bubbles passed back up the fuel line from carburetor to tank. I just had to unstick the cap vent, and install a new spark plug, and it was good to go.
Lack of tank venting usually results in start-and-stop problems (runs for 15 seconds then stops) rather than no start. A split in-tank fuel pickup hose, or a blocked pickup filter, on the other hand, means no start.
There is a reasonable chance the fuel pump pulse chamber of the carburetor is full of jelly. Also, if it does not have an in-tank pickup filter, the filter gauze in the pump chamber may be puttied up with dirt. However you should check the simple external things before we get to that, and we need to identify the carburetor type before we talk about the fuel pump. BTW, the jelly-in-the-pump problem is quite likely to cure itself: the jelly is soluble in fuel, so if you get it feeding even a little bit if fuel it will recover by itself.
The main thing is, since you have spark and compression, and you seem to have access to plenty of fuel system parts from junked machines of the same type, this should be fixable without very much drama.

I hope these images work. I've had the carby apart many times to clean jets. The fuel lines from the tank may not be fitting very well but in any event it won't suck up fuel. I squirted some fuel into the carby and it did run for a little while (enough to make me think it was fixed) and then it died.

another possibility is the fine gauze filter in the carby its self. a very common problem with ryobi ect units of an age. they appear to be clean on inspection but because they are so fine its hard to tell with the naked eye. try removing it and lightly blowing all the passages, but be careful as there is a small brass jet that can easily be dislodged and lost.
regards jay

If it ran for a while it may be that there was jellied petrol in the pump, and it is dissolving. So long as you are using mower fuel to prime it, you will not hurt anything so a couple of repeats of the prime-and-run-until-it-stops trick should do no harm. If it runs longer each time, you are clearing the problem.

While the pulse hose (the other one entering the carburetor) is off, pull the starter and see if the hose pulses air in and out. If it does, it isn't blocked.

If you want to you can check the fuel pump chamber, and the pump intake filter, by removing the four screws holding the black cover beside the fuel line from the tank. That will expose the filter if it has one, and underneath it, the pump diaphragm. If you decide to take it apart, clean the gauze filter with petrol then blow through it, and check that the chamber is clear (no jellied petrol). However I would not do this unless the prime-and-run process does not help. It disturbs the diaphragm unnecessarily, and if there is a filter on the in-tank fuel pickup there should not be dirt on the pump intake filter.

I think I need to get some new fuel line too. It might be losing vacuam there. If I have to, would any other carburretor from a whipper snipper work?

If it physically fits your intake pipe flange, doesn't foul on any other hardware, and you can conveniently fit the throttle cable, it will work within limits. Because your carburetor has fixed tuning, you cannot adjust the mixture of a different carburetor to suit the peculiarities of your engine. This may be a problem. The other main limitation is that if you have a small engine, you need a small carburetor or your throttle will only be effective for a tiny, initial part of its movement.

the one thing i have found with these type carby is that they are very hard to fit other types to because of the throttle mechanism. Honda and many others used the walbro equivalent that were fixed inlet too, and i personalty hate them. i have replaced them by changing the whole throttle linkage but its hard unless you have plenty of bits to make it work (thats what years of junk collecting do)
regards jay

Your problem is the tank most likely because on all tanks you should get fuel just coming out the fuel line when the petrol cap is secured. All you need to do is close off the return line and see if fuel comes out the pickup line.

Note that the carby will not suck fuel when dry and that is what happens when you don't get fuel coming up the line. The tank should build up pressure to push the fuel up the line and I notice in the picture the tank has been damaged at some time.

I would be replacing the tank first then look at the carby. It appears you have put the cart before the horse and that really does not work.

Well that is interesting. The tank had a hole in it and there is some gunk all over the tank that was use to repair it. The repair looks OK though. The cap will not allow air through it. The seal at the tank for the fuel lines is good. There is no primer bulb (though it wasn't working when there was one). I am off to the mower shop for new fuel lines and primer bulb. The tip is closed until Thursday so I can't get a fuel tank or carby.

I've just tested the tank (Geez, fuel tastes awful) and there is a leak in it. I feel like breaking into the tip to get one of those damn tanks!

Why not wait until Thursday then replace the whole fuel system? Once you have a decent-looking original-design tank and fuel lines, plus a primer that works, it will be time to talk about the carburetor if you still have a problem. As long as you have a busted tank, loose fuel lines and no primer, there are too many problem areas for a diagnostic process to work sensibly.

At the tip you should be able to buy a whole machine for less than 5 bucks, then just buy some fuel line and primer parts.

I've got the fuel line and primer bulb (fuel line was $2.40 per FOOT!!-I'd almost forgotten what a foot was). Sadly I have to go to work tomorrow and that means leaving town for the next eight days. When I'm back the following Thursday I will get the tank - I tried repatching it and there is fuel to the carburettor now but not a lot of improvement. If I can get a wrecked machine I'll also try its carby. Thanks for everybody's input. Stay tuned for the next episode.

I am back. I couldn't wait for next thursday so last wednesday I called into another mower shop and asked if they had an old carby. As soon as he heard it was a Talon he had a pained expression and said,"They're not much good". Anyway he sold me a used carby for $20 and if I wanted the fuel tank it would be extra. I took it home and swapped them over. It ran like a demon on the third pull...FIXED!!
I got curious as to why the old carby wouldn't work so I pulled both apart. The words of Grumpy soon came to mind "but be careful as there is a small brass jet that can easily be dislodged and lost". Somewhere in my garage it lies, undisturbed, mocking me forever.
Thank you to all who helped.

It was mowernut who warned you about the jet falling out.

Glad you've got it fixed. I'll close this thread.