20 Most Recent Craftsman 25cc Gas Line Trimmer - Page 5 Questions & Answers

Go to Sears with the model number and they can order the parts for it. When they come in you should get a guide book that tells how to replace it. BE CAREFUL there is a large spring in there.

This is an ongoing issue for users, and rightfully so .On your machine.. Small diameter line out of fuel tank (has filter in-tank on end) connects to the side of the carburetor that has the fuel pump....that is the cover without the hole in it. Other larger diameter fuel line out of tank connects to the longer nipple on the external purge/primer bulb. The bulb "pulls" fresh fuel from the fuel tank to the carb and then out of the carb to itself, where it then pushes any air/old fuel back into the fuel tank. The remaining larger diameter fuel line in this setup goes from the metering chamber (has cover with writing on it and a vent-hole) side of the carburetor to the smaller nipple on the purge/primer bulb. Years ago on 2-stroke trimmers, primers were not even used,...you choked the carb with a slide lever and gravity let fuel enter the carb from above...a few pulls, a "pop"...slide it off of choke and away you went.
If the purge/primer bulb is on top of the carb...small line from carb body to small hole in tank with filter. Larger diameter line goes from the bulb on the fuel pump side of the carb to the larger hole in the fuel tank where the line is held in place with a nylon nipple connector that keeps the line from pulling out of the tank.

That's good ...most won't start...kill switch wire more then likly fell off or tab it connects to broke off...take outer housing off and look for any loose wires...

You need to clean the carburetor. Remove and disassemble carb. Use a den Tek Brush, (used to clean between teeth), to clean the small portals in carb. Use a carb. cleaner while cleaning. Make sure the small screen in carb. is free of debris. The smallest of paticles can cause the carb. not to run right. Reassemble the carb. and try starting. If there is no change, then you will need to buy a carb. kit for your trimmer. Replace all appropriateparts: gaskets, diaphragm, needle valve, and the small screen.

Jim

Cut the end of the line at a sharp angle. Spray WD-40 on the line and fuel tank hole. Slowly screw the line in the tank far enough so you can connect the fuel filter if you are replacing that line. If not just push the line into the tank if you have a two line system. Remember on the fuel primer, the long tip has the line going to the tank, and the short tip has the fuel line going to the carb.

Hi I have a craftsman 4 cycle model no. 316.791970 gas trimmer. When I pull on the rode there is little resistance . I took the sparkplug out and put a flash light down the hole and there is a thing that is moving . What should I look next, or do you know what is wrong? Thanks for any help! I've had it only 3 years and already Sears have replace the clutch assy.

I bought a Shakespeare Push-n-Load 3 blade trimmer head at The Home Depot for about 26 dollars and picked up a pack of 12 replacement blades for another 7. Did a whole 3 acres worth of weed whacking and still didn't need to change the blades. I was also powering through some pretty thick bushes with ease. Highly recommended.

The most probable problem is no fuel delivery to the engine.

1. Check/replace the fuel in-tank filter, you should be able to easily blow through it once removed. The primer bulb will sink down and not return quickly if the filter is bad. Fuel will not return to the tank via the return line if the fuel filter doesn't allow fuel to be pulled in.

2. If fuel is returning to the fuel tank when the primer is pushed then your problem is inside the carb.

3. To verify this put a small quantity of gas in the lid of a water bottle (half full). And pour it into the carb throat. Replace the air filter to prevent a backfire from shooting flames out. Try to start the weedwacker. If it runs and then dies the problem is inside the carb.

4. If you are really good at working on things with small parts you can clean out the carb and replace all of the gaskets to solve the problem. If this isn't for you then you should take it to a lawn shop and have them clean the carb and replace the gaskets.

NOTE: Replacing the gaskets is very important because the gaskets get stiff and the fuel pump action of one of the gaskets is reduced or stopped.

Hope this helps, Karl