Craftsman one-pull start mower takes 10 pulls to start!

Hi, Great forums! Last year I inherited a Craftsman 6.0 hp lawnmower from my in-laws. They gave up on it because it takes SO much effort to get it started initially at cold start-up. The mower is only a few years old and says "One-Pull Start" right on the engine. Well, I have a hard time starting it as well and the other day finally broke the pull cord. The cord I will replace but can anyone please offer some suggestions to me as to what may be the problem with the engine. Once it is started for the first time it runs great. It will start up on one pull on every subsequent time after its been running(i.e.-after emptying the bag, etc.). This did not just start happening. It has been happening since they bought it. They took it back to Sears and of course it started first time for the guy there. I take very good care of my mowers, changing/checking the oil, blade sharpening, etc. I am also very mechanically inclined as well and would like to try and fix this myself. Thanks in advance.

John

 

Most likely, this engine has a primer bulb. Sometimes you got to press it many times before it will start on one pull. I find the best way to know how many times to pump the primer is buy getting youself down there, put your ear next to it and prime it till you here liquid being pumped.

 

You didn't mention which engine you have, but I'll guess you have a Tecumseh. Tecumseh's are very finicky when it comes to priming procedure. Using your thumb and pushing squarely, push the bulb in (with decent pressure to ensure good results), keeping it in for one second, release for one second. Repeat this for a total of five primes, using this slow and distinct procedure. See what happens and let us know.

 

Thanks for the reply. I am a dope for not knowing what engine it has , but I swear its a B & S. I'll post it when I get home from work tonight. And I'm pretty sure that its a problem with something and not just a failure to follow the correct priming procedures. I have tried many different primings to see if that helps. Just above the priming bulb it says 5 times. I have tried that, 3,4,6,7,8,9,10, etc and nothing makes any difference. It does seem, however, that maybe the priming bulb is not working correctly. It almost doesn't seem to push in correctly. Like the bulb is not releasing any of its air. Any other thoughts?

 

AH, your last post tells me you may have to possibly clean the inside of your carb. It would be very helpful to get those numbers because we don't know if you have a bowl carb or a diaphram carb. Thanks...

 

Again, thanks for the replies guys. Appreciate it. I can't seem to find the exact mower doing an internet search. The model number I wrote down from the back of the mower seems diff than the numbers listed at Sears' and other websites. I'll check it out later and post tonight.

 

OK, its A Techumsa model 143.996510 engine. 6.5 HP

I also remembered that there is a tube/line that goes to the side of where the primer bulb is that appears to be cracked. Could that be causing the problem?

 

The cracked tube you're referring to is the crankcase breather tube. This, directly, won't affect starting. However, this will allow contaminents to enter the carburetor as there is a vacuum associated with such. You likely have restriction in your carburetor requiring removal of such to clean and recondition. Are you willing to do this? Have you ever disasembled a carburetor before? It's not for the faint of heart, but not necessarily impossible for a first-timer. Let us know.

 

Hello john!

I agree...

Most of the time, just cleaning the fuel bowl screw will solve this problem. Remove the screw/bolt that holds the carburetor bowl on. (it is a brass bolt with a 1/2" head on the bottom of the carb). In it are 4 holes. There are 2 holes that oppose each other near the base or head of the bolt. There is also one that runs down the center of the bolt. Then, near the end, in an unthreaded section, there is a very tiny hole that can be hard to see, especially if it is clogged. Use a stiff wire, or preferrably a torch tip cleaner (available at welding supply stores and large home improvement stores for around $5.00) and clean these holes out. Let us know how it goes!

 

Thanks again guys. I am going to pull the bowl off as you said and clean it up with some carb cleaner and a piece of wire. I have no problem taking apart a carbuerator and cleaning it. Have rebuilt carbs on cars many times. I replaced that tube, so thats ok. Just have to find a new pull cord now and a retractor assembly which doesn't seem to have any spring in it anymore. Sears didn't have one. Just a cheap cord. Anyone have any good online sources for factory replacement parts for Craftsman mowers? I also noticed what is most likely my starting problem. The primer bulb was ripped underneath. I pulled that off and will replace that also. Is that my problem would you say?

 

It wasn't helping matters, for sure. Whether it was the entire problem or not, you'll soon find out! Let us know how it goes!

 

OK, well I found the owners manual finally. Looked around on the internet for an hour for a source for the correct replacement parts(Recoil starter and primer bulb) and couldn't find the right part numbers. Called the Sears parts number and ordered them there. Gonna pull the fuel bowl off and clean it when the parts come in and I'll let you know how it starts afterwards. Thanks for the replies.

 

Just wanted to post my results and thank you guys for the help. Got my parts in last week. Replaced the recoil starter assembly, spark plug, air filter, breather tube hose and primer bulb. Also pulled the carb off and cleaned it out thoroughly with carb cleaner, filled it with fresh fuel, sharpened the blade, changed the oil and cleaned the deck. Worried me for a few minutes as it took about 15 pulls to finally get it started, but after that it started on every pull. Have used it twice since and it starts up on the first pull EVERY time. Runs like brand new now. Thanks for the help.

John

 

Good news! Glad we could help. Anything else, you know where to find us.

 

Good Job! Thanks for letting us know the outcome!

 

Hi,
I have exactly the same lawn mower, and had exactly the same problem.

While John has solved his problem, he replaced many parts, so I thought I would add some info for the sake of others that may experience the same problem in the future.

The primer bulb is connected in this mower to a tube that transfers the pressurized air to where it actually pushes the gas. The tube was originally manufactured from defective material, and tends to collapse, preventing the transfer of pressure.

I opened the tube, and everything worked great for about a week... then it collapsed again.

The solution is to replace this tube, or alternatively, simply use the priming bulb in a different way. You have to push on it longer, holding it a bit, and listen. Keep doing it until you start hearing the gas actually moving. Once you get used to it, it only takes a few more seconds, and the mower will start of the first attempt. Of course, if you don't mind opening it up, it is best to replace that tube.

Ron