I don't know how old the mower is but it has a 13.5 hp I/C gold 28R707 engine on it and a 42" deck. I found all the gas in the oil and filling the air intake below the air cleaner. I found the air cleaner had been leaking dirt into the intake. I took off the intake and cleaned it and the bowl changed the oil and also installed new fuel line, filter and added a fuel shutoff. All B&S parts. Now the engine doesn't want to start and backfires out the muffler. It seems like it isn't firing at all. I pulled and cleaned the plug and get fuel to the bowl. It does leak oil, I suspect it might be the filler tube, with oil and dirt on the wire loom that runs under the tube. I mow pretty much year round and it ran fine last year and up until this problem came up though it does blow smoke and uses a little oil.
Thanks for any ideas you may have.
Jerry

Try a new spark plug. You old one may just be gassed.

Ok I will. Thanks a lot for the reply.

Sorry about the delay. I've been out of town. I changed the plug and it still won't fire.

Is the spark plug wet with gas? Is it firing? Did you take the flywheel off or loose? Does it have good compression?

Things have really been hectic around here the last few weeks and this project took a backseat. I am really sorry I didn't get back to you quite a lot sooner.
This morning I did take the flywheel cover off and found the Key broken and slipped about 1/4 around so when I get a chance I'll fix it but thank you for your help on this.

 

Aw crap... I tried merging the new post with the old thread and hit the wrong button. Unfortunately, there is no "undo button".

 

The original post here is a merge of 6 posts, which is why it doesn't make sense. The first part was posted by GerBa76 in july.

The first reply is from 38racing.
The next 2 lines are replies back from GerBa76
The comment about the flywheel was from myself
The final comment was from GerBa76 again.

The final comment was posted in a new thread by itself today and I attempted miserably to combine both threads in a comprehensible manner.

 

Fixed the key, put everything back together, sprayed some fuel in the plug hole and it fired right up. While I had the head off checking the valves I cleaned quite a bit of carbon build up from them and the head so it actually runs better than it did. Thanks for your help on this project and my hip thanks you too since I don't have to mow with the walk behind any more.

 

Great! Glad to help!
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