Export thread

I recently inherited a craftsman mower that was not working. I used to use it as a kid so I knew what was actually wrong with it, or so I thought. Got everything running fine and then after 5 minutes of running it died.

Model: Briggs n Stratton 31P7770296E1


So first things first.
New spark plug
new air filter
Break is down
Seat sat on
Neutral

The flywheel is spinning and gas makes it to the float bowl. However I don't know if it is making it up into the carb and towards the spark. I just got a brand new carb because I found out the last one had a crack in it (wasn't all the way through) so i figured might as well replace it now. When I crack the hose to the carb gas flows freely and as I said it makes it to the float bowl (I need hear the needle click) but I don't think it is going upwards.

I put some fuel stabilizer in there so i was wondering if maybe I made the gas too rich. However, before I drain it and put new gas I would like to know, how can I check to make sure gas is making it to the spark rather than just assuming it isn't and buying new gas.

Spray some starter fluid, (ether) into the carb... if it starts, you have a fuel delivery problem.
If it will not start, then you have another problem... :smile:KennyV

It looks like I have another problem then

I can't seem to figure out what to do next.

Remove the spark plug then while holding it against the engine, with the wire attached, see if you have a good spark... :smile:KennyV

It does indeed spark.

This is a long shot, but years ago I had a Craftsman self propelled mower with a similar problem. It was getting gas & spark, but would not fire. It ended up being the flywheel key had broken and so the timing was off. A new flywheel key and I was off and running. I'm not sure what caused it, but I think my son hit something in the yard.
Bruce

After tinkering with the engine some more I FINALLY found a big problem...

I took off the cylinder head and noticed there were 2 spring like objects in it (after some oil drained out). One of the nuts to connect the "spring" and a rod was completely taken off. I screwed it on a bit and tried to start it, I got SOME firing YAY. I didn't try to actually start it, but I did hear something. So before I actually started it I looked something up about it and found out there needs to be some proper settings to it or else it will tear up the engine.


So this is where I'm needed help now. What adjustments do I need to make or try to make.

Kamori said:

After tinkering with the engine some more I FINALLY found a big problem...

I took off the cylinder head and noticed there were 2 spring like objects in it (after some oil drained out). One of the nuts to connect the "spring" and a rod was completely taken off. I screwed it on a bit and tried to start it, I got SOME firing YAY. I didn't try to actually start it, but I did hear something. So before I actually started it I looked something up about it and found out there needs to be some proper settings to it or else it will tear up the engine.


So this is where I'm needed help now. What adjustments do I need to make or try to make.

Click to expand...

You need to remove the spark plug and rotate the engine until it is at TDC on the compression stroke. At this point the valves can be set using a feeler guage. Both valves can be set at .005 and she'll run fine.