83 Ezgo, Freshly rebuilt engine, getting fuel & spark, but won't fire up. Help?

[Plumbergs]

Me again, back for more help from the experts.

Got the freshly rebuilt 2PG back in my cart yesterday, and it still won't even try to crank. Here's all the details to help with the diagnosis..

1) Like I said, the engine has been compltely rebuilt.. New crank, seals, piston, cylinder, the whole 9 yards.

2) I haven't checked the compression yet (I have to borrow a tester and check it tomorrow) but I believe its fine because I took out the plug and tried putting my finger over the hole while cranking the engine.. I couldn't keep my finger over the hole, so I'm thinking the compression is fine. I'll test and post the actual numbers soon.

3) Its getting a good stream of fuel from the fuel pump. I recorded a short video so that you can see for yourself:
Click here to watch the video

4) I even took off the carb and tried spraying fuel directly into the elbow above the reed valve. Also took out the plug and sprayed a little fuel in the cylinder. Nothing.. Not even a backfire.

5) The plug is firing.

6) I checked the reed valve.. Its installed properly and looks fine.

7) At first I thought maybe it could be the timing.. But I know I put the pulsar in the proper position.. Plus if it were the timing, I should still get a backfire or something. I'm not getting anything. Its not trying to fire at all.

8 ) Muffler has been BBQ'd and isn't clogged.

I know the engine needs 3 things to run.. Fuel, Air and Spark.

*Fuel - I believe I've eliminated this one as being the culprit because like I said, I sprayed some directly into the cylinder.

* Air - I think this one is eliminated as well because I checked the reed valve (its fine), no obstructions on the intake side, compression is good, and the muffler was just BBQ'd.

*Spark - I pulled the plug out of the head and held it against the block while turning the engine over. It was firing. Tried two different plugs. One plug was firing a blue spark and the other was orange. (I know blue = better).

The only thing I can think of is that even though the plug is firing, maybe its not getting enough spark to ignite the fuel?

What do you guys think? Suggestions?

[Dave Box]

Are you starting with a brand new spark plug? The reason I ask is that I have seen plugs that fire when not under compression i.e. out of the cylinder but fail in the engine. This seems to be more prevalent on 2 strokes. If you are putting fuel directly into the cylinder then, as you say you should at least get a backfire.

Dave

[Plumbergs]

Originally Posted by Dave Box

Are you starting with a brand new spark plug? The reason I ask is that I have seen plugs that fire when not under compression i.e. out of the cylinder but fail in the engine. This seems to be more prevalent on 2 strokes. If you are putting fuel directly into the cylinder then, as you say you should at least get a backfire.

Dave

Ok, that makes sense. I'll grab a new plug today and report back tomorrow. Thanks Dave!

[Plumbergs]

Dave,
It turned out to be a bad plug wire.. I substituted the wire from my John Deere 314 and it fired right up!

[madoc1]

way to go plum! be sure to run the fist tank at 40/1, then switch to 128/1. let us know how it performs. now you are the new expert.

[Dave Box]

Well done Plumberg you have earned your chops and are now a maven amongst men.

Dave

[Plumbergs]

Thanks Madoc & Dave. Like I said in the build thread, I couldn't have done it without you guys.