Need info on gas engine problem. We can make it good on low and high but not both.At factory recomended settings it back fires at full throttle in the air and just pops on the ground. Could the problem be the ignition? We changed the plugs and this did not change anything. Thanks........ Kent

Hate to answer a question with a question but, do you really mean backfire, or are you hearing a burble?

Also, what brand/size prop? Hope you're not underpropped........

Assuming you're not, then....
If it's backfiring it can only be related to ignition, and most often ignition timing.
I suggest you check it, and perhaps retard it slightly.

If this doesn't work, then it's back to the distributor, unless you just simply want to replace the ignition module.

Good luck....

Hi
I had the same thing happen with my 100B2, the batteries were not fully charged.


Just a thought.


Bill

Just to add to what whidbey says, if this is indeed the root of your problem, low battery voltage can also be caused by using inadequate wiring gauge to power the ignition module.

How long's the lead from the switch/battery, and what's the gauge wire? Hope it's at least 22 gauge.

I have a 3W-75 that I just bought, and the same thing was happening to me, found the battery I was using was just about dead. Charged it up!! and WOW!! What an engine!!

Kent you realy should phone the dealer your bought that off of since if its new its warranttie.. sounds to me like the timing is off but better to call Gerhard or Bobby over it

Randy
DA true and blue