'01 challenger (twin 720 rotax) dies at wot

[timh1025]

One engine runs fine. The other dies, only at or near wot. It'll start back up almost immediately.

Tried fresh plugs and checked the filters by the fuel tank while I was still in the water. I've since flushed the fuel and return line from that engine, but found nothing much. I doubt I have more than 100 hours on these engines.

I'm a decent shadetree mech. when it comes to cars, but very limited on the rotax. I'm willing to learn (read "too poor to hire a professional"). Any advice would be helpful. Thanks Tim

[Technical Support]

Most likely you need to rebuild the carbs. Swapping the racks will confirm.

[timh1025]

Thanks for the quick response. That second engine may pay for itself just for the part swapping option. [img]/graemlins/winkanim.gif[/img]

[Bill O'Neal]

The internal fuel filters inside the carbs are probably clogged up.

[timh1025]

Still having a problem with the port engine. The carb swap between engines didn't change anything. I guess I'll swap coils/ignition parts next. Any ideas?

[Colin GSXL]

When it dies does it stop suddenly or splutter to a stop. Just wondered if it's seizing up? Have you looked at the plugs immediately after it dies?

[timh1025]

It looses rpm's gradually over about a 4 second interval until it gets down under about 5000, then dies completely. I didn't restart the engine on the last run, but haven't looked at the plugs. I'm fearing the worst.

[Technical Support]

That really sounds like a seizure...definitely do a compression test.