2 replies to this topic

[slngsht]

Hi, I recently bought a speedster 150 with twin Rotax 110's.

It ran perfectly for an hour or so. would top out around 52 or 53 mph. Then the left jet drive started squealing. Took it to a shop, which replaced the left jet drive... apparently it was completely out of oil.

When they test drove it, they said it had a hesitation on the right engine (something I did not experience when I ran it for that hour). They cleaned carb, replaced plugs and fuel filter, with no change, and had no idea what to do next, so I asked them to stop working on it, and picked up the boat.

Took it for a test drive last weekend, and I wouldn't exactly describe it as hesitation. The boat takes off OK, both motors climb up just past 7K, boat planes fine, then the right motor just backs down to about 4.5 to 5k for a couple of seconds, then accelerates to 7K again... stays for a couple of seconds, then drops again, picks up again, etc... Every time this happens, I have to correct with the steering, because right side power drops. While this is going on, the boat is going about mid 40's in speed. speed drops when right engine drops, and picks back up when I get power again. It does feel like it would climb into the 50s if the right motor stays at full speed.

Neither the drop nor the acceleration is sudden. It does so very smoothly.

I think I detect slightly rough running out of the right engine at part throttle, and it is just a bit harder to start than the left engine... but it does seem to run ok in general.

Any help to point me in the right direction is appreciated.

[Kevin Leclair]

Have you checked the engine compression?

[bryckhaus]

Your RAVE valves might be dirty and getting stuck. Its a problem I had this season. it would not go over 5k. Going to need new gaskets when reinstalling.