99 Speedster Sk Starboard Engine 5800rpm max

[Toby7777]

I’m looking for a little troubleshooting help. I have a 99 speedster sk and the starboard engine feels like it hits a rev limiter at exactly 5800rpm. The other engine is smooth to 7500+. I’ve switch carbs between the motors and switched the impeller assemblies. Both motors have good compression between 145/147, 147/148. I’ve checked butterflies open fully, I’ve swapped fuel pumps. All fuel lines are new. So far no matter what I swap from side to side the problem stays starboard. Any ideas?? Thanks.

 

[Raven888]

Are you sure it is only revving to 5800 rpm? The tach could be wrong.

 

[Toby7777]

Good point, I’ll try swapping tach harnesses to confirm, but it doesn’t sound or feel like it’s revving to the 7000,s. Also it doesn’t matter if I’m at 3/4 or WOT, it still hits a wall at 5800rpm.

 

[Toby7777]

The tach was the problem. Thanks Raven for the heads up. I swapped tachs and the port engine showed 5800rpm max. Interesting that the tach can go out of calibration. Is there a difference between 99 Speedster tachs with the 787's and the Speedster SK with the 717's?? I noticed this tach has a different part number sticker on the back.