2007 290 Sundancer running weak

[cads03]

Hey everyone,

I’ve got twin 5.0s. I bought the boat used almost 5 years ago. It does have bottom paint but I trailer everywhere and keep in my shed when not in use. It seems to be running sluggish. It runs fine but seems to be lacking power. I was thinking new caps, plugs and wires to hopefully cure. I can’t seem to get above 4,000/4,100 RPMs WOT. And about 38-40 mph.

I would rather not have the bottom re-done but that may be next if the tune up doesn’t solve my problem. I’m betting it’s never been done.
Thanks in advance for any other advice

 

[scoflaw]

Def. a good starting point. Check compression while the plugs are out. Could also be a CF3 issue.

 

[cads03]

Thank you for the response. I am shocked that I haven’t heard of CF3 problem. I will have to do some forum reading on where to look for the potential issue. Meanwhile, I’m going to do the tuneup. It has likely never been done and the motors are now 13 years old with ~550 hrs.

 

[cads03]

Been a minute since I posted this thread. I did a spark plug change, caps and rotors and the boat now runs amazing. WOT was ~4,700 rpms and 46 mph via gps speed.