my starboard 454cu in 350hp crusader engine

[captddis]

If the fuel system checks out check for back pressure. This is a typical scenario. If risers are clear it could be an exhaust hose with a bubble that expands with heat. Have seen it before.

[uniquename]

i had the same thing happen on a pair of 350 crusaders on an previous boat. after much troubleshooting, the problem turned out to be an exhaust hose that had delaminated. under load the inside ply would collapse and the eingine would bog down. externally, the hose felt and looked fine.

[67HAT34C]

If you think it is possibly a pick up then try shutting off that fuel tank and pull from the other tank.

Exhaust hose bubble sounds interesting. Those of you that have had this problem, where was the bubble. Was it between riser and y or from y to muffler.

[captddis]

They can be anywhere, but are more common near the heat source. The bubbles are common and most go unoticed until hose replacement or a problem.

[Trojan]

Just a though.Before you go crazzzzzy.I have a 32ft..At pull out last fall it ran fine.In the spring it would not plane,1800rpm /2000rpm.Depended on how much help I had onboard.At the dock it would run up in neutral 4000 rpm.both engines.Did all the same things on this thread,3 months worth.Many hours of burnt out brain cells.Every dog that came by with an idea I tried.Finally by chance, I pulled the props.They were one month old in the fall.They checked OK.BUT,the guy at the prop shop pointed out that the keyway on the starboard prop showed that the prop was climbing on the key.There was no vibration just no rpm.or power.Reinstalled the props torqued them down wella 4000rpm. WOT.Just a though that I would have never guessed.I didn't know a prop would do that.Bill