Boat: 1996 400 Crusader 454Xli, Velvet drive 20-01-005.
I have a noise coming from my port engine/trans. It seems to be coming from the rear of the motor under the heat exchanger. I thought it was the damper plate (And it still could be) but the engine is running not as smooth as the stbd engine. The noise sounds like two pieces of sheet metal slapping/banging together. Its not a knock. In neutral when I throttle up to 1k the noise almost goes away completely. I have not tested to see what happens when its put into gear.


Everything I read was to get the engine running correctly before dropping the trans and checking the damper plate. I replaced the plugs/cap/rotor yesterday and no improvement. I started to do a compression test but the loaner I had was broken and wouldn’t hold pressure. Next week I will bring my timing light out and check timing. The engine dosnt run horrible. It just has a little more vibration than the stbd. Fuel in the port tank is new.

Here is my to-do list to try and get it running right.

1) Check timing
2) Replace fuel filters
3) Check / replace coil
4) Finish compression test
5) Clean / Replace tb/injectors
6) Call a mechanic and let them try
7) Pull heads and have them rebuilt
8) Replace damper plate anyway while its tore down

Anything else I should add above line #6? As you can see it’s a slippery slope.

Thanks in advance.

Steven