Exhaust flappers?

[Bski]

My boat experienced a sudden loss of power and can't get passed 3000 rpm. Doesn't buck or run bad, just can't accelerate or get up on a plane. 3k rpm is max now. Runs great when not under load. I noticed water squirting out of the rubber hoses that connect to the exhaust manifolds. <br /><br />This makes me lean towards a stuck flapper valve.<br /><br />Are these easy to get to?<br /><br />97 Glastron with Volvo Penta 5.7 I/O

 

[Bski]

Re: Exhaust flappers?

Read another post about the same problem I'm having.<br /><br />Can someone tell me where the flappers are located in a 5.7 litre Volvo Penta?<br /><br />Thanks.

 

[bolo789]

Re: Exhaust flappers?

the flapper locate in that same exhaust pipe that connect to the risers, very easy to change, i jist change mines on my merc 5.7L i pill the risers bolts, loose these straps that holds the exhaust booth, look the flappers will be right before your eyes. hope i help a little,<br /><br /><br />good luck

 

[Bski]

Re: Exhaust flappers?

Thanks bolo, I just found this a minute ago.<br /><br /> http://volvopentaparts.stemtostern.com/VolvoDiagrams/ShowAssembly.asp?ID=71068 <br /><br />I'm assuming it's #25 in the picture, please correct me if I'm wrong. What I'm not sure about is where that tube goes. I'm not with my boat right now so I'll have to check later.

 

[crazy charlie]

Re: Exhaust flappers?

Thats the one.The tube attaches to the output end of the riser and the tube leads out of the boat through the outdrive .Charlie

 

[Bski]

Re: Exhaust flappers?

Got it, thanks everyone for the replies. I posted another reply on another thread, I found mine to be damaged due to an overheating that occurred a few years back.<br /><br />Got the new flappers and will put in tonight.<br /><br />BTW, the flapper that was semi-stuck fell off the rod when I removed the upper tube and lodged itself down into the Y section. I finally was able to get it out through the rear exhaust exit using a pair of pliers and yanking on it, it was warped so it just barely made it through the hole.

 

[Manipulator]

Re: Exhaust flappers?

My boat is experiencing similar trouble. Ran great the last two times out and now it has to be cranking just to stay on plane. I checked everything on the engine (timing, fuel, ignition etc). It only has 10 hours on a rebuilt carb, new plugs, new wires, new points cap and rotor. I have a GM 5.7 mated to an OMC 800 series. Do the OMC’s also have these exhaust flappers? Could that be my problem? Mine is an 83.

 

[Don S]

Re: Exhaust flappers?

Maybe you guys ought to read this Volvo service bulletin.<br /><br />

<br /><br />

 

[NateCCIE]

Re: Exhaust flappers?

Don, <br />What's merc's current thoughts on flappers? My 93 502 has one broken right now, and was thinking I'd replace them before the motor goes back in.<br /><br />-Nate

 

[Don S]

Re: Exhaust flappers?

Merc still uses them.