Bad first trip...blew off the rubber riser boot.

[Johnson@H20town]

Good afternoon,

So, on the first trip with my recently purchased 1997 232 I have my first problem. Its the 5.7 GSI Duoprop. The boat didn't have any power, couldn't plane...barely get it over 15kt. This was not at all the boat I test drove. I stop, inspect everything. Gauges are okay. Risers aren't hot. Starts up fine...but no power. At this point, I am in the channel up on the St. Lawrence River, right under the bridge so I continue giving it throttle. All of the sudden....bang....I feel the boat surge like it has 100% power....aaaaaand I now sound like I am in a NASCAR race. I shut down, lift the cover and I see that the port side rubber boot directly off the riser has blown off. I now realize I am in trouble.....so I fire it up just to give me a little boost towards a dock and then jumped in and swam it to a safe place. I am calling for a ride at this point. In waiting, I disconnect the boots and reattached everything as it should be. There was some dark residue in the bilge but nothing else I could see. Once everything was back together I fired it up. Perfecto, runs 100%, drove 100% and my confidence in taking it again with my kids is at 0%. Any clue as to what could cause this. I unloaded, and didn't do anything out of the normal that I haven't done with other boats. The day I test drove it, it was a really cold morning in May. Did I miss something? The owner said he never touched those in his winterizing. He also called up his cobalt dealer/service (with me on the phone) provider and the had not touched anything. Of course, they would like to see the boat.

To me, it was like the backpressure was too much that the exhaust pressure blew off the weakest point. I have attached a pic to show exactly which riser boot (not sure of the actual name).

Like I said, it seemed okay after this eruption(insert Eddie Van Halen ). I went out alone for an hour after and it was fine. Actually amazing. A part of me wants to just bit the bullet and take it to a VP Marina to have it double checked but I know they are swamped right now. Any feedback you have would be appreciated. I will say, I will never not have my toolkit that I assembled for the boat on board....it saved my bacon!

Best,

EJ

[cmattj]

I’m gonna guess you have a y pipe flapper valve issue as some early models had them . ( Stuck so like a potato in the exhaust).
It’s hopeful you didn’t ingest some water as it popped the hose while running as opposed to turning off the engine and in running back in the cylinder.
Get your engine serial number and contact Volvo or your dealer and ask how that series was equipped.
Yes .. she should be professionally checked as you can avoid a big expense .

[akorcovelos]

Looks like that engine is known for failing exhaust flappers. Maybe one broke and lodged in the tube blocking flow, causing the boot to blow off.

https://forums.iboats.com/forum/engine- ... st-flapper

ah, Matt beat me to it.

[Big Block Power]

Man I couldn't imagine those popping off. They are tight. You had a major exhaust blockage. Flappers gone bad like Matt said.

[Johnson@H20town]

Thanks for the feed back and it was like a potato in the exhaust! I believe it was a flapper as well. The metal piece the flapper rotates on is still in and is all that remains. In hind sight I probably shouldn't have drove it around once I put it back together. If I get all of the pieces out(if there is any left) of the "ram horn" am I good to go? I drove it for a while after I reassembled it, back to the nearest boat launch that I could find. It seemed great and I was on the throttle.

I read that these were eliminated from use and are no longer available. Volvo parts website shows it as "obsolete part".

[cmattj]

Volvo parts website shows it as "obsolete part".

Makes sense it’s obsolete.
Kinda like the Old Push button dash on the imperial. Great idea until “ little Johnny” wanted to change the radio for mom and threw it in reverse .
You dodged ( funny ) a bullet of reversion..now get the rest out of there.

[Johnson@H20town]

haha, I drove a Desoto once that had that! Not far off of RAM's having a rotating knob these days!

[akorcovelos]

The flaps were superseded by higher risers to prevent water inversion, I believe it was 3" taller than OE.