Failed Freeze plug, Burnt up exhaust, what to fix?

[jdeeewp]

Hello,
I have been around boats a while but haven't run into this yet.

So i am heading out to the bay to check out the air show at the local airport. I notice an odd sound coming from the engine, then notice bilge pump running, then lots of water in the engine compartment, then some smoke, then A LOT of smoke. At this point i am already heading for the dock, and the engine eventually stalls with ~100 Yards to go.

I get it on the trailer and check it out:
failed freeze (core) plug, burnt up rubber hoses on the exhaust risers, and bellows under the out drive is completely gone..

The other rubber hose between the elbow and the exhaust Y-pipe seems to be OK but mot likely going to replace this due to risk of sinking.

My Question is, What else should i inspect for possible damage?

Engine is a 1986 Mercruiser 205, 4bbl, 4.3L, with an Alpha one Outdrive

(yes, hindsight is 20-20, I should have shut it down but at the time i didn't want to risk no start and sink it.)

Enjoy the pics!

 

[Bondo]

Re: Failed Freeze plug, Burnt up exhaust, what to fix?

My Question is, What else should i inspect for possible damage?

Ayuh,... I'd pull the motor, 'n replace All the core plugs, All the rubber parts in the exhaust, 'n put a full kit in the impeller pump...
You'll need to fix all the burnt up wiring, 'n I'd bet the lower shift cable probably melted too...

 

[jdeeewp]

Re: Failed Freeze plug, Burnt up exhaust, what to fix?

Ok, I admit it, I had noticed the freeze plug leaking last year, which is why it failed, I inspected the others and they were not corroded (on the outside) like the one that failed. So i made the executive decision to only replace the one for now. Once boating season is over, i will be pulling the engine if i think its worth it. swap went pretty easy overall. only broke one bolt that attaches the mount to the hull.

Next up was removing the old rubber parts. which is when I noticed the burnt out water shutters. They were there but, full of holes that hold the rubber on the shutter.

Went out and got parts, totaling 350 including shift and U-joint bellows for later, which looked good enough to finish the season.
I really wanted to get the shifter bellows swapped but couldn't get the cable off the shifter plate in the limited time i had. The shifter cable was working fine so didn't have to replace that although i can see that it was resting against the exhaust tube. New "exhaust bellows" x2 that attach to the riser, 1 of 2 new "hoses" that attach the exhaust elbow to the Y tube, and new out drive exhaust bellows. (what a PITA)

I also invented a 6$ tool for installing exhaust bellows, (attached below) which was not worth the futile 3hr attempt without it. The other problem was i didn't let the bellows adhesive dry before attaching it to the bell housing. So it slid of the transom 1/2 way a few times (also not worth the fight but the tool can push it back on as well!). All in all, its on with 75% satisfaction.

Lastly, I am installing a car horn to the bilge pump float switch, with a relay, and a switch to turn it off. That way if i lose the U-joint bellows, shifter bellows or another expansion / core / freeze plug I will know right away (not going to leave the boat floating out of earshot).

Also, what happens when your exhaust bellows falls off? Before you say the boat sinks, wouldn't the risers prevent this?

Thanks for the advise!

Edit: Wiring was OK, conduit did its job!