Water caps? on an Inmar engine 2001 Sportster

[GentilM]

Hi,

I have a 2001 Malibu Sportster with a flush kit. I use the hose fitting on the back of the boat every year when taking it out of storage to run water through the engine while I get it started for the first time (whil sitting in my driveway). Well... this year I forgot to put the battery back in BEFORE I tried to start the engine (duh!) and by the time I realized it the water pressure had built up inside the engine & two metal caps (on on each side of the engine under the motor mounts) blew out & the water came gushing out the sides of the engine. The engine still ran fine (after I put the battery in) even with the caps out, but I don't think the engine will cool properly this way. I have attempted to replace the caps, but can only get them in most of the way. My question is: Should I be worried about this & take the boat to a mechanic (who can lift the engine & replace the caps properly) or am I ok with them as is?

Thanks.

[vette-ski]

I assume what blew out was the expansion plugs, more commonly called freeze plugs but that's not really why they are there. They would be brass about 1-1.5" in diameter? I really don't know how those could have blown out just from water pressure. Your system is open and water should have eventually ran out your exhaust so pressure wouldn't build. I'm confused on this one. And I would have expected a gasket to let go before blowing a plug out. I'd probably look around a little harder for freeze damage (cracked block).

As for the repair, they aren't hard to install but can be tricky. Especially down in the hull of a boat. One tap too many and it's now on the inside of your block where you don't want it. I'd probably have a pro look at it if I were you.