Tough day out

Pat310

My son invited some coworkers out for a ride with us. Awesome. Get to the boat start the engines port engine stalls and throws an IAC code. Restart every thing good. About 25 minutes out starboard engine overheats. Shut down immediately port into neutral. Port engine stalls, wont stay running , IAC code again. Open hatch, water all over starboard engine. Into spare parts box and had an old IAC that was working when I changed it. Swap it in, port engine running, limp home on one. Problem is when engine cooled and tried to restart to have power steering to dock, cranks fine but wont start. Any suggestions on where to start looking for problems with starting after an overheat episode? 2003 5.0MPI 

Pat310

By the way leak in cooling causing overheat was rotted out plug in manifold that looks like someone replaced the brass one with a steel on. Uhggg

PickleRick

Have you checked for spark?   I hope you were able to cut the engine before it got too hot. 

Pat310

@PickleRick its Hard to say. Shutdown 5 seconds after buzzer sounded. Definitely not hydro locked so don’t think I warped head. Could fuel system vapor lock from heat?

PickleRick

It can happen but it's rare on EFI high pressure systems.  

I don't know if you're in salt or not but my thought is something electrical didn't like getting doused in water, causing a failure.   Loss of spark.   Hooking a timing light up to your motor and turning the key is probably the easiest diagnostic there is.  If it flashes you have spark, if it doesn't you don't.    Having two motors means you can start swapping parts to find the culprit. 

Pat310

Thanks @PickleRick. Good advice (as always from you)  on a place to start 

PickleRick

You're very welcome and good luck.  Hopefully it's something simple.  

Pat310

More bad news. The salt water being pumped out like power washer hose was directly under the plastic flame arrestor cover and directly into the throttle body and the engine is now toast. For anyone with raw water cooled off this vintage engine GM sends engines to Merc with the steel automotive plug but list the replacement as brass. Very expensive find for me. Mechanic says not that uncommon. He’s seen it many times before

TonyG13

Ugh! Any chance insurance can/will cover the repair?

PickleRick

That's crappy dude.   Sorry to hear. Not the simple fix anyone wants to see. 

. 

Dream_Inn

Sorry to hear that.  All because someone couldn't put in the correct plug!

captkevin

sorry to hear

PickleRick

So since it's not our cash and we want to live vicariously through someone else's upgrades what's the game plan?  Replacement 5.0?  Perhaps a pair of 5.7 or 383....or even 6.2 upgrades?   

captkevin

8.1

PickleRick

Sometimes you need 1000 horse power