Logo
FULL SITE MENU

200 HPDI Went Boom But How

S

square_grouper

New member
"Just left the mech shop and t

"Just left the mech shop and the new powerhead is in place, they are going to put a couple hours on it today and then it is all mine. Here are the findings:
-1/4" chunk missing from the edge of the #2 piston exposing the rings
-Found approx 6 oz of dirty water/fuel mixture in the VST (Vapor separation tank)
-A couple drops of water in racor bowls (Nothing out of the ordinary)
-Gunk in the screen inside the VST.

These findings prompted the tech to check the VST on the other motor for any water and he found none.

Boat is a 2550 Bluewater (Single fuel tank)

Here's a little info on previous maintenance:
-Motor had 383 hrs when it went boom.
-Racor's replaced at 300 hrs.
-Fuel filter on motor replaced at 300 hrs.
-VST filter replaced at 300hrs.

So I am totally stumped here. HOW does 6oz of water get past A. Racor, B. Fuel filter on motor, C. VST filter ???????? Computer never showed any water in fuel warning either. So basically the possible cause is that the water leaned out an injector, causing detonation.

Any opinions?"
 
"Jay, did this model have the

"Jay, did this model have the water cooled intake crankcase? which leaked and the water, being heavier than the gas was scavenged back through the recovery system? So water came from the cooling system.

Wild guess, still trying to get a complete understanding of how these things work..."
 
"well first sounds like you ar

"well first sounds like you are not doing reg maintenance on it
you need to drain racors everyday of use
check fuel filters every 6 months or 50hrs
change filters every year or 100hrs
vst needs to be cleaned every year

what oil are you using?

ask rodbolt on iboats he is the only master certified tech i trust in USA
but do not PM him, he never checks"
 
"Perhaps I should have stated,

"Perhaps I should have stated, "Last maintenance" instead of "previous maintenance". Motors are properly maintained at 50 and 100 hr intervals. I simply listed when the items in question were most recently replaced/serviced.

Using Yamalube and ring free.

All is back together now, 2 hrs on the new powerhead. All new filters as well. Plan at this point is to closely monitor the fuel for the next few runs, checking the racors after each run, and draining the VST to check for water in the fuel. As the tech said, if he knew how the water got into the VST, he wouldn't be working. We don't even know for sure this was the cause, but it is the only thing we had to go on."
 
Back
Top