what caused this???

[white03]

Guys,

Stuck #4 on my 1996 225PM...see pics below....what do you think caused this?

[The Big Al]

Yuk!!!! Been thier done that.

Lean condition.
EFI or Carb?

Al

[white03]

It is an EFI

[qmaster023]

just a thought. not much carbon on cyl and lots of water stain on head. could it have been a head gasket. i know they get clean on blow up. just a thought for the rest of you guys.

[RB in NM]

Iz there a groove cut into the side of the Cly wall where a side pinned ring locator come out? Looks like pieces of rings all over the place......
RB

[Lanceonthelake]

I agree. In the second pic, left side of the head, what is that dark line? Is that just the way the pic came out, or is that a head gasket failure:confused: :confused:

[white03]

The dark line is a piece of the head gasket.

I have always used 100% syntheic oil and have never had much carbon build-up...maybe why there is not much carbon on the pistons. All my piston tops look about like that

I'm out of town right now so I can't look at the side of the cylinder wall...will look when I return

[STVmod]

was the cylinder dry when you pulled the head off? if so could of leaned down then broke the ring. If the cyl had oil and was not dry may have just broke ring, then detonation from the dents the ring left in the piston burned the piston up... just my 2 pennies worth

[Lanceonthelake]

The dark line is a piece of the head gasket
I have seen that before where the gasket comes apart. Maybe water came in where that spot is, might also explain why your piston was clean:confused: Were they Merc head gaskets, or ProMarine?

[robert jordan]

thats just the nature of the beast. we have all been there and done that.

[The Big Al]

First, you need to check for cause. It's a easy fix for the piston and bore.

Send the injectors to Brucato to be checked and cleaned.

Check the reed valves.

Al