Ahhh! Stumped! Water in oil/cyls!

[Phatty5BMW]

I get what you're saying but the issue wasnt always boiled down to tele logs or center rise, but maybe reversion from the y pipe (which could still be an issue) because sometimes I'd get some water, sometimes not with the old engine and new. I was trying to eliminate that instance as well by running on muffs. That is why I was stumped because of the frequency of the issue.

 

[Phatty5BMW]

3 people besides myself said that the way this headgasket is blown and the severity of the damage to 1 cylinder and not the other is not from water. 1 person being a certified gm tech and the other owns a high end performance shop owner. The #5 piston right next to it is totally fine which has just as much headgasket failure as #3.
I do get what you're saying on how damage may occur, I'm not a newb on boats or engines, hence the frustration.
on the other hand, the old engine was torn apart and no headgasket failure, no intake failure no failure at all so my suspicions as to the root cause was still in the air and frustrating!
I wouldn't have put old logs on it (which i have done the acetone test to and didnt leak) if I knew that was the issue! It's hard to tell everything through typing and the details ice forgot to list. This is the 3rd year of dealing with it lol.

 

[Phatty5BMW]

 

[Phatty5BMW]

 

[Lou C]

Looks like it was severely overheated and/or run extremely lean on those cyls....

 

[Lou C]

Looks like it was severely overheated and/or run extremely lean on those cyls....what timing setting was used, how about total timing advance.

 

[thumpar]

That doesn't look like just a bad head gasket.

 

[Bondo]

Ayuh,.... Looks like detonation to an extreme,....

 

[TurtleTamer]

That's pretty hardcore. Never have seen a head gasket go that bad. At least now that you have all new exhaust, you can put a new long block in it and have no worries.

 

[Rick Stephens]

Heartbreaking to put in a new motor and have it fail so spectacularly. I feel for you.

 

[Rick Stephens]

That's pretty hardcore. Never have seen a head gasket go that bad. At least now that you have all new exhaust, you can put a new long block in it and have no worries.

I would still be worried about why it happened. I would think that if it were detonation because of timing and leanness, that the damage would be more extensive in other holes, not just limited to 3 and 5. What do the valves look like? Were they possibly damaged by a hydrolock? I don't get this yet. The pattern of failure doesn't quite fit what I expected.

 

[Phatty5BMW]

Valves everything look fine... cyl 1 doesnt even look like its been fired, funny part is besides all the damage thats apparent and besides the intrusion of water, the engine ran pretty damn good. If it wasnt taking on water I would have never expected any internal damage an I'm not a newb. Engine seriously ran excellent that's why I never even would have believed head gasket let alone this type of damage! Last resort was pull the head and low and behold lol.
the engine was never really hydrolocked, it took on water but I've done seriously 6 oil changes in the last 2 weeks to get the water out, main and rod bearings everything is good. I'm dumbfounded how so much damage is here in such a short period of time.

 

[TurtleTamer]

Yeah, it's an SBC. One of the things I love about 'em. They will run pretty much no matter what.

FWIW this time I'd spring for an actual Vortec engine. Full roller block and all. I've never been a fan of using the older blocks with Vortec heads but that's just a preference of mine, and I'd agree with your sentiment of avoiding the same place you got that one, if nothing else just for peace of mind. I don't know if your temp gauge is off and you really overheated it bad, or if there was an intake leak at #3 that caused it to go lean, or the head wasn't torqued correctly, but I would agree that the damage is not solely from water reversion from the manifold. That appears to be the case for #7 based on the steam marks, but for the rest, yeah, something else was up.

 

[Bondo]

I'm dumbfounded how so much damage is here in such a short period of time.

Ayuh,...... Detonation,......

A lean fuel condition,.....
Advanced timin',....
To big a prop,.....
High motor heat are but a few causes,....

Combine a couple, 'n a motor will self-destruct in a few minutes, or less,....

 

[Phatty5BMW]

Prop hasn't changed from the ol 228 it had it it. Motor never got hot, ran a mech gauge and the electric, both on point. As for timing, I was getting to do that and my old balancer walked the shaft rubbing on the timing cover. Boat hasn't been in the water since and balancer was replaced, and timing was dead on the mark.
I have a edelbrock 1409, edelbrock marine intake. With the ol 228 it ran max 42mph. This setup was running 50. For that hour. Teardown of the old engine nothing I saw was a culprit

 

[Rick Stephens]

With the same prop, the old engine ran 42 MPH and the new one ran 50 MPH? Only way it can do that is if it was over-revving on the new motor or way way under-revving on the old motor. That is a big increase in speed. Did you check your tachometer accuracy? What was max RPM at WOT?

I have a 1409 in my boat.. One of the nicest to calibrate carburetors made. Did you do any calibration checks? I ask because if it came out of the box and went on the engine, you are not guaranteed anything on calibration. The 1409 can be run on anything from the 4.3L V6 I have up to a 6.2L V8. Very easy to have a lean spot and not know, particularly when running near WOT with the secondaries fueling the motor. In my opinion, it needs to be run at a given throttle setting for 5 minutes and do a shutdown and pull a couple plugs to see how the mixture is at that setting. I like 1/4 throttle to start, then wide open primaries with no secondary opening at all. Then WOT with full secondary opening. That would be my minimum test sequence for the 1409. It is extremely easy to have a low float height cause leanness when at WOT. You cannot expect out of the box that the factory guys cared enough to set something as simple as float height correctly.