Popped through the intake.

[Pmt133]

I've started putting feelers out for replacement... you know, now that the initial shock and pain of my own stupidity in purchasing a used "good" engine is over. Regardless my season is on hold or more likely over for the 19... Spent the last 2 days off enjoying some cold snacks at the marina and running the 33... not at the same time that is.

My plan moving forward originally was to find a truck 4.3 to get me through the year... but spending a grand on a temporary solution doesn't sound fun and there are almost none to be had around me... So plan B is to pull the engine this week and speak to my machinist. Hopefully they can mag and pressure test the block and heads/intake to figure out where the water was getting in. Hopefully with a tank and hone to the block the rotating assembly can be saved and then just do a cam/lifters/valvetrain. I'd do it myself but based on the progress I've made on the engine for the vette (I haven't) it would be best to let them do it. Depending on what it costs I may even sell that 388 to pay for my screwup. Who knows at this point...

 

[Lou C]

If the engine was ever overheated the heads may have suffered damage but the block usually survives in terms cracks. Get the heads checked out & if cracked just install reman heads. That’s what I did on mine back in 2017.

 

[Pmt133]

I'm leaving no stone unturned.

 

[04fxdwgi25]

Was it a marine rebuild or an automotive / truck rebuild? Being a raw water cooled engine (I don't see a heat exchanger), the gaskets, freeze plugs, water pumps are different (and cams are marine, not automotive grinds).

 

[Pmt133]

Was it a marine rebuild or an automotive / truck rebuild? Being a raw water cooled engine (I don't see a heat exchanger), the gaskets, freeze plugs, water pumps are different (and cams are marine, not automotive grinds).

I have no clue. Freeze plugs were brass, all the gaskets I saw were merc part numbers but I didn't go deeper than that on it. Like I said, bought it used from a mechanic but... they'll say just about anything if it means making a buck and is one of several reasons I work on my own stuff. It came out of a boat is more or less the info I was given but the rebuild tag was from a marine rebuilder. As far as cams, I didn't pull it that far apart. I honestly don't plan to... I'm going to yank it and bring it to my local machine shop because I really just don't want to deal with it right now. They do tons of marine engines and they've built some exotic things for me in the past so I trust their work.

 

[Pmt133]

Engine is pulled, at the machine shop and they have started working on it this morning. Maybe I'll get to salvage the tail end of the season. Pulling the exhaust manifolds off, there was water in both ports. I broke down the manifold and elbow and it would seem like a slight weep at the joint was occurring, confirmed by filling them with water prior. There is also a hole in the floor of another manifolds exhaust port. Long story short, despite being brand new, those will be going in the garbage.

 

[Pmt133]

So... engine should be done at the machinist next week. Basically, the amount of bore tapper it had he said there was no possible way it had as little use on it as the guy claimed, or the rebuild was crap. Crank pitted, bore looked like sand paper etc. Whatever happened he guesses from prior experience had been like that for at least a year and sat most of it to cause that damage. Everything checked out fine sonically, pressure, and mag wise. Most of the damage stemmed from the cylinders so his best guess is the manifolds/risers. Based on my findings, I concur. He couldn't believe and me either, that it didn't launch apart. It was rough but looked pristine from the pan only. I can't believe it didn't make a damn sound or that there was hardly any metal in the pan. The ring in the bad bore was filed down significantly and there was hard scuffing on all 6.

At least I know exactly what I have now.

 

[Pmt133]

Engine is ready for pickup. They honored the original quote too.

 

[Pmt133]

She's alive for those curious and following along at home... Hopefully doing the sea trial tomorrow.

 

[Fiberform71]

Hopefully it works well now. Good luck

 

[Pmt133]

Hopefully it works well now. Good luck

Thank you.

I didn't run it terribly long on the trailer... basically brought it up to 1500 of so to warm up then set timing. It was pretty close for me stabbing it in at 1am. Think base timing ended up being about zero degrees. Before adjusting the timing I was getting a little burbling but with how thunderbolt V works and the fact it pulls timing at idle it seems, I expected that. Cleared up once set. No more fuel smell idling on the trailer unlike before... Only odd thing was the manifolds and elbows... starboard still even with all new parts was warmer than port. But port was ice cold and starboard felt like you put your hand on someone's forehead. So not bad. I still have to put the drive on but beyond that... pretty much ready.

I'm planning on sending some oil samples to black stone. Just to make sure there is no water intrusion and that everything seems kosher. Had a very steady 50psi of oil pressure that didn't really seem to move any which way on the trailer.

 

[Pmt133]

Still seeing a little condensation through the breathers but I'm not getting anything in the oil. Put about 6 hours on it yesterday. Running fantastic. I kind of made the assumption that 3/4 throttle is ~3/4 RPM so I was just doing sweeps and varying speed from idle up to around 3800 RPM and back down. Overall very happy.

 

[Fiberform71]

Nice to hear that the first trip went well

 

[Pmt133]

Got about 12 hours on it between yesterday and today... I had a noise. Not sure what it was and couldn't duplicate it. I'm putting the celebration on hold...

 

[Scott Danforth]

Describe the noise

 

[Pmt133]

Describe the noise

All three of us heard it, dad and my buddy would describe it as they thought I clipped something in the water but it originated from inside the boat.... I almost thought it was detonation. Picture tapping a wrench on a piece of hard plastic or something once or twice. I wasn't running it terribly hard but I backed off after that as I was about 40 miles from the ramp. We also searched around real quick to make sure it wasn't a water impact but for it to be that loud I should have felt it too. I'm pretty vigilant in that regard so i really dont think it was that.

I ran it really hard later in the river to try and duplicate and got nothing. Per the break in procedure I was allowed short bursts to WOT as I was beyond 10 hours so I did sweeps up to wide open holding for a minute and then backing down to 3000 rpm and repeating.

Tomorrow I plan to change the oil, take a sample and send it out to Blackstone, pull and inspect/replace the plugs (with all the assembly lube used I feel it would be beneficial) and then double check everything else... manifold torque, elbow, etc.

 

[Scott Danforth]

check your fuel water filter for moisture.

a batch of water will hit a cylinder and not fire. that cylinder will make a shudder.

 

[Pmt133]

check your fuel water filter for moisture.

a batch of water will hit a cylinder and not fire. that cylinder will make a shudder.

I'll pull it and check. But I will go out on a limb and say that's probably not going to be the issue. But it's cheap enough and won't hurt and I'll be in there anyway. I'll report back.

 

[Pmt133]

I haven't gotten to pulling the water Separator as I'm out of town but I did pull the plugs before I left. Oil looked clean but it was hard to tell. Tray got wet in the bilge as I was waiting for the adapter for my quick drain and dipstick to arrive so it was just a plug. I plan to run it a little more when I get back and pull the Separator first.

Plugs:
Left to right: 5, 3, 1

Left to right: 2, 4, 6

 

[Lou C]

Those look good, maybe could go a tad richer, but no sign of water or oil