Hydrolocked? Yanmar 4JH2-TE

[Cheechako]

Originally Posted by IsaakOker

OK, bad news..

Had you all guessing for ages but I just noticed a line across 1/3rd of the flywheel.
It's a rust mark showing that the engine Had been submerged before I bought the boat.

I didn't notice it because after I had it turning 2-3 weeks ago the mark is on the starboard side and not at the bottom of the engine but it's obvious now so let's see how the inside looks after I take the sump off..

You know, based on a couple comments I almost mentioned and asked if it might have been. Was going to ask if you see any waterlines on the furniture cabinets...

[IsaakOker]

Originally Posted by Cheechako

You know, based on a couple comments I almost mentioned and asked if it might have been. Was going to ask if you see any waterlines on the furniture cabinets...

Surprisingly no.. There was humidity damage so I planned on getting the cabinets done anyways but even now looking I can't find any marks, not even on the black hoses that are for the water intakes, and water outlets from the cockpit.. Also the gearbox doesn't show any lines but the coupler is very rusted so wa sobviously submerged..

[Cheechako]

Inside cabinets under sink etc? Did you have a survey? I'm not sure you mentioned what model boat this is...?

[IsaakOker]

Originally Posted by Cheechako

Inside cabinets under sink etc? Did you have a survey? I'm not sure you mentioned what model boat this is...?

No to all of them!

I work on repairing fiberglass, wood, electric, rigging.. That's my job so I bought the boat as is, cheap knowing it has a loot of work but the engine is a bummer because as it turned back then I expected it to be salvageable. Mbut now I want to see what it looks like inside.. Probably horrible..

BTW, a hunter 42.

[jimbunyard]

Originally Posted by IsaakOker

No to all of them!

I work on repairing fiberglass, wood, electric, rigging.. That's my job so I bought the boat as is, cheap knowing it has a loot of work but the engine is a bummer because as it turned back then I expected it to be salvageable. Mbut now I want to see what it looks like inside.. Probably horrible..

BTW, a hunter 42.

Don't despair quite yet. That it turned so easily before means that it will turn easily again. Liners are replaceable, cranks are turnable, etc. Even it the line is across the top third of the flywheel that depth shouldn't allow water into the engine.

Setting the engine on the flywheel housing to remove the oil pan is standard operating procedure...

[Captndave1]

Strongly recommend you purchase a service manual and study it in detail before continuing or hire a diesel mechanic.

[Geoff54]

I don't know this boat but the engine sits quite low down in most sailboats. Is it possible that the bilges filled up to the point where the water reached part way up the engine without flooding out onto the cabin sole and therefore the bottoms of the cabinets? In which case it is quite possible that water did not enter the engine at that time.

I would guess that it became flooded from excessive cranking with the raw water through hull open, as you originally suspected. It'll be interesting to see what you find inside.

Hang in there.

[Geoff54]

Originally Posted by Captndave1

Strongly recommend you purchase a service manual and study it in detail before continuing or hire a diesel mechanic.

Did you actually read the thread? He has a manual and has been doing quite well so far. He's learning fast. I suspect that hiring a mechanic would blow his budget and he probably wouldn't learn much except how expensive pro. help can be. Good luck to him.

[Geoff54]

Originally Posted by IsaakOker

Also the gearbox doesn't show any lines but the coupler is very rusted so wa sobviously submerged..

Those couplings are well known for their ability turn into a rusted mess. The amount of violence needed to separate the coupling from the shaft on my boat was amazing, just because, when I got the boat, the stuffing box needed adjusting and it had been wet in that area.

[Wotname]

Originally Posted by Geoff54

Did you actually read the thread? He has a manual and has been doing quite well so far. He's learning fast. I suspect that hiring a mechanic would blow his budget and he probably wouldn't learn much except how expensive pro. help can be. Good luck to him.

Exactly!
Clearly the OP is a practical person with a bunch of other boat related skills, a rational thought process and presumably good hand skills. He is now adding diesel engine rebuilding to his repertoire.

There is variety CF members with engine related backgrounds willing to offer advice when asked so he has access to a wide skill set if needed.

This is not a hi-tech engine and so why pay someone to do work you can do (or learn) yourself. Unless he is time short of course!

Besides we wold never know the journey and answer to this mystery if it was hand-balled to a pro!

[a64pilot]

Being a turbo it’s not exactly a low tech engine either.
I’d recommend removing the engine from the boat and doing the work inside a building somewhere, and honestly you can buy an engine stand pretty cheaply, it will make reassembly a lot easier.

This is a big deal, it’s quite a bit of technical work, and many things will have to be hired out and need to be done, like the fuel injection pump being reworked and the block being bored, cause I don’t think it has wet liners. The head too, this is a Diesel so don’t try lapping the valves yourself, and do not have the head shaved if there is any way out of it.
The crank needs magnafluxing and if your lucky just polishing, but it needs to be mic’d or use plasti gauge at least.
Then you have the turbo and intercoolers etc.

You should strip the block, and have it boiled, this will remove the cam bearings, you pull the freeze plugs too.

Ideal is to find a friend that has overhauled Diesels before or sometimes a Tech School will do the rebuild if you pay for the expenses, their labor is free so the students learn

[IsaakOker]

Good evening/afternoon everyone!

So I managed to get the oil out without any noticeable water in it. I then went ahead and laid the engine on to the flywheel housing & removed the oil sump/pan which was very well sealed... It's a shame that I will have to put all the seals which were all perfect, back on new.. Haha

At a first glance, there is nothing broken, rusted, etc. But I'll have a better look tomorrow morning. It has been another long day as with a chain hoist, screwdrivers, socket wrenches and spanners some steps are rather hard due to rusted bolts or turning the engine alone inside a boat.. 😂
I think I'm going to get an impact socket wrench for future engine repairs haha.

As jimbunyard said, no water inside except of maybe 50ml which probably is from condensation or who knows what.

The only thing that does seem stuck are the crowns as I can see traces of rust on the bore walls seen from below so maybe I just wasn't trying hard enough but I do believe that I would over tighten the crackshaft pulley if I jumped further on the 5ft tube..

I'll take some pictures tomorrow and will as for opinions, I suppose the next step is to release the two bolts at the rods to hit the crowns with a block of wood or should I hit them upwards so that I have a clear way? (as I'll anyways need access to the bores and as a minimum the rings have to be replaced).

The only sign of rust are a few droplets of water the size of a screw head on the rod to crankshaft joint(can be washed away with a finger touch).

The interior block walls are also orange but no flaky rust, just the surface color change.

I'll be glad to hear your thoughts again now that I have acces to this engine 👍

[IsaakOker]

Originally Posted by Geoff54

Those couplings are well known for their ability turn into a rusted mess. The amount of violence needed to separate the coupling from the shaft on my boat was amazing, just because, when I got the boat, the stuffing box needed adjusting and it had been wet in that area.

Surprisingly this one came of easily.. I think I just Was too tired yesterday to even try hahah

I basically got a gap and went around with a wooden taper I made.. Came of smoothly

[Wotname]

Originally Posted by IsaakOker

Good evening/afternoon everyone!

.........
The interior block walls are also orange but no flaky rust, just the surface color change.

I'll be glad to hear your thoughts again now that I have acces to this engine ��

Good progress!

FWIW, the few Yanmar engines that I've seen inside have all been red/orange - I assumed it is paint or some cast iron sealing stuff and consider it is good sign.

[IsaakOker]

Originally Posted by Geoff54

I don't know this boat but the engine sits quite low down in most sailboats. Is it possible that the bilges filled up to the point where the water reached part way up the engine without flooding out onto the cabin sole and therefore the bottoms of the cabinets? In which case it is quite possible that water did not enter the engine at that time.

I would guess that it became flooded from excessive cranking with the raw water through hull open, as you originally suspected. It'll be interesting to see what you find inside.

Hang in there.

Yes, this engine is god damn low.. Like very low.. Like 2" in the bilge.. 🤔

Production boats I suppose.. Hahah the rest of the wiring, cabinetry joinery work, reinforcements, etc ins incredible but that's what I'm doing.. Making her better than before haha