Hydrolocked? Yanmar 4JH2-TE

[Icarus]

Originally Posted by Wotname

I still say he is clueless...but kudos for having a go...

[IsaakOker]

Originally Posted by Wotname

Ahh...yes and that is probably because you are better at comprehension that I am .

Re-reading, it does sound like you are right and I am not!

Haha yes, should have specified a bit more.. Rotstional movement, not sideways.

[IsaakOker]

So, my day starts here.
I'm going to start the cleaning up of carbon/rust with the 400 paper, oil, and some scotch Brite.

After all that I'll take the photos, etc.

I obviously was really happy yesterday but don't get me wrong.. I know I'm just getting started and now is when the $ & fine work has to come..but it still is nice to close phase 1 😁

Catch you all later, have a great day!

[dbraymer]

Been there a couple of times.

You want to rotate the engine without breaking any parts.

Can you get a lever on any crankshaft connected component? I am currently speeding around in Michigan in a SeaRay which had a ten year locked up 302.

I rotated it by bolting a 6 foot long piece of angle iron to the primary forward crankshaft pulley, and jumping on it!

Before you get to this stage, it is important that you flood the cylinders with a fluid appropriate for the engine. also you will need to drive the fluid under water in any cylinder, since the hydrocarbons will float on the water. If you are actually dealing with a recent hydrolock, you should be able to flood a diesel with diesel fuel mixed with a rust busting fluid. fill every cylinder up and wait a day. Then try putting a crow bar into the starter mount cavity. Lever the flywheel gear teeth. This should work. If it does not, then you are dealing with a longer time set, or something is really wrong, like a hung valve in the way of piston movement.

If you are still stuck, Before I went for a complete rebuild, I might pull the head. You can have it redone, and then you can do the 6 foot lever thing! You will be able to clean up the piston tops, develop the ring gap a bit, and get the rust busting fluid into/onto the cylinders/walls

[a64pilot]

Originally Posted by Icarus

I still say he is clueless...but kudos for having a go...

We all were to begin with. Although many of us learned basics on cheap Briggs and Stratton engines where mistakes weren’t so costly and worked our way through chain saw engines etc.
I think he needs to find a Mentor someone to teach him, they just watch and consume beer. Surely there is someone around?
I still think the Votec school ought to be looked into.

I wouldn’t use a dingle berry hone, I’d have it honed, the angle and depth etc of the cross hatching is important if you don’t want an oil burner. You have it done as having it done is less than the price of a good hone and when will you use a good hone again?
Many things work, but don’t work well, dingle berry hones are in that list, but the do have their place, they are good for a two stroke to remove the edge on the intake and exhaust ports for example and work fine on brake cylinders.

[IsaakOker]

Good afternoon!

So I've had an initial clean with scotch rite & oil, nothing more aggressive yet.

I'm trying to assess how much work and what has to be replaced in this second stage.
I will highly likely get a mechanic to have a look at it to get another opinion before taking the block to be re-sleved, bored or whatever needs to be done in the end. To me the sleeves look like they have to be replaced but not sure how much they can be honed..

I've uploaded 2 new albums, one called "Cylinders Clean" & the other "Pistons & Stuff"
https://ibb.co/album/iYX2yv
https://ibb.co/album/m5XPBF

Pistons haven't been cleaned yet but apart from 2 rings on one of them they seem good, obviously will check the connecting rod, pins, etc. But they seem fine.

So unless a mechanic says it's not salvageable which I doubt, my plan so far is to:

-Clean the cylinder head
-Clean pistons, remove & replace rings after cleaning grooves.
-measure rods, pins, warping in the block
-Clean injectors in fuel, replace at least 1 as the return pipe is corroded
-replace all hoses, clamps, impellers, bolts, washers, high pressure pipes, starter, mounts
-Clean & check exhaust manifold, intake manifold, raw water pump, alternator.


**what I'm not planing on doing.
-turbo
-fuel pump
-taking crankshaft & camshaft out unless I find something wrong with it after checking them
-oil cooling pump


I bet you have lots to point out from 2 very simple lists. I just made them real quick to see if there is anything major that I should check no matter what & have missed which I bet there is..

The "don't do" list doesn't mean I'm not taking those items serious, just that I want to leave them to the end as I believe the others are easier, faster to repair and because fuel pump, oil cooling pump & turbo can't really be checked until the engine is running right?

Looking forward to hearing from you all!

[Cheechako]

A few things: Not sure your budget, but... if I had gone this far I would want to make things well again within reason.
Injectors: if the tips are rusty pitted etc (likely due to water sitting in there) I would have them cleaned and tested if you can. Moisture deteriorating the tips results in poor injection, rough running etc. It shouldn't be too high $ to have them done.
Cylinders: I can't really tell about the cylinder walls. What do you think? It would be nice to have a mechanic at least hone them, install your rings and pistons so you know it's all good. If he looks at them and thinks you need a bore job that's something else.
Valve guides and valves.: Any idea their condition? A mechanic 's quick look might be worth it.
Pistons/rings: Often hard to get the rings off without breaking. Again, letting a mechanic do the bores, rings, pistons and assembly of that would be good.

[Geoff54]

My 2cents, (again ).

I think those pistons will probably clean up fine. But I'd wait until you are sure about the cylinders.

Honestly, a couple of the cylinders don't look that great and I don't like that vertical scoring in a couple of places. Can you feel the pitting/scoring? I bet you can. If it's not too deep, I'd run a flex hone down it and then see if I could still feel it - but I actually have one and if you bought one, you might still have to have it bore honed. I don't think it needs boring but it's very difficult to tell. A64 and I have disagreed about the flex/ball/dingle berry hones before. I use them and it's the Yanmar recommended method, but they won't remove deep pitting/scoring or correct out of round or taper. I do agree that if they need a bore hone it goes to a competent auto machine shop. Apart from the price if you buy the hone, it's far too easy to remove too much material if you don't know what you are doing. A good thing about going that route is they could hot dip the block which will clean it inside and out. The bad thing about dipping the block is that you'll have to strip it and of course you have to pay for it. Btw, we were remiss in not advising you to tape over the top of the block so that crap doesn't get into the oil and coolant holes. May I suggest that you clean them out and tape them over?

If you can't get away with honing, you'll have to compare price for sleeving + rings, against boring + pistons. I'd bet there's not a huge difference, in which case I'd go with bore and pistons. You get new pistons and there have been cases where sleeves work loose if they aren't done just right.

The crank has some very light scoring, which surprised me as there wasn't noticeable cylinder wear. But it looks very shallow and, from what I can see, the shells look great. Can you feel any ridges - I bet you can't. Unless they are out of round I think you're looking good there.

As for the cam shaft, look down the block and see what the lobes look like. Look for scoring or pitting. Cam lobes are one of the most highly loaded surfaces. If they look ok and the big end journals are round, I wouldn't disturb the crank except that I'd check the end float and side clearances. Then you won't have to re-time it either - although, despite your reluctance, it's not too difficult.

It's probably a good idea to have a diesel fuel injector shop check your injectors. It's not that expensive and they can advise you about the return pipe. There's not a lot of pressure in the return, so you may be able to clean and paint it. An injector shop might be able to replace just the body, saving the cost of a new injector.

Overall, you've got to the point where you need someone local to take a look. It's really difficult to tell from pictures.

The only other thing that immediately comes to mind is to replace the 'o' rings in the heat exchanger. Cheap, easy and you get to look inside the tube stack.

Onward and upward!!

[a64pilot]

Depending on how bad the cylinders are will determine how much money is required. The pistons are a almost certainly OK unless you busted one, and I don’t think you did, cause you would know. Aluminum is very resistant to corrosion, at least compared to steel / iron.
What trips the need for new pistons is the need to bore out the cylinders.
No one, myself included can make a good call via internet whether or not you need to bore or not, that is best left up to an experienced mechanic or machinist who can inspect in person.
However I would not try to reuse the rings, the amount of cylinder wear / metal removed for clean up will determine if you need to fit oversize rings or not, that and the size available of oversize rings of course.
When fitting new rings, you check end gap, that is you use a piston to slide a ring into the cylinder and using a feeler gauge you measure the gap. If too small, you file the end until it’s correct, that is why sometimes with a worn cylinder or one that took a lot of honing to clean up you can sometimes fit over size rings, but file them to the correct gap, the standard size rings will have too much gap. Your in between a standard bore and oversize, it’s back yard mechanics and it’s not optimal, but it works. Not as good as all new of course.

The reason “good” hones are manufactured and sold isn’t to milk unnecessary money from people. It’s because they are necessary to achieve straight parallel bores. Dingle berry hones are OK to break a glaze to get new rings to seat. But if used to try to remove any metal. They won’t leave a straight bore, and that causes problems with rings which means oil burning and low compression.
The cost for a machine shop to hone the cylinders should at least be checked. They are a pros, they have done it hundreds of times and they likely have a machine to do it automatically that is stupid expensive, but they do hundreds of engines per year so it’s affordable that way.

However unless insanely bad, the engine will run, the question is how much oil will it consume and how much down on power will it be.
I mean you can put it back together now, it will run, after you free the rings, they are most certainly stuck now and that loses compression.

I would replace the main and rod bearings myself and the oil pump as a minimum. But it will run if you don’t. But usually bearing are not that expensive, and an oil pump, well that’s the heart of the motor.

A lot of things are normally done just to reset the clock and make it so that the engine will last as long as a new one, not because it’s required to run. You chose the quality of the overhaul.

Overhauls mean different things to different people. To some it’s just bust the glaze, fit new rings and a new coat of paint, those are called Mary Cater overhauls, I guess way back in the day Mary Carter was a popular brand of paint. They last about as long as saw dust in the rear end.

[Geoff54]

I don't think he's silly enough to try to re-use those rings. And I don't believe Yanmar supplies oversize rings except to fit +0.25 pistons. I would hesitate to use those with stock pistons because, if the bore is big enough to warrant them. then piston clearance would be too great and the rings wouldn't locate deeply enough into the grooves. But the truth is in the measuring. The specs are all in the manual.

Just for reference, my cylinders measured exactly to spec after a quick flex hone and the stock rings were right at minimum end gap, straight out of the box. I just rounded the sharp ends a tiny amount and installed them. So I think that he probably has a little room to play with.

One last thing, again getting ahead of ourselves, but I don't want to forget. Remember to drain the muffler and if the engine cranks for bit when you try to restart it, drain it again.

[Compass790]

Originally Posted by IsaakOker

So, my day starts here.
I'm going to start the cleaning up of carbon/rust with the 400 paper, oil, and some scotch Brite.

After all that I'll take the photos, etc.

I obviously was really happy yesterday but don't get me wrong.. I know I'm just getting started and now is when the $ & fine work has to come..but it still is nice to close phase 1 😁

Catch you all later, have a great day!

Hard to tell from photos but your bore wear doesn't look too extreme to me. Plenty of hone marks left. The pitting may be the problem & the depth of the vertical scores. Others have covered that &
But my 2c worth is more about the parts. I'd try to find a tractor equivalent if there is one or check rings/ piston diameter & pin height/dia & see if there is an equivalent. You can sometimes find MUCH cheaper well made parts that come from Japanese joint ventures in Taiwan. Can be very time consuming trying to find out tho. Try Alibaba or Aliexpress

[unbusted67]

I can’t seem to find what it was that actually happened to this engine. was it seized after all?

[BruceS]

Not seized by being cooked but by water/rust/rings gummed .......
Probably could have been freed up with a bit more than 1/2" drive socket but as seen it is best stripped & at least rings freed up in their grooves.
Hard to believe it was only 10 days before that it spun over?

He did well & now it's his decision where he goes from here.

[Wotname]

Originally Posted by unbusted67

I can’t seem to find what it was that actually happened to this engine. was it seized after all?

Also check posts #199 & #201.

[Wotname]

This.

Originally Posted by Geoff54

....... But the truth is in the measuring. The specs are all in the manual....

The manual is very good and gives both service limits and wear limits for almost all the components in the engine. A lot (but not all) of the measuring can be achieved with a set of callipers (vernier or digital), a set of feeler gauges and some plastigage . This will give you enough accuracy to decide if things need to go to the shop or be replaced etc.

I'd even strip and check the injectors - again the manual gives good guidance and if they all appear OK, have them pop tested at a shop - but maybe that is just me