Yanmar 4JH2-TE complete rebuild - next steps?

[LeighWebber]

I just completed a complete rebuild of my Yanmar 4JH2-TE. I have had it in my garage for about 10 months now, working on it in my spare time. My rebuild included:

• Head and block resurfaced
• Cylinders bored, new oversize pistons and rings
• New valves, valve guides, and valve seals
• Valve seats ground and lapped
• Speed sleeve on aft crank journal
• New crank pulley
• New fuel pump
• New starter
• New Elctromaax 250 a alternator, with serpentine adapters, etc.
• New sensors (oil, cooling water, etc.)
• New wiring harness
• All gaskets and seals replaced
• All new hoses
• Complete rebuilt of sea water pump
• Injectors cleaned and tested
• Fuel injection pump cleaned and tested
• Heat excahanger and lub oil cooler flushed
• Rebuilt Velvet drive
• Brand new V-Drive

I had the head and block work done at a machine shop, and the fuel injection work done at a diesel specialty shop. The rest I did myself. I'll attach photos of my baby below.

My question for the group: I want to test run the engine for 8 or 9 hours in my workshop before installing it on the boat. I'll fill it with oil and coolant, per the service manual, and I'll leave the field wire disconnected so that the alternator is disabled. I plan to leave the engine on its stand (the flywheel is free to spin, of course). Some questions:

1. Should I fill the governor with oil, or will it pull its own from the main engine oil?
2. I plan to leave off the mixing elbow and just let the exhaust fly free. Is this a problem? Should I drag my water lift muffler from the boat down to my shop so that the engine feels some back pressure?
3. I neglected to scribe the old position of the FI pump before removing it. I'll set the timing via the service manual (disconnect fuel lines from injectors, bleed air from fuel to FI pump, bring #1 to TDC and note when fuel begins to flow from line 1 and compare with flywheel timing mark) and rotate the FI pump accordingly. Is this going to be good enough, or should I get a timing light plus fuel line pulse sensor and really fine tune it?
4. What should my test run RPM profile look like? An hour at idle, slowly increase to cruise for x hours, increase to 3600 (max) for how long, etc.?
5. After my test runs, I'll let the engine cool thoroughly and then re-torque the head and all the external bolts. Anything else I should do?

BTW - the blue tape tags are reminders for what I need to do before starting the engine (like, fill the oil filter with oil).

[LeighWebber]

Oh -- I should add some confessions and advice to others. When you send your block out, they will remove all the frost expansion plugs to allow them to flush everything. Be sure to replace ALL of them with new before doing anything else with the engine. I overlooked the frost plug that sits behind the fuel injection pump, and didn't notice it until I had reinstalled the gear case flange, gear case cover, F.I. pump, fresh water pump, etc. etc. Had to remove all of that (including the oil pan, which has to come off in order to remove the gear case cover). Then order new gaskets for all those things. A whole lot of work for one lousy frost plug.

Also - the service manual is silent on re-attaching the lifting eyes, which I had removed before sending in the block. It is (barely) possible to bolt on the after lifting eye if you remove the air pipe -- but would be a whole lot easier if you do it the minute the block comes back from the machine shop.

When rebuilding a velvet drive, you will need these: Stanley Proto J250G Proto 9-Inch Lock Ring Horseshoe Washer Pliers https://www.amazon.com/gp/product/B00209ETSS. Don't even think of starting the job without them. And throw a large towel over your head and drape the work piece while you are removing circlips. They are really, really hard to find when the fly across the garage and drop behind your storage shelves. Just sayin...

[LeighWebber]

One more tip. At the beginning, go through the parts manual and list every last bolt, nut, and washer. Then order them from any online bolt place (make sure they are the correct specs, of course). It is so nice to be able to reach for nice fresh bolts rather than clean the crud off the old ones. And no worries about misplacing a bolt in your less-than-perfectly organized garage workshop.

[DougR]

-Prime the governor (and injection pump if oil lubed) with engine oil. Also prime the turbo shaft with engine oil as well.
- put the exhaust elbow on.....much less mess
- time the injection pump as per the manual....timing light not necessary
- warm the engine up and run briefly at various rpms and check for oil and fuel leaks. Not necessary to run for hours, and It doesn’t do any good to run for hours without load anyway.
- retorque the head only if called for in the manual... forget about retorqueing all the other bolts.....
- some alternators will self- energize, even without the field wire hooked up.... be sure the alternator B+ And B- are connected to the battery or starter B+ And ground

[chrisr]

nice work

when you've finished i've got a pair of 4JH2TE's that would benefit. when can i bring them over ?

cheers,

ps : on a more serious note
- how many hours on yr engine when you re-built it ?
- why did you re-build ? ie did it fail in some way ?

thanks

[Compass790]

Speedisleeve on crank journal?????
OOOHHHH that doesn't sound good to me.
Afaik they are meant for oil seals not for bearing surfaces.
Usual method is to build up crank with powder spray & regrind.

But there is a lot I dont know

[LeighWebber]

Compass -- you are absolutely correct: the speedsleeve is NOT on the journal -- it's on the extension of the crankshaft aft of the last journal, that just pokes through the bell housing, and passes through a seal. The thing is, nobody has been able to tell me what that part of the crank is called. "Journal", of course, refers to the portions of the crank that pass through bearings inside bearing caps that hold the crank in place, one at each end of the block and one between each connecting rod. But what is the part called that passes through the bell housing called? The Yanmar service manual and parts manual do not label it at all.

[LeighWebber]

ChrisR -- there were about 2700 hours on it. I pulled the engine because it was leaking oil through the forward seal (the one that the crankshaft pulley goes through), as well as the other seal too. No easy way to change those seals without pulling the engine. Once I had the engine at home, I figured I might as well do a complete rebuild and turn it into a brand new engine again. It's really not that difficult, if you know to order ALL the parts you will need ahead of time.

[Compass790]

Originally Posted by LeighWebber

Compass -- you are absolutely correct: the speedsleeve is NOT on the journal -- it's on the extension of the crankshaft aft of the last journal, that just pokes through the bell housing, and passes through a seal. The thing is, nobody has been able to tell me what that part of the crank is called. "Journal", of course, refers to the portions of the crank that pass through bearings inside bearing caps that hold the crank in place, one at each end of the block and one between each connecting rod. But what is the part called that passes through the bell housing called? The Yanmar service manual and parts manual do not label it at all.

Ok I was just hoping you hadnt been the victim of some dodgy engine reconditioner. Couldnt see a speedisleeve lasting as a journal. But I haven't tried it & won't tho I like experimenting.



It's just called the crankshaft but you would say where the oil seal sits.

Just out of curiosity what was the bore/ring/piston wear like if you measured it?
Yes, if you can pay for the gold plated Yanmar parts I'd agree the full rebuild is the way to go.

[Wotname]

Originally Posted by LeighWebber

Compass -- you are absolutely correct: the speedsleeve is NOT on the journal -- it's on the extension of the crankshaft aft of the last journal, that just pokes through the bell housing, and passes through a seal. The thing is, nobody has been able to tell me what that part of the crank is called. "Journal", of course, refers to the portions of the crank that pass through bearings inside bearing caps that hold the crank in place, one at each end of the block and one between each connecting rod. But what is the part called that passes through the bell housing called? The Yanmar service manual and parts manual do not label it at all.

I don't know what it is called either! However I am quite interested in the details of the speedsleeve and especially how you fitted it as I have a Yanmar crank (2QM20) that has some significant corrosion pitting in exactly that area where the aft oil seal is fitted.

Was the crank 'end' (between the journal and the flywheel taper) turned down to accept the speedseal or did you need a different sized oil seal (i.e. larger ID) or something else?

[chrisr]

Originally Posted by LeighWebber

ChrisR -- there were about 2700 hours on it. I pulled the engine because it was leaking oil through the forward seal (the one that the crankshaft pulley goes through), as well as the other seal too. No easy way to change those seals without pulling the engine. Once I had the engine at home, I figured I might as well do a complete rebuild and turn it into a brand new engine again. It's really not that difficult, if you know to order ALL the parts you will need ahead of time.

thanks.

sounds like you had some bad luck. mine have about 6900hrs on them and still going (fairly) strong...but don't be surprised if they appear on your driveway one morning

cheers,

[LeighWebber]

Originally Posted by Compass790

Ok I was just hoping you hadnt been the victim of some dodgy engine reconditioner. Couldnt see a speedisleeve lasting as a journal. But I haven't tried it & won't tho I like experimenting.



It's just called the crankshaft but you would say where the oil seal sits.

Just out of curiosity what was the bore/ring/piston wear like if you measured it?
Yes, if you can pay for the gold plated Yanmar parts I'd agree the full rebuild is the way to go.

The machine shop reported that the cylinders were out of round enough to need boring, but I don't recall the exact amount. I took their word for it and ordered oversized pistons w/ rings.

[LeighWebber]

Originally Posted by Wotname

I don't know what it is called either! However I am quite interested in the details of the speedsleeve and especially how you fitted it as I have a Yanmar crank (2QM20) that has some significant corrosion pitting in exactly that area where the aft oil seal is fitted.

Was the crank 'end' (between the journal and the flywheel taper) turned down to accept the speedseal or did you need a different sized oil seal (i.e. larger ID) or something else?

They turned the crank down a tad, then installed a speed sleeve that matched the original diameter.

[LeighWebber]

Originally Posted by chrisr

thanks.

sounds like you had some bad luck. mine have about 6900hrs on them and still going (fairly) strong...but don't be surprised if they appear on your driveway one morning

cheers,

Actually, like many jobs on a sailboat, most of the effort is figuring things out for the first time. It would be easy to rebuild another one at this point. I did have a wee bit of experience, though: I rebuilt a 1952 Buick engine back when I was 18. Internal combustion engines haven't changed a whole lot since then!

[briblack]

Any good sources for parts, that you'd recommend?