servicing Yanmar 4JH3E

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tomtom100

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Hi all
Just looking to service my boat engine as normally get this done professionally but we are heading off to the Caribbean this winter and want to be a little more used to servicing myself -

I was going to do the follwing but please let me know if I have missed anything:

Oil
Gear Box oil
Oil Filter
Fuel Filter (primary and secondary)
Check water level (antifreeze)
Belt

Is there anything that I have missed
Thanks

Nick
 
Whenever embarking on long journeys, it is always a good idea to have a qualified opinion on the state of things.
Even if you tackle the work yourself.
There are so many things that might need attention!
Batteries, Dodgey electrics, Generators.
Dyb, Dyb, Dyb....be prepared
 
tomtom100 said:
Hi all
Just looking to service my boat engine as normally get this done professionally but we are heading off to the Caribbean this winter and want to be a little more used to servicing myself -

I was going to do the follwing but please let me know if I have missed anything:

Oil
Gear Box oil
Oil Filter
Fuel Filter (primary and secondary)
Check water level (antifreeze)
Belt

Is there anything that I have missed
Thanks

Nick
Click to expand...

a lot is going to depend on the hours and items due but, based on my (slightly different 4LHA) you will have the following to consider

oil - oil filter
gear box oil
fuel filters
replace coolant - 50/50 de-ionised water and Texaco Havoline extended life antifreeze
belt
engine anodes
raw water pump impeller
clean raw water strainer
tappets
check engine mounts (of course)

however you should have a clear list in your manual...
 
The smart answer is to do all the items listed in the owners manual for routine servicing.
If do you not have a manual then it would advisable to obtain or download one,.

The workshop manual can be found at http://www.motoren.ath.cx/download.php?filename=yanmar/4JH3.pdf


Also inspect all hoses, cooling system and fuel system.

Take spare filters, belts, impellers.
alternator brushes ?

make sure you have the tools to tackle repairs but don't take tools you'll never need .
 
I have 2x 4JH4E in a catamaran, 2500hrs and 3500hrs

Anodes: Don't think the 3E (or 2E) has an engine anode. Neither has 4E.

Impellers: I carry the spare impellers - but my originals have lasted 3500 hours so far - i open the inspection cover and check . Yanmar engineers confirm that yeah, they're generally bombproof.

Oil: Engine flushing with cheap oil seems to work nicely - empty the oil, change oil filter, refill with cheapy oil, let that all run ten minutes or so, empty all that out - and notice how filthy the flush oil has become in just ten minutes - then refill again. Now you oil will stay bit clean for loads longer which has gotta be better. Any ole 15w/40 will do.

Water coolant: The secondary water (antifreeze) should almost never need refilling. There is Proper Yanmar Antifeeze (don't dilute it) if you want to be all proper.

Belt: the alternator belt should be just tight enough for your fingers to turn it a quarter of a turn. Again, not needed a belt in 3500hours but i carry the spares.

Gear Oil - saildrive SD50: NB - yanmar dealers had a global notification last year that their oil level indicators are wrong so people overfill the box and blow seals etc. Fill only to the very LOWEST mark on the oil filler cap.
Best time to drain gear oil is when hauled ashore - open it top and bottom and leave for an hour or so. SD50 takes about two litres of sae80/90.

Fuel filter change: you should have two filters - paper Racor type (yanmar guys say use 10micron) and the finer (probably black or white painted metal) engine-mounted one. Buy a filter wrench to make replacing the engine mounted oil and fuel filters easy. Careful replacing the square-section rubber o-ring on the Racor chamber, i once got a twist in the thing which meant ever so often the engine was starved of fuel, died but came back, weird.
Once fuel fllters are changed, you need some diesel to refill the Racor chamber with fuel. then release the bleed screw on the engine - 12mm or 13mm hex screw (like a nut) on top above the engine fuel filter - open that and close it a bit to let air out and eventually the engine will start again, and tighten up.

Oil changes and top-ups are easy with a bottled-watr bottle (eg Evian) - use a bread knife to saw the top off and make instant funnel which fits nicely into Yanmar oilfill holes, and pour oil from the big 5litrecontainer into the other bit of sawn-off water bottle, much easier to handle. Now the oil won't go all over the place.

Oil checking can be a bit heart-stopping if just been running the engine even if you left it an hour to cool - you take out the dipstick and argh no oil at all. Clean the dipstick, refit, and it shows the right level. Phew. I do this a few times - the highest level is the right level. You're more more likely to blow seals if this is hard up to maximum than if somewhere in the middle. Somewhere in the middle is the right level.

Raw water strainers. These strain the crud from the seawater and are often the plastic ones and bit tight to open - again the filter wrench useful. The plastic colander-like thing inside just needs washing and brushing clean.

Water inlet pipes: check these very carefully - sometimes they have to follow tortuous routes and eventually might spring a leak. Well, one of mine did. I think it's 25mm pipe, the transparent suff with coiling reinforcy wire all the way along. Take either some spare pipe or at least something to repair a leak.

Hose and nut tightening: the tendency for us amateur engine fixers is to do the service and leave it at that. But the engine nuts and bolts and hoses can loosen a teeny bit and weep oil or water. Look for the leaks, tighten things to eliminate.

Exhaust: the exhaust shouldn't leak at all: look for tiniest leak and buy new 76mm exhaust pipe like jfm did for me in Antibes the moment you see anything bad. This rubbery exhaust pipe will eventually go manky and rust at the reinforcing so you have to replace aftr a few years - it takes hot fumes and water out of the engine so it's just not gonna last forever.

Engine electrical connections: these connect a bit close to some of the water drain outlets so you can get water dripping on to the loom - use cable ties to tidy the wires up and away.

Clean up : get the engine room clean: You can use white spirit on a rag, or spcial industrial wipes and/or even paint the bilge with stuff like Danbline so the placve is clean. This makes it easy to spot stuff and less of an urgh mess to go check things.

Special oil change tips: The oil drain is best done via unbolting the bottom bolt of the oil dipstick tube 19mm socket job. The bolt a a special drilled-through item. It has TWO "Dowty" washers (one either side of the bottom of the oil dipstick tube) - these are washers with little rubber inserts on the inside and you can easly drop or damage them. Good idea to have spares.

Also: re-bolting that 19mm drain bolt can be a mission: loosen the (odd) 15mm hex screw higher up the oil dipstick tube to make getting hold of the thread easier, and once all oil filling/flushing is done tighten up the lot.

Primary water inlet valve: if you have a SD50 or v similar saildrive, the water for the engine actually comes up the saildrive leg from the sea and then on forwards to the engine via flexy pipe. If there was a leak in this pipe you need to turn off the valve. The valve is a little poxy bronze screw valve that looks like a dainty but crude tap on the base (in the engineroom) of the saildrive, and is prone to siezing up. You can use a ring spanner on one end to try lever it to force it a bit, and that mite work - or it mite just nicely bend the top of the tap, but not open it. To sort this make yourself a tool by getting an old socket about the right size to slip over the top of the tap, and then (off the boat) file down two slots in the socket to allow it slip over the useless and now-bent tap handle ends. Ta-rah, your specially-adpated socket (with socket wrench of course) now makes it easy to open and shut the valve. NOTE: to open any possibly-siezed or definitly-siezed valve on outside of the boat you should open it A BIT and then close, and oprn and close again and again etc each time a bit more. Cos the sealing surfaces might have barnacles onnem, and this less likley to score/ruin the insides.

To hell with this DIY option and Things that are a bit much for you: checking the injectors (and doing the tappets while they got the top end parts off) needs A Specialist. In the caribbean i use Simpson Bay Diesel in St Martin on the Dutch side near Island Water World. SBD also have all the Yanmar spares, and cheaper than most places in Europe - esssentially u pay same number of USD as you would sterling.
Another place for spares is in Le Marin in Martinique but loads more spensive - euros innit. However, they do have 2 x Yanmar 4JE motors just sitting there in the window. They also had a spare starter motor just sitting there for when i wreckd mine, 460euros, erk.

Wrecking the starter motor: do this by leaving the key in the "start" position which shouldn't happen, but will if you didn't lubricate the keyhole by squirting say WD40 in there, exactly like I didn't.
 
Engine Service

Good advice from TCM, but I would not put any old oil in my Yanmar 3jh3e.

See this link

http://coxengineering.co.uk/bore.aspx

IIRC should not use any synthethic oils. These are simple engines.

Check all connections near starter and back of alternator, they get hot and can become brittle.
Good luck with it
 
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