Yanmar Starter Is Intermittent

[Capt.Don]

I have a similar (same) problem with our Yanmar 3GM. My problem is intermittent so I can't measure voltages. Every once in a while, when pressing the start button, the engine won't start. As Vasco said, the switch has a "sweet spot". if we press again (or slightly different position or pressure) the engine starts right up.

I've looked at the push-button switch (round, rubber enclosure, size of quarter - it doesn't seem to come apart for cleaning. I like the suggestions of checking the fuse holder, running larger wire or adding a solenoid to the circuit. Also may look for the connectors on the solenoid. This gives me some ideas on tracking this down. Thanks!

BTW, this could be the reason the previous owner had the house and start batteries wired in parallel with a solenoid activated by the start switch. I disconnected this not wanting the complexity and potential for problems.

[Dockhead]

I wish I had seen this thread last year, when I had this problem on my 4JH3HTE! It happened to me at sea, in a storm, when I needed to take down the sails and start the engine to motor through a nasty channel. It was ghastly. Sailed through the nasty channel, hove to, and spent the whole day trying to get the engine started. Eventually called for a tow. One of my worst days at sea. NOW I know what to do!

This thread should be a sticky! And shame on Yanmar for this dangerous defect.

[Therapy]

Originally Posted by kiltym

The relay part# I use:
Tyco
12V
V23234-A0001-X032

There are 5 pins on the relay:

87 - Jumper to starter male spade terminal
86 - Wire from Yanmar panel (used to go directly to starter)
30 - Positive jumper from large positive cable attached to starter.
85 - To Ground
87a - Not used


So, without this relay, you have 1 large nut on your starter, with a rather thick positive cable on it (this should come from your start battery). And, you should have 1 smaller cable, with a spade female disconnect on it that is connected to a spade post on the starter (this will come from the Yanmar engine panel at your helm station).

You need to remove this wire from the spade on the starter, connect it to position 86 on the relay. Then you make two short runs of cable, one going back to that spade male terminal on the starter from position 87, and another one from the big nut/positive cable on the starter to position 30 on the relay. Then a short ground wire to your engine ground from position 85 on the relay.

I don't have one of those but if I did I would owe you a lot.

[Vasco]

Originally Posted by Dockhead

I wish I had seen this thread last year, when I had this problem on my 4JH3HTE! It happened to me at sea, in a storm, when I needed to take down the sails and start the engine to motor through a nasty channel. It was ghastly. Sailed through the nasty channel, hove to, and spent the whole day trying to get the engine started. Eventually called for a tow. One of my worst days at sea. NOW I know what to do!

This thread should be a sticky! And shame on Yanmar for this dangerous defect.

My 4JH3E came with what they call a "slave solenoid" which is a relay before the starter. I think Yanmar did this to remedy the light wiring problem. Funny thing was that after a couple of years the slave solenoid used to stick and I had to hit it with a hammer. I finally replaced it and have had no further problems.

[Bucaniere]

Very interesting thread!
Does anyone know exactly the type of relays mounted on Yanmar 4JH3-HTE?
I have two of them, one to help starting solenoid and one (I think) to stop the engine. I think I can find them in car spare parts shop, but I don't know how many Amps, type,ecc...

Thanks, Lorenzo

[cal40john]

Originally Posted by Capt.Don

BTW, this could be the reason the previous owner had the house and start batteries wired in parallel with a solenoid activated by the start switch. I disconnected this not wanting the complexity and potential for problems.

This is straight out of Calder's book on making a cheap ACR. This circuit cross connects the batteries whenever the engine switch is on to charge both batteries. It also disconnects the 2 batteries as soon as the engine is off.

If you don't want to use both batteries to start the engine he says to use the engine oil pressure switch to power the relay. With my engine on a cold day this would cross connect the batteries while I was still trying to start it, as the oil pressure switch closes after a few seconds of cranking.

John

[bchbum1972]

Great, Started having starter issues, I put the relay in as posted above. Worked like a charm!!! Thank you!

James
s/v Jaffo 331 Beneteau

[marina.alex]

Hi everyone ... very good thread.
We also have a 4JH3-HTE on our Beneteau 50 with 4200 hours on it. We've put 1500 hours on the engine ourselves and it has started like a champ the whole time ... until today. I turned the key, nothing happened, tried a few more times and it started -- I thought it was weird but ... it worked and restarted several times during the day as we alternated from power to sail, to power to sail. After sailing the last 10 miles plus all the way through the Preveza channel (Greece) we were about to go stern-to and the motor wouldn't start. Key would turn, a small click and then nothing. Shortened sail and dropped the anchor under sail ... glad we practiced that maneuver before.

My access is OK but getting at the starter solenoid was difficult and hard to see not to mention unbelievably hot. I could see and hear the small green relay (G Cartier) that has 4 blade positions on the back 1-2 and 3-5.

Anyway, I removed the starter and tested it and the solenoid and they're ok.
Then I reinstalled everything, cleaning up the contacts on the relay and the solenoid -- we turned the key and it worked.

Then we turned off the engine, tried to restart -- nothing.
I tested the wire to the solenoid with my multi-meter when the key was switched and didn't get much if any volts -- millivolts are all that came through.

I removed the wire to the solenoid that controls the it and then rigged up a remote switch -- started no problem.

So ... here's what I am thinking ... it's the little relay that needs to be replaced. I believe after research that they do wear out, that they are also like small solid-state solenoids, and that this should fix the problem. I also shot some WD40 on the back of my switch in case it got wet from when we were swimming -- but you'd think that would have happened sometime over the past several years ...

I wasn't sure how I can test the relay to see if it is working properly. I have zero tolerance for intermittent problems and want to get it fixed permanently and right away ... Any thoughts or advice?

Thanks ....

[Bucaniere]

Hi Alex, I've solved exactly the same symptoms replacing the starter-helping relay. Unfortunately I don't know too much of electricity but I think that on our engine there is (or maybe you have to install it) a relay that help the starter, bringing to it the necessary current.

It's a 2 Euros friend like this:




Let us know.

Sorry for my bad English

[seadrift]

My Yanmar 3JH2E started cold; was an unreliable starter warm. I read the many threads on Yanmar starting. Installed Yanmar relay (129100-77910) following the enclosed instructions. Problem solved.

[marina.alex]

Thanks everyone. Here in Greece, even though every other boat is powered by Yanmar, there aren't really many parts available.

I ended up going to an automotive shop (which was the only one in Preveza and an hour long walk from the quay) and got a solid-state relay made by Nagares.

I had to fabricate a grounding strap that I bolted onto the engine block using one of the bolts of the original relay -- then added the starter switch blade connector to the other blade of the relay. The relay itself is plastic so I zap-strapped it by my alternator wiring harness. A 10 minute installation and it worked like a charm for 25 Euros -- I think he saw me coming but ... when he has the only relay in town and you need it ... what the heck.

Prior to this I had a workaround of taking a female blade connector and put it on the solenoid male blade terminal and then touching it to a 12volt source -- it would crank the engine no problem -- but it is far superior to be able to turn the key and go.

I appreciate all the help.

[dsteinfeld]

After 6 years and about 250 hours, the starter on my Yanmar 4JH4AE engine began misbehaving. It would occasionally do nothing when I turned the key, but would usually start without doing anything else on the second try. Recently it gave up turning at all so it was (past) time to do something about it. While other posts in this thread discuss this (and related) engines' problem of insufficient current to pull in the starter solenoid, I was reasonably sure this wasn't the case here since the starter battery voltage dropped when the key was turned, and continued to drop if the key was held in the start position for a few seconds. According to the parts catalog, the starter has 2 positive and 2 negative brushes so I decided to check those first, thinking that perhaps one of them was hung up in its holder.

Removing the starter was pretty easy. I have a dual-circuit battery switch that simultaneously connects the starting battery to the engine and the house bank to the electrical panel. As I wanted to leave the house on, I disconnected the starting battery positive cable. However, as we'd just finished motoring, the system voltage was still slightly above nominal and so the automatic combining relay was still pulled in. This meant that the engine was still being powered from the house bank. Disabling the relay removed power from the engine. Despite this I still disconnected the negative cable from the engine first. On my installation the negative battery cable is connected to one of the starter mounting bolts, so this came out first. I then removed the nut holding the positive cable on the solenoid, and the 5 or so wires that feed +12 to various engine circuits. There was also a single wire with a faston connector that I removed from the solenoid. The 2nd mounting bolt was a little harder to reach, but an extension on the socket wrench took care of it.

Once out the starter and solenoid were a lot smaller than they looked installed! The rear cap of the motor is held on with 2 through bolts and 2 small screws. The small screws hold the brush holder to the cap, and the through bolts hold the cap on and the entire motor assembly together. When all 4 fasteners are removed you can remove the cap, sliding the positive wire insulator out of the cap. Note that with the through bolts removed, the motor wants to push itself apart due to the various internal springs. I basically held the parts together for this first inspection. I found a fair amount of metallic particles in the cap, so I expected to see worn brushes. Instead it appeared that there wasn't much wear, and by pushing the brush springs aside and moving the brushes up and down it looked like they were fine in their holders and were making good contact with the commutator. However the commutator had a lot of gray residue so I decided to burnish it.

Getting at the commutator was a bit difficult since there are 4 brushes and their holders. 2 are negative and have copper braid that's riveted to the brush holder. Note that this means that if the negative brushes are worn you need to replace the entire holder assembly. There are 2 positive brushes that are wired together to the lead that exits the cap and connects to the solenoid, so removing these from their holders made room to get to the commutator. Removing the brushes is as simple as pushing their springs out of the way and sliding the brushes out of their holders. However the entire starter still wants to push itself apart, and getting at the commutator is still difficult.

The motor separates from the gearbox almost by itself, with a spline shaft on the armature that simply slides out of the gearbox section. However the gearbox still wants to push itself apart, probably from the spring that retracts the bendix gear. Rather than let it fly apart, I used a long nose vise grips to hold the gearbox together. Once the gearbox is taken care of, the outer sleeve of the motor (which holds permanent magnets) can be slid off the armature, leaving the commutator pretty accessible. While removing the brush holder from the armature would make the job go easier, there's a large clip (sort of like a c-clip) that keeps it in place, and I didn't see a good way of replacing it without buggering the shaft so I left it in place. I burnished the commutator using the space between the 2 positive brush holders, and even with restricted access it only took a few minutes. Reassembly was in reverse order, although it was easy to get the motor and gearbox misaligned, making putting the through bolts in difficult. There are several parts in the gearbox that need to be aligned, and then the end cap needs to be aligned with those. Making sure that all is aligned before engaging the motor in the gearbox and putting the end cap on makes this relatively easy though. Also, the brush holder has to be aligned with the end cap so that the 2 small screws engage in their holes. The screws aren't that long, so the brush holder has to be back far enough on the motor shaft so that it's close enough to the cap.

Installation is the reverse of removal, albeit with a small issue: you really want to connect the negative cable last, however (at least on my engine) as this is one of two mounting bolts you're tempted to do it first. I screwed both mounting bolts in first but left them untightened. I reconnected the positive wires and the positive battery cable. The torque spec for the positive terminal is 65-87 in-lb, which was below the range of my torque wrench, so I just guessed. Once this was on I removed one of the mounting bolts, connected the negative battery cable, and tightened both mounting bolts to 65 N-m (78.2 to 98.2 N-m derated 80% when tightening to aluminum alloy).

After reconnecting the starter battery the engine failed to start! Then I realized I'd forgotten to reconnect the black wire from the ignition switch and relay to the solenoid! Once that was reconnected the engine started on the first turn of the key, and has started first time since.

My apologies for not taking photos of this small project, but I hope this narrative helps someone out.

[Thanna5]

Many thanks to the posters on this topic. I've had electrical gremlins for several years after salt water spray hit my port Yanmar 4LHA-STP. The starter and solenoid have been intermittent and would engage only with a "boost" from a charger or battery pack. I added the relay into the system as described in this forum, and now have like new starting on this engine. Lots of scrapes from poor access, but a big smile. Thanks all. Capt. T Hanna

[D.C.Y.]

I too am experiencing this same issue. Will simply replacing the solenoid give me a worry free season?

[jdy2kgt]

Originally Posted by kiltym

The relay part# I use:
Tyco
12V
V23234-A0001-X032

There are 5 pins on the relay:

87 - Jumper to starter male spade terminal
86 - Wire from Yanmar panel (used to go directly to starter)
30 - Positive jumper from large positive cable attached to starter.
85 - To Ground
87a - Not used


So, without this relay, you have 1 large nut on your starter, with a rather thick positive cable on it (this should come from your start battery). And, you should have 1 smaller cable, with a spade female disconnect on it that is connected to a spade post on the starter (this will come from the Yanmar engine panel at your helm station).

You need to remove this wire from the spade on the starter, connect it to position 86 on the relay. Then you make two short runs of cable, one going back to that spade male terminal on the starter from position 87, and another one from the big nut/positive cable on the starter to position 30 on the relay. Then a short ground wire to your engine ground from position 85 on the relay.

I'm not sure what went wrong here. I followed the directions provided and hit the start button. The starter came to life like it never did before but it didn't sound right and certainly wasn't turning over the motor. I'm using a 12v30A relay. I took everything back apart and reconnected the white wire to the spade on the starter and sure enough after pushing the button a few times motor fired up like always.
Can you look at the video and tell me what I might be doing wrong?