Yanmar 2GM20C Starter Motor

[Acushla]

This 1990 engine had proved very reliable from commissioning until starting problems started in 2010 (some 20 years of operation but only 600 hours engine operation). The marina electrician decided to change the starter motor (originally a Hitachi S114-303) for an after market starter.
Again in 2011 starting problems occurred and the marina Yanmar agent replaced the starting ring gear on the flywheel and the starter motor, another aftermarket starter. The starter motor gearbox and casting had broken and damaged the ring gear.
Once again in March 2016 the starter motor failed with a broken aft bearing housing. This was replaced with another aftermarket starter which has now failed again in only five months.
All the failed motors with the exception of the original are all aftermarket Chinese made units.
I have been trying to locate an OEM Hitachi made S114-303 to check what is available and at what cost and if possible the engineering differences between the aftermarket product and OEM supply, no luck so far.
Can anyone shed any light on these issues?

[charliehows]

AAE Wholesale Pty Ltd - Starter Motors and Alternators
i got a starter mtr for my 2qm20 from these guys, seems to work pretty well, 2 days delivery to sydney, $450.

[four winds]

Same starter on all the GM series Yanmars. The part number from Yanmar is 128170-77010. Only available from a Yanmar dearer in your local area. Cost is about $400 US.

About the aftermarket starters,.... I think there are several makers of new starters like this. It's a very common design in high production so volume brings the price down. Usually around $80 US just like common auto starters.

I've had much better luck than you with my cheap starter on a 3gm30f Yanmar. Three years now, used daily as a liveaboard at anchor with no problems. (Knock on my wooden head)

There is no good reason this simple starter design should cost $400. I wouldn't be surprised if Yanmar buys them from Hitachi for about 80 bucks.

I think a modern factory using CAD/CAM processes would produce a starter as good as the original regardless of origin.

However you have had more than one example of the "knockoffs" and they have let you down. So it is understandable that you would source an OEM replacement, and the cost would be justified.

Hopefully you don't have some unknown issue elsewhere that would cause even an original replacement to fail early. And I can't think of what that might be either.

Best of luck.

[four winds]

BTW, what was your original starting issue with the factory starter?

600 hours isn't that much use. But after 20 years I suppose there could have been problems related to corrosion maybe.

[hugosalt]

Yes, tell us more about original and ongoing isues.
In many cases with the Yanmar GM series motors
adding a relay to starter solves many a starter problem.
Has been discussed at length on CF and sailnet.

[dgz3]

seems odd to be experiencing actual breakage of castings and housings. Are you sure there isn't some kind of alignment problem? I suppose the original starter is long gone? There usually isn't much wrong them, and they are easily rebuilt or repaired. Provided they aren't actually broken, as your later units are. Same mechanic? Maybe you should change that part next.

[Symphony]

I can't believe a Hitachi starter was defective after only 600 hours. should last 6000 hours. I recently had an intermittent problem with my 4JH4E Yanmar - marina mechanic was talking about replacing starter/solenoid. I found the issue to be a voltage drop in a fuse installed between the key switch and the solenoid (crazy place for a fuse). also found the slide connector to the exciter on the solenoid to be loose. After fixing those two things it was still intermittent every so often... took it off again and found the wire from the solenoid to the starter to be loose enough to be open circuit or arcing every so often.

There are lots of helpful threads on CF, and YouTube is super with direct or indirect help on Yanmar -- just search for Yanmar Tractor engines and you'll find lots of helpful videos.

Yanmar/ Hitachi is damn expensive, but the J-Yen is very strong against just about every currency on the planet. The after-market equipment is made for automotive/ tractor market (slightly larger than the recreational marine market) and so it not spark-arrested or sealed. It will be OK but not last as long, of course there's that big price difference. I was looking at replacing my solenoid: $140 for Yanmar but $25 for chinese automotive exact copy. If you don't mind wrenches and knuckle scrapes it could easily pay to buy the cheap version and replace it every other year.

[DrivinSteve]

May I suggest taking the latest failed starter to an automotive starter/alternator rebuild shop and ask them to opine on the failures.
I find it hard to believe that you had this many "bad" replacements regardless of origin. As others have said, except for corrosion issues, these have a long service life.
Please do keep us posted when you solve the mystery.
Cheers

[skipmac]

Originally Posted by DrivinSteve

May I suggest taking the latest failed starter to an automotive starter/alternator rebuild shop and ask them to opine on the failures.
I find it hard to believe that you had this many "bad" replacements regardless of origin. As others have said, except for corrosion issues, these have a long service life.
Please do keep us posted when you solve the mystery.
Cheers

I will second this recommendation. Very few (if any) starters on "marine" diesels are specially made by the company that puts their name on the engine, like Yanmar, Westerbeke, etc. They are standard starters and any auto shop that does starters and alternators can work on them and usually find a replacement.

[kiltym]

Originally Posted by hugosalt

Yes, tell us more about original and ongoing isues.
In many cases with the Yanmar GM series motors
adding a relay to starter solves many a starter problem.
Has been discussed at length on CF and sailnet.

Here is a link to the CF discussions....

Hopefully of some value, as the problem is quite common.

http://www.cruisersforum.com/forums/...nt-9085-3.html

[Dulcesuenos]

Masco, API, and Arco, all make good starters ,, much better than the cheap poorly made Chinese ones that break the nose cones off causing ring gear damage. One of our masco is 5 years old an works great. Yes probably Chinese but made to a much better tolerance.
http://mascostartersandalternators.c...t_detail&p=167
This is our other one below we replaced about 400 hours ago and works awesome. I accidentally destroyed our o.e. starter after removal to replace an oil line, carrying it off the boat to clean it up dropped it badly .
Or for the non gear reduction unit,. http://www.go2marine.com/product/765...olt-17000.html


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[Acushla]

Thanks a lot for the feed back guys. There appears to be many many after market replacements available for the Hitachi S114-303 varying in output from 1Kw to 1.8Kw some with a cast aft bearing support and some with none. The starters that are failing have an internal planetary gear system in a synthetic material and needs the support of the outer bearing.
Perhaps the non supported versions have a steel gear arrangement?

The last damaged starter is still with supplier under my warranty claim for "unfit for duty" and they have not yet responded to this. I will keep you all informed of the eventual outcome. Thanks again

[DeborahLee]

I went thru the same thing with the starter for my 3GM30F. I finally found a Masco starter and installed it in 2012 it has been great, American made. Cost at that time $229. The through out gear is free floating and is a high speed and torque starter. You can google "Masco marine starters and alternators" to look at them and see if they have one to fit your engine.

[four winds]

Acushla, the original starter only has one gear. The nine tooth bendix drive gear that engages the flywheel.

Sounds like you are describing a gear reduction (higher torque) starter like others have mentioned.

[Boatwright]

Ditto on carefully checking the starter to ring gear alignment/clearance situation. I suggest with multiple failures, including broken parts, that your problem is very likely to be found with how the starter lines up with the ring gear. Starter motors are torquey little devils that will overheat and fail early if misalignment is causing the starter gear to bind on the ring. Tight teeth can cause tooth breakage and a violent jam-up which breaks things. Any good mechanic should be able to check for proper alignment and gear clearance. Maybe this hasn't happened because a cramped engine compartment makes checking difficult. It is unfortunately much easier to throw a new part at a problem than to squeeze into a tight spot and actually check things out properly. Consider the hundreds of times a year you start your car without giving the starter a thought - a properly installed starter, even a cheap one should last a long time in a boat. My Yanmar is running fine after 20 years service on the original starter.