# Yanmar 2QM15 Rebuild



## dreuge (Sep 18, 2009)

Hi,

In early July, I came to my boat after being away for three week and found the engine seized. It was locked up solidly, in that it would not budge even a little bit after soaking the cylinders with Marvel Mystery oil for several days. It turned out to be a blown head gasket which let salt water into a cylinder.

I hauled the engine out with the boom and rebuilt it for a cost of only parts and machine shop work. The engine is back in and is working great. I have posted photos online if anyone is interested.

Yanmar 2QM15 Rebuild - a set on Flickr (www.flickr.com/photos/dreuge/sets/72157631067396554/ ) 

Unless you live near a Yanmar distributer, knowing which part numbers to order can be time consuming and costly. I include my list below in order that it may help someone down the road.

My total cost was about $825.

*Machine shop work*

Cylinder head work $300
Honing piston rod bushings to fit piston pins $40

*YANMAR 2QM15 PARTS*
Price quote from Mastry Engine Center


Gaskets
head gasket (124060-01331) [$28.79]
valve cover gasket, o-ring type bonnet (124060-11311) [$8.47]
oil pan sump gasket (124060-01743) [$16.26]
exhaust manifold output gasket (124701-11911) [$9.15]
exhaust manifold Adj. gasket (124770-13131) [$1.87]
exhaust flange gasket (124770-13171) [$27.43]
engine zinc cover gasket (124450-11681) [$1.53]
thermostat gasket (104211-49160) [$1.36]
exhaust manifold forward flange gasket (124770-13181) [$9.00]

Engine parts
piston rod bearings (124060-23300) [[email protected]$13.38]
piston w/ rings (724060-22722) [[email protected]$86.37]
piston pin bush (124060-23910) [[email protected]$5.08]
cylinder liner (724070-01900) [[email protected]$111.77]

Other Parts
zinc (27210-200300) [[email protected]$3.60]
zinc packing (23414-250000) [[email protected]$0.85]
thermostat (124770-49200)  [[email protected] 27.10]

Misc. item
Lubriplate #105 assemble lube 
(coating piston, rings, piston pins, bearings) ~$7
Copper Cote gasket spray 
(for head gasket and copper exhaust gaskets) ~$5
Permatex form-a-gasket #2 
(gasket dressing for other gaskets and hoses) ~$4


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## RichH (Jul 10, 2000)

Ya did good!!! The QM series can easily make it to 10,000 engine hours, even if rebuilt.


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## Bradhamlet (Nov 8, 2002)

Nice going my 3GM rebuild was $3,000. However there was more than just a cracked head, there was much welding to do. Any way Yanmars are great, fuel sipping powerful moters.
Brad 
Lancer 36


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## Beersmith (Nov 5, 2008)

nice! I am doing the exact same thing with my 4JH2E.

Documenting the whole process in my blog (see signature for link)


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## Beersmith (Nov 5, 2008)

for those who are looking for parts manuals (service manuals have been posted here many times), join Boatdiesel.com; they have the parts manuals for download.


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## dreuge (Sep 18, 2009)

Beersmith said:


> for those who are looking for parts manuals (service manuals have been posted here many times), join Boatdiesel.com; they have the parts manuals for download.


Yes, I did look there, but I could not find a parts manual for the 2QM15.


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## dreuge (Sep 18, 2009)

I want to add another point regarding Yanmar exhaust mixing elbows.

The 2QM15 service manual lists the part numbers for the two mixing elbow options(see pages 11-10 & 11-11) . Part number 124070-13500 is for the downward angled elbow. The U-type mixing elbow option is part number 124070-13520.

The Yanmar list price for the part number 124070-13520 is $186.26. There is an option for a cheaper (both price and part quality) yanmar mixing elbow. Yanmar part number 128270-13600 which lists for $147.16.

I was reluctant to go with the cheaper mixing elbow because I was told the cheaper one last only a year before needing to be replaced, and in the long run one can save $$ getting the better unit.

I search around and found that HGE manufactures the the better U-type mixing elbow. The part number is HGE3520. One can buy it online for about $70! 

See "www.mmiseattle.com/e/manifolds_e_hge_yanmar.htm" or "bpi.ebasicpower.com/c/YAN-D-EXH/Exhaust%20Parts%20for%20Yanmar%20Diesel%20Inboards". 

I purchased one from MMISeattle (great folks), and it came with a 3 year warranty!


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## Banjo boy (Jan 13, 2013)

Great job! I'm doing a similar job on my 2qm15 and am using your parts list! Thanks! I am needing sending units for the water and the oil. Do you happen to have the part #'s for those items?

Again, great job. I hope I can do the same.


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## dreuge (Sep 18, 2009)

Sorry, I don't know these numbers. My guess is that they are standard. The only concern would be to see us the temperature sends differ for raw water cooling versus a fresh water system.


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## casey1999 (Oct 18, 2010)

Dreuge,
Thanks for great post. I have a similar set up with a 30 year old Yanmar 3GMD and will be looking at having to do the same in the not to distant furture I am sure.

Did you notice any changes in exhaust or operation before the engine siezed up? 

I get some white exhaust (steam?) when I run my direct sea water cooled engine and am wondering if it is sea water entering the cylinder through a bad head gasket. Thinking maybe somtime soon I should pull the engine and spilt the head and block, clean all the cooling passages, replace head gasket. 

Also, I have been flushing with fresh water after use, maybe buy a little more time out of her.

Regards


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## dreuge (Sep 18, 2009)

One sign was that the engine was a little hard to first start when cold (weather in the 60s and below). And within the month before she froze up, I noticed the engine oil was a just a tad bit lower than usual. All understandable in hindsight.


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## weephee (Oct 25, 2008)

I just purchased a 2QM15 to replace the Atomic 4 in my boat. I received the Parts List and the Service manual with the engine (1977) To answer Banjo Boy's request for part numbers this is what I have;
Oil Sensor 124060-39451
Coolant Sensor 46150-004530 replaced with 127610-91350 (200 degrees)
Hope this helps


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## casey1999 (Oct 18, 2010)

How hard was it and how do you get the cylinder liners out of the block? Looks like these could get rusted in.
Thanks


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## dreuge (Sep 18, 2009)

casey1999 said:


> How hard was it and how do you get the cylinder liners out of the block? Looks like these could get rusted in.
> Thanks


It was pretty easy removing both cylinder liners. You can buy or easily make cylinder liner extractor. I made mine from a threaded rod and scrap Aluminum.


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## casey1999 (Oct 18, 2010)

dreuge said:


> It was pretty easy removing both cylinders. You can buy or easily make cylinder extractor. I made mine from a threaded rod and scrap Aluminum.


Are you refering to removing the cylinder or the cylinder liner with this tool?
Regards


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## dreuge (Sep 18, 2009)

Yes, Cylinder liners.


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## mstiles (Sep 20, 2002)

If you don't mind me asking, where did you end up buying your Yanmar parts?


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## dreuge (Sep 18, 2009)

I called and had them shipped via UPS from Mastry Engine Center.

Mastry Engine Center
Welcome to Mastry Engine Center
Toll Free: 1-800-545-4574

2801 Anvil Street North
St. Petersburg, Florida 33710


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## casey1999 (Oct 18, 2010)

Dreuge,
Where the fuel injectors go into the head, there are several washers, packing, and an o-ring. It looks like you may have removed these to clean the head. Did you install the old or install new? If you took these parts out, was that difficult?
Regards


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## Ship 609 (Jun 15, 2015)

Hello Dreuge, if you're still in SailNet and particularly if still in NW Florida, I'd love to chat some more about your 2QM15 rebuild. We have that engine in one of the boats in my Sea Scout (BSA) unit and we managed to overheat and seize it.

If you read this, please look us up via our web site Sea Scout Ship 609 - Pensacola, Florida

thanks


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## zacorrig (Oct 14, 2015)

This is super helpful. I'm considering a rebuild of my 2QM15 in this off season. The previous owner did not do any professional work on the engine and she's in need of some serious care. Looking at your photos was this done on a Seidelmann 299 by chance?


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## dreuge (Sep 18, 2009)

zacorrig said:


> This is super helpful. I'm considering a rebuild of my 2QM15 in this off season. The previous owner did not do any professional work on the engine and she's in need of some serious care. Looking at your photos was this done on a Seidelmann 299 by chance?


The 2QM15 rebuild was on my C&C 29 mk1. I had since sold the C&C 29 and purchased a C&C Landfall 38 which came with, though not actually in the boat, a Yanmar 3Q30 which needed a rebuild.

See my blog for details of the 3QM30 rebuild:

S/V Johanna Rose: Engine Rebuild


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