Maintenance

[brian sutton]

New to diesels so looking for advise.posting some pics of turbo and mixing elbow.

1) Does the tubo look like its time for tubo wash?

2) Are their other areas of the turbo I should be looking at?

3) Any comments on the mixing elbow?

Yanmar 4lh, 600 hrs.

Thanks, Brian

Topic

[Bill Fuller]

Hello Brian,

It looks like you are 100% on top of everything.  Your maintenance schedule is almost identical to mine and is what I would recommend.  The aluminum exhaust manifold is one of the few weak points in these engines and is very sensitive to coolant.  Consequently, for the cost involved, I simply change my coolant every year.  That’s 17 years now. You might want to adjust the valves.  Yanmars calls for every 600 hours.  Especially if they have never been checked. There has been some confusion as to the valve lash spec in the manual, at least early ones, gave 2 different clearances for the exhaust valve lash.  If you come across this, use the larger clearance. I think, but don’t quote me on this, intake at 0.1mm (0.004 in.) and exhaust at 0.5mm (0.020 in.).

I think your turbos look fairly good. Just a little surface rust, probably from condensation during the winter layup. The “turbo” wash does not really do much of anything to the turbo itself.  What it does do is sort of steam clean the air side of the after cooler and maybe dissolve some carbon deposits off of the tops of the pistons.  Use about 1 table spoon of Dawn in 8 oz. of  distilled water and then follow up with 8 oz. of pure distilled water.

As for fuel additives, I use Bio-Bor when the boat is not being run multiple times per week, during the winter. In the summer I don’t normally use anything.  These days, I typically change filters once a year, which has been averaging about 600 hours. But this all depends on the quality of the fuel you purchase and the cleanliness of your tank. I use the primary filter that was provided by Yanmar which turns out to be a Racor model 490.  You might want to look it up.  I use a 10 micron cartridge and the on-engine filter is 2 micron. I love the pump on the model 490.  put everything together dry, pump the fuel up with the push button pump on the filter until the on-engine filter is full, and start the motors.  If they are running rough just keep pumping until all the air is out.  So easy!! I have never cracked in injector!

I do not use any corrosion preventer on the engines.  Just try to keep them dry and painted.  I do wash them off occasionally with fresh water.  The best thing to do is to be sure to keep the engine compartment warm to prevent condensation on the engines. I have 3, 100 watt light bulbs in my bilge which does the job.

I will take some pictures of my motors and post so that you can see their current condition after 17 years and 5,100+  hours.

Bill

 

[brian sutton]

Follow up

Thanks for the replies,

1) I believe the motor is  a 2011-12? 4lha-stp

2) heat excganger,air cooler,oil cooler and gear coolers were removed,end caps taken off and cleaned last fall.Pic of trans cooler is provided.

3) I keep a close eye on zinks and change as needed.

4) lm useing Prestone dex-cool aproved,extended life coolent and changed it after one season.

5) I change the raw water impeller yearly.

6) I installed a fresh water flush this spring.

7) Trans- ZF 63A-1.6, ratio 1.56:1,change fluid yearly.

8) primary fuel filter,racor dual w/30 micron eliments.

9) belt is checked and adjusted often.

10) 4 blade prop-original rpm 3175 ( photo tach) repitched to 3300,repitched again and should get 4300-4500 rpm.

11) installed aetna tach.

12) have Not had the valves adjusted,873 hrs.

Note: I put around 200 hrs on boat yearly, 1/3 wk end getaways and 2/3 fishing GBT (giant bluefin tuna).Have not done any slow trolling (yet).

The cofiguation of exhaust has not changed although elbows were replaced with 316 ss.

The lower side of mixing elbow is about 13″ obove water line.Also a Centec FRP acoustic silencer is installed.

 

Q: does my turbo look like it needs to be turbo wased? What do you clean your turbo with?

How often so you change coolant,can you get two years out of it?

Do you use any fuel additives,I do not have access to look inside fuel tanks but have not had any signs of water or any filter fowling?

Do you use any type of corrosion guard on entire motor?

Thank You,

Brian

 

 

 

 

[Bill Fuller]

Hello Brian,

Welcome to the world of the Yanmar 4LHA.  One fantastic little motor.  As Tony indicated you are pretty much on top of the basics as to engine longevity.  I will ask a couple of questions and provide a few of my thoughts.

Maybe you could tell us a bit about your boat, brand etc., and how you use it.  Also maybe some pics of the boat.

What year are the motors?

Have you removed the end plates on the heat exchanger and oil cooler to take a look inside? 

Also have you had the after coolers apart for service?

What gear cooler do you have and have you serviced it?

Have you changed the zincs and how often? At layup time? In the spring?

What coolant do you have in the motors and how often do you plan to change it?

How often do you change the water pump impellers?  In the spring?

Have you installed a fresh water flush system yet?

Have you done a valve adjustment?  If it has not been done then it should be at this point.

What transmissions do you have and have you changed the fluid in them yet?

What fuel filters do you have?

How many hours do expect to put on the motors each year?  Oil change frequency?

How often do you check the tension on the alternator belts?

I think I will not make any comments until you have had a chance to contemplate and answer the questions. I believe that I can suggest a maintenance schedule that will fit your needs, and usage and ensure longevity for your motors.

As you can probably tell, I love these motors.  Mine are now approaching 5,200 hours and 17 years with no raw water side failures.  Actually the only failure I have had is a torsional damper (drive plate) which is a ware item anyway.

Bill

[Tony Athens]

Brian, I must say that as you got involved here, I think you got even more involved with what is going on…..Overall, I think you are top of it, realize that what you have is from perfect, have done the best you  can do for the time being,  AND, will do this from here forward………………… WWM——————-Meaning Wait, Watch,  & Monitor.. You are good in my book ( for now) as long as  you do WWM.. How about posting some new pics of the new elbows and their orientation as to “Mother Nature”..?   Tony      

[brian sutton]

I replaced riser and mixer elbows with 316 stainless steel.ill keep a close eye on it.I think its a bad place for cast iron and/or low grade ss when it is sitting idle for 5-6 month.

[brian sutton]

These arw pics after I wiped them off

[brian sutton]

Additional thoughts, I did notice when I took the exhaust hose off the mixer, I inserted a video scope down the mixer and into the riser elbow and noticed it had some damp/wet crud on it when I pulled it out and that was before I started it up after the winter layup (just wondering why it would be damp/wet after sitting for 5 month).

Also if a cracked exhaust manifold from being overheated is causing coolant to enter the turbo,could/would a good coolant cause this kind of rust in say 9 month, the first 3 the boat in use and the rest boat was layed up for winter. Brian

[brian sutton]

Sorry for the upside down pics.

I have read that water can enter the

turbo by,

1) a bad mixing elbow

2) a cracked exhaust manifold ( I dont recall adding coolant last season)

3) a badly designed exhaust system

Full disclsure I did overheat the motor once from not opening seacock (I now have a seperate alarm for that). Any thoughts? I would be happy to provide any aditional info requested.

Thank you,Brian

 

[brian sutton]

More pics

More pics

[brian sutton]

Ok, I have several pics to post.Their does appear to be some moisture getting into the exhaust side of the turbo.Do not believe any water is backing up through the exhaust do to the steep angle exiting the mixer?The obvious place for water to come from would be where the raw water inters the mixing elbow because where it comes in the mixer drops straight down to the elbow that goes to the turbo.Any sugestions would be greatly appriciated.

Brian

[Rob Schepis]

Air side of turbo is nice and clean, no evidence of a “salt air intake”.  Mixing elbow looks a bit suspect.   Like Bill stated, need to to exhaust side of turbo…

[Bill Fuller]

Difficult to reply by cell phone. But pull the elbow off of the turbo and post some good pics of the exhaust side of the turbo.

[Author]

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