Turbo's on my Yanmar 240's

[Dug]

Some may remember I had to replace my starboard turbo last year.

This year the Port turbo went, same reason, same failure mode.

Evidence points to water ingestion from the outflow side. Mack Boring is indecisive and not very consistently communicative as of now, and my goal is to determine cause to prevent repeat.

At $3000 each, its a bit expensive to repeat every 5-7 years.

Has anyone else either heard of or experienced these issues? Mack Boring is going over a number of rather mundane questions about down angles, etc. Which personally I think is a bunch of hooey because they approved the install at the time and provided warranty as a result of approved commissioning documentation by them at that time. My words are not savory or kind...

So, anyone? Am I solo on this issue? I am not self centered enough to think that I am that special... ;)

Dug

[Rocket]

I have no idea about the marine specific problems with the Turbos Dug, but we have noticed a BIG increase in turbo failures in Cummins motors in our trucks in the past five years. I can't speak for Yanmars, but one thing we changed that has really helped is letting the motors idle for five minutes prior to shut down. I don't know how far you are from inlet to dock or anything about how you operate your boat, but cooling at idle has made a signifigant difference in the amount of turbo failure we were experiencing.

[Harry Woods]

Dug,.
The elbow behind the turbo has a life of five to seven years and costs about five bills. When they age,water backs up to the turbo and the turbos freeze. Remove the air cleaner and see if the turbo rotates freely in both directions. if not, give it a good bath of WD40 and put a wrench on the nut and gently try to move it to the left (loosen direction). This way the worst thing that happens is you loosen the nut and not shear the shaft. If it frees-up you are good to go. Replace the elbow at your leisure. I posted a source in New Jersey for the the entire brand new OEM turbo assembly for the 4LH to someone in PR. It costs about $800 and includes everything but the housing. Glass bead the housing and your floating for a grand.
Harry

[scot]

Dug,

You said your turbo "failed".

How did it fail? Bearings, shaft, seized up, oil seals, blade damage, etc, etc? The answer could make a big difference as to "why" the turbos are failing.

What are the turbo housing made from on the 240 Yanmars?

[Bruce]

Water intrusion could be elbow, water backing up in a med to hard reverse or the distance between the water line and bottom of turbo outlet is too short.
Do your exhaust sit under water or partially submerged?

Shouldn't be to difficult to figure out whats causing it.

[Dug]

Bruce,

No, my exhaust does not sit below water consistently. And there is a good amount of down angle. It has been checked out by my dealer and for whatever its worth the install was approved originally by Mack Boring.

I have a good run from the entrance to the harbor to my slip, so she always idles for a bit.

I am thinking the elbows may be issue. Scot, the exhaust side is caked with rust and the whole thing binds up.

[scot]

Dug,

With 2 turbo failures I would not use the same /existing riser exhaust - discharge set up again. Even if they were the OEM Yanmar pieces. I would have a set of custom SS risers made with the shower head farther away from the turbo... far as you can get it. Maybe a dry set up + wrap + shower head. Main thing is move the location of the entering discharge sea water as far as you can from the turbo.

If you have the space, have the riser fabricators incorporate an "up" pipe, inverted U shaped configuration into the risers to further reduce the chance of sea water getting at those turbos.

Take a look at the risers Harry built for his 6Bs.

Hopefully you will find a solution.

[Bill Fuller]

Dug,

What you have experienced certainly should not be happening. I am in my 14th year with a set of 4LHAs and the turbos have never been touched and are still working just fine after 3,200 hours. I am a firm believer in fresh water flushing, and if you are not doing so, you should probably set up a good and simple fresh water flushing system. Also, listen to what Scott said. This is probably what you need to do. Here is an example of an exhaust system similar to what you need to have built. Scroll down through the pictures.

http://www.sbmar.com/repowers/noelle_ma ... eet_combo/" onclick="window.open(this.href);return false;

When my motors we installed, a dry section was actually welded onto the Yanmar mixing elbow. This has worked out quite well and could be a simpler, easier way to go. Here is a link with some pictures. You would need to start with new elbows.

http://www.sbmar.com/repowers/audax_-_2 ... board_way/" onclick="window.open(this.href);return false;

Another item to think about, if you have not already done so, is to consider removing and doing a thorough cleaning of the after coolers, oil coolers, heat exchangers, and gear coolers. I have done these maintenance items at about 6-7 years and again at 12-13 years. With the fresh water flush that I do religiously, all of the sea water sides of the coolers were quite clean, but all were brought back to "as new" condition. And there was minimal rust and no salt (calcium) built up in the elbows.

Another way to help your issue is to had surge tubes to the exhaust at the point where it turns aft. This would provide a little cushion for water to back up into.

Whatever route you take you need to do something before the water manages to get all the way into the motor.

And do consider installing a fresh water flushing system. It is too easy to do.

Good luck.

Bill

[Charlie J]

dug
as bill said and also you need to check every once and awhile the mixing elbows
they tend to rot out from the inside flange both of mine have been replaced
turbos running fine 2700 hrs on them, now I did it just jinx myself dam it,

[Bill Fuller]

Charlie,

I almost did not post for fear of the Jinx!

Dug,

here is another article you should read.

http://www.sbmar.com/articles/marine_exhaust_systems/" onclick="window.open(this.href);return false;

Bill

[JH_B28]

Dug,

Unfortunately you're not the only one this has happened to. Last year after I bought my B28, I found out that both turbos were shot. I checked the intake side to see if there was rotation and nothing. Long story short....when I took them out there were signs of severe corrosion on the exhaust side..so rebuilding them meant changing out the the whole hot side of the turbo. I ended up buying two new ones from the dealer, which fortunately is a friend of mine and gave me a very good price.

I suspect that the problem was from the elbow (rusted) all the way to the exit at the transom ( thru-hull fitting with flapper broken and no surge tubes or mufflers). So this time i'm going with new mixing elbows and mufflers to prevent water surging up.

If you can build something like what Scott is describing or like Bill's set-up, I strongly recommend it. Its the best i've seen for the 4lh's.




-George

[Charlie J]

when I talked to dug about a month ago he stated that there was not many hrs on these engines
like less then 1,000 hrs, I cant see how 2 turbos crap out with thous hrs
bruce whats your take on it

[Dug]

Just a shade over 500 hours.

[scot]

Many of my thoughts on the riser topic came from a conversation Harry Babb and myself had within the last week, as I am headed into building one. I think Harry nailed it with the risers he built for his 31. Too bad we can't talk him into going into the boat parts fabrication business lol.

The Tony Athens article on risers is excellent, thanks for posting the link.

[John C]

If there is any rust on the back side of that turbo you will need to re think the exhaust.... or you will be replacing again.

[scot]

Dug,

Found this pic of a nice 170 Yanmar riser / shower head set up in an Albemarle 27. This one is completely jacketed.