Exhaust planning...6LYA 370 Turbos 12,000 hrs. 4BT 33,000 turbo

BillD

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FWIW, I'm posting some pictures of "dry turbos". Turbos that had exhaust systems designed and installed from hour #1 to keep ALL sea water out of the exhaust side of the turbos.

Height above the waterline and gravity are a "must".

Here are some pictures of two Yanmar 6LYA 370 turbos after 12,000 hrs.
This turbo has "seen" ZERO water.

The turbo on the 4BT (used as a generator) has 33,000 hrs. It's never seen a drop of water.

Yanmar 6LYA 370 Turbo --12000 ++  hours  (1).jpg

Yanmar 6LYA 370 Turbo --12000 ++  hours  (2).jpg

Yanmar 6LYA 370 Turbo --12000 ++  hours  (3).jpg

Cummins 4BT Turbo 33000 + hours (1).jpg

Cummins 4BT Turbo 33000 + hours (2).jpg

Cummins 4BT Turbo 33000 + hours (3).jpg

Cummins 4BT Turbo 33000 + hours (4).jpg

Cummins 4BT Turbo 33000 + hours (5).jpg

Cummins 4BT Turbo 33000 + hours (6).jpg
 

djmarchand

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Bill:


What was the usage history on the 12,000 hour Yanmar 6LYs. I'll bet that is one of the highest hour 6LYs out there. Tony Athens got about 11,000 hours on his brother's commercial fishing boat on his 6LY before repowering recently.

Any evidence of them getting tired- blowby, hard starting, etc.


I don't doubt that anyone can get that many hours from a 6LY but it takes good installation, maintenance and running them at a reasonable load to do it.


David
 

BillD

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Bill:


What was the usage history on the 12,000 hour Yanmar 6LYs. I'll bet that is one of the highest hour 6LYs out there. Tony Athens got about 11,000 hours on his brother's commercial fishing boat on his 6LY before repowering recently.

Any evidence of them getting tired- blowby, hard starting, etc.


I don't doubt that anyone can get that many hours from a 6LY but it takes good installation, maintenance and running them at a reasonable load to do it.


David

The engines are out of Tony's brother's boat. 13,000 hrs. when taken out.

Yanmar 6LYA 370--just under 13000 hours (1).jpg

Yanmar 6LYA 370--just under 13000 hours (2).jpg

Yanmar 6LYA 370--just under 13000 hours (3).jpg

Yanmar 6LYA 370--just under 13000 hours (4).jpg

Yanmar 6LYA 370--just under 13000 hours (5).jpg

Yanmar 6LYA 370--just under 13000 hours (6).jpg

Yanmar 6LYA 370--just under 13000 hours (7).jpg

Yanmar 6LYA 370--just under 13000 hours (9).jpg

Yanmar 6LYA 370--just under 13000 hours (10).jpg

Yanmar 6LYA 370--just under 13000 hours (11).jpg
 

BillD

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here's three more pictures of the 6LYA 370 with 13,000 hours.

and five pictures of the 33,000 hour 4BT used as a generator for the boat.

all three motors look pretty good for all the year round hours on a commercial boat.

Yanmar 6LYA 370--just under 13000 hours (8).jpg

Yanmar 6LYA 370--just under 13000 hours (12).jpg

Yanmar 6LYA 370--just under 13000 hours.jpg

4BT 47Kw Aux--33000 hours (1).jpg

4BT 47Kw Aux--33000 hours (2).jpg

4BT 47Kw Aux--33000 hours (3).jpg

4BT 47Kw Aux--33000 hours (4).jpg

4BT 47Kw Aux--33000 hours (5).jpg
 

djmarchand

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After all I have read about those engines on boatdiesel, I feel like I am looking at an old friend or maybe a museum piece.

My relationship with them goes back to 2005 when Tony had just installed them on his brother's boat. I was looking at a new Mainship 34T with either the Yanmar 370 or the new Cummins QSB but at a big price difference for the QSB. Tony convinced me that the price difference was too much and that the Yanmar would do a good job, and it did. I lusted after that custom high output alternator that is installed on one of those engines.

Later I bought my current boat, a Mainship Pilot 34 and it also has the Yanmar 6LY 370. Tony's boatdiesel input on exhaust system design and aftercooler maintenance let me correct a poor exhaust design and catch up on some deferred maintenance.

David
 
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chortle

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Impressive photos of the turbos. Why did they replace the engines?
 
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