Raw water system flushing - Yanmar 4LHA-STP

[fgutierrez10]

Has anyone had any experience using acid based products to flush the raw water system (e.g., RydLyme, Barnacle Buster, others)? I am getting mixed messages re. benefits as a once-a-year maintenance approach to prevent growth in the system vs. metal/gasket damage that the acid can create.
Any opinions/experiences will be highly appreciated. Thanks

 

[Comodave]

I have used BB in the past. I used the sit and soak method for about 6 hours. One engine dropped 5 degrees and the other engine dropped 10 degrees.

 

[Cigatoo]

Has anyone had any experience using acid based products to flush the raw water system (e.g., RydLyme, Barnacle Buster, others)? I am getting mixed messages re. benefits as a once-a-year maintenance approach to prevent growth in the system vs. metal/gasket damage that the acid can create.
Any opinions/experiences will be highly appreciated. Thanks

I used Barnacle Buster in my Yanmar 4LH with good results. I called BB directly beforehand. They assured me there would be no issues FWIW.

 

[DavidM]

I wouldn't do it yearly as it does corrode the metals a little. But every 5 years would be fine. I wrote an article on how to do it on my Yanmar 6LY. The 4LH should be similar. It is in the Library section of this forum. Click the icon on the upper right of your screen. I think it is in the Misc subsection.

David

 

[Cigatoo]

I agree with David. Once it is cleaned with BB flushing for a 1/2 hour at end of season will go a long way with keeping it clean.

 

[Easternshore]

We recently flushed both Yanmar 4LHA-STP engines on our MS Pilot 34 as part of a 250 hour maintenance, she has 500 hours. We used a fernco 3”-2” reducer to fit into the raw water strainer, ran about 4-5 gallons in each engine and let them sit for 6-7 hours. Was surprised at how much “stuff” blew out of the exhaust, both engines run cooler per the gauges.

Local Yanmar dealer said to flush every 250 hours.

 

[fgutierrez10]

Thank you very much everybody for your replies and comments - I am planning on using BB on my Yanmars

 

[rgano]

Barnacle Buster's bottle I have says to run the solution continuously for a hour. I am doing a lot more frequently than 250 engine hours because my usage is not very many hours annually. The solution was still pretty murky even after 136 hours.