[David R Flamer]

Interesting post. We have the same engines and recently did a full cooling system service. Included servicing AC’s and HX’s. One of the HX’s was replaced with a new Cummins unit. Since then I have replenished close to an entire overflow container of coolant in both engines. This is after probably 30 hours of run time. They did not leak before this service.

We put a pressure test one one of the engines. No pressure drop.

The oil will get changed soon enough and, as always, we will do an analysis. The oil level has not increased, so I don’t expect to see it there. Nonetheless I am curious to see what it’s going to report.

I am not excited about it, but it may be time to look at the heat exchangers again to see if there are issues.

[David R Flamer]

Joe Monaco wrote:

After I serviced my heat xchangers it took several trips before my expansion bottles stayed fulll. I was sure there was a leak but there wasn’t. If you serviced those recently I bet it will settle down after a few more outings.

Happening to me right now. Pressure tested at 20 lbs all day. Zero leak down. Must take a while to burp out.
Is there any procedure to hasten getting the air out of the system, or do we just run it till it gets out?

[David R Flamer]

We had a lift pump fail (of course port engine so on the outside) and it would create a 2265 alarm consistently.

The engine would start and run at low speed no problem. Most likely because the tank was full of fuel and flow was no problem. I am confident that low fuel level would have created a no start situation.

No issues since replacement of the lift pump.

[David R Flamer]

Copy that Thanks Tony

[David R Flamer]

Hi Corey

I have the same issue. I agree with Tony that the pump should just get replaced (I’ll get Vaughan C to do that)

Nonetheless, I’d like to know which 2 pin connector you are referring to. I’d like to check those connections but I can’t tell which connector is the one

Thank you in advance.

[David R Flamer]

I flush the engines simultaneously. Dock water pressure is pretty decent. Since the very first time I tried it I make sure that there is adequate water flow out the exhaust. I also feel the back of the raw water pumps to make sure that neither are warm. They have never been warm. A am confident that there is plenty of water flow.

I tend to let the flushing procedure go a bit longer (4-5 minutes) to ensure that there is nothing but fresh water in the raw water circuit when shut down. It’s a great feeling to know that the engines are sitting in fresh water for those long stretches between uses in the off season.

Zincs have been lasting me 8 to 12 months.

[David R Flamer]

Yes that is about right.

[David R Flamer]

They are usually on the heat exchanger. Take some good pictures of it and post them, especially the bottom of it. I am sure there is one there and someone can guide you to it.

[David R Flamer]

Thank you Philip. I have this display, but I also have the LCD display in the bottom of the tachs and that is the display I refer to. I will take a pic next time I am on the boat.

[David R Flamer]

Philip

This is an interesting thread. My fuel used does not advance. Is there a secret to it?

[David R Flamer]

Thank you all for the responses and great tips. As it would figure, there is plenty of room on the port side (HX on the inside) but not on the stbd.

Tony, if I don’t service them myself they may make it up to you guys to be cleaned up.

A Happy New Year to all.

[David R Flamer]

I’ve been trying to fresh water flush after every single run. I have just changed the zincs on both engines and was surprised to see that they were in pretty good shape. They were in the engines about one year.

Picture is attached.

[David R Flamer]

When you are committed to the flushing process at end of each run of the boat, and the flushing becomes part of the routine of operating the boat, opening the seacocks won’t be a problem.

Nonetheless, I have two large DO NOT START placards on the dashboard when the seacocks are closed.

Further, when the seacocks are closed, I hang the ignition key off of one of the seacock handles. That way I have to open that valve before I get the key.

It’s a system that does work.

[David R Flamer]

I’ve got QSB 380’s. Where is the sh**ty place the lift pump located?

[David R Flamer]

I’m running 10.5-11 GPH per side at 2,200. 15.5 kts typically

[David R Flamer]

I can’t argue with that

I set up a Y valve with separate shut offs and some braided s/s hose to the valves at the strainers. With another shut off valve on the hose itself it is pretty easy to be smooth with the water flow at shut down. With all of the shut offs, it’s pretty hard to leave something open.

Engine room start and stop switches would be pretty cool for this purpose. It would then be a one-person operation.

Another note: After the engines are flushed, I make sure to shut off the keyed master ignition switch and then hang the key on the sea cock lever. Remembering to get the valves open is never an issue. I also put signage on the bridge at the start switches as a second reminder (or in an emergency if the operator was not me) to get the sea cocks opened before the engines are lit the next time.

[David R Flamer]

I still think you need to close the raw water intake if you want to ensure that fresh water only is introduced in to the raw water circuit.

I rigged up a system where I flush both engines simultaneously. While the fresh water pressure at my dock is pretty impressive, I am sure that I am not supplying 100% of the volume that each engine is drawing.

That said, the engines are not under load. I have checked the backing plates to the raw water pumps during this flush procedure and they do not get anywhere near warm. I am sure that there is plenty of water getting to the pumps.

If someone things otherwise, I am all ears.

My procedure does take two people however. When I am done flushing , the hose valve needs to be shut off at the same time as the engines are shut down or there would be too much pressure in the raw water circuit.

1 user thanked author for this post.

Tony Athens

[David R Flamer]

No, not the best, but it is pretty straightforward to R&R the single raw water pump belt. Oh the whole, the belts for the early design QSB 5.9 are pretty inexpensive. I always have 2-3 sets just in case.

[David R Flamer]

How long are you typically seeing the HX zinc last? They are not super easy to get to. I am in the process of rigging a fresh water flush to the gen to see if we can stretch it out a bit.

[David R Flamer]

Rob, Philip pretty much explained what they do. Philip’s explanation makes perfect sense.

[Author]

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