Help with engine bay plumbing/exhaust layout, CSY44

[Patrick of M]

Just bought a '79 CSY44.
The engine was already out being rebuilt.
I need to reinstall a Perkins M92.
I have a few pictures of the engine prior, but as I wasn't there during removal,
Pictures of other installations would be helpful..
Also if anyone sees problems with the prior installation, I'm all ears.
This is a new boat for me and I am not finding much in the way of technical documents, so I will muddle
through.
If anyone can point me towards links/sources/supply pictures etc of original wiring/plumbing etc diagrams,
that would be helpful even though unlikely to accurately reflect what I am working with.
Cheers
My pics swamped the post so I will post them separately

[Patrick of M]

Some pics

[Calif.Ted]

I think that engine is of much more recent manufacture than the boat, here is link to installation instructions and a data page. Hope they help.
https://www.maritimepropulsion.com/files/pdf/1001294
https://www.tadiesels.com/releases/P-Sabre_M92.pdf

[Patrick of M]

Perfect timing. This answer came in just as I was trying to download this installation pdf from a very buggy site...
Now I have it!
Thanks bud!

[mvweebles]

Why was the engine out? As someone else noted, maybe a reoower in the past too? Perhaps due to exhaust issues....

I can't tell from the angle of the pictures but the dry riser off the manifold does not look high enough to give 12-inch drop to the lift muffler. Also, the water injection point on the mixing elbow looks like it may not have a good downward angle to prevent water from going into the dry portion of the exhaust and then into the exhaust valves. Finally, out of view, is how the exhaust is run after the lift muffler. It should go well above waterline on all tacks (in case you are motorssailing) with a consistent downward slope to the exit point

See attached diagram

Good luck

Peter

[Patrick of M]

Yes Peter, that was my concern as well. I will definitely be checking the installation against the Perkins guide.
The attached diagram really clarifies the fundamentals.
Thank you.

[mvweebles]

Originally Posted by Patrick of M

Yes Peter, that was my concern as well. I will definitely be checking the installation against the Perkins guide.
The attached diagram really clarifies the fundamentals.
Thank you.

A couple sources:

1. TAD Diesel is a great place for parts. https://www.tadiesels.com/
2. Marine Exhaust of Alabama Marine Exhaust Systems of Alabama, Inc. for custom exhaust elbows. Expensive. But less expensive than the alternative (rebuilt engine).

You would think that builders would install this stuff correctly in the first place, but back in the day, they didn't. Sailboats are especially difficult as the engine is often deep in the hull and getting the exhaust loop high enough is hard. Works fine when boat isn't loaded and the water is smooth.

Unfortunately, my knowledge is school-of-hard-knocks. I have been struggling to get the exhaust right in my Willard 36 trawler for a while. Like a sailboat, the engine is deep in the hull and the decks are low preventing a high loop. My 1970 vintage boat has a 1985 vintage Perkins 4.236. I'm guessing the exhaust was the culprit that caused a newer engine.

Further unfortunately, finding someone knowledgeable in this is very, very difficult. I finally managed to bump into someone who has been with ADE/Northern Lights for almost 20-years who gave me some excellent tips. But he had to physically visit the boat before he was able to give an actionable opinion.

To my eye, you need the dry-loop off the manifold to get more height difference between the injection point and the lift muffler. It does not look like you have room to lower the muffler so you need to raise the elbow. From the lift muffler,, similar to the diagram, best is to go straight up (versus over and up) to above waterline, high enough that you can get slope to the exhaust outlet. One tip I used is to use fiberglass tubing instead of exhaust hose. Being rigid, fiberglass is easier to keep a straight run. I think it's a bit cheaper than rubber hose, but that's only a side benefit. Centek, the folks who make lift mufflers, also make the fiberglass tubing and fiberglass elbows (45, 90, and 180 degree). Better quality than the plastic Vetus parts.

Hope this all helps.

Peter

[Patrick of M]

Peter you bring up some good points here.
My bluewater experience was ith trawlers and their stacks had nothing to do with the waterline.
With sailboats I have always thought a strong following sea, especially with a sea anchor dragging, might force/pump water into the engine if it was not running, especially on this boat( see picture).
I may have to come consider raising the exhaust (perkins asks for 6" above) or installing some kind of backwater baffle.

[mvweebles]

Originally Posted by Patrick of M

I may have to come consider raising the exhaust (perkins asks for 6" above) or installing some kind of backwater baffle.

Here you go - I am told these are maintenance items so you may want to inspect periodically.

https://www.defender.com/product.jsp?id=1656822

A flap on the exhaust pipe works too.

Peter

[Calif.Ted]

What I've found in many sailboats is that rise is accomplished by making a complete 360 loop in the exhaust hose between muffler and outlet. The top of loop comes all the way up to underside of deck on inside of hull. No flappers or check valves required, top of loop always above waterline.

[mvweebles]

Originally Posted by Calif.Ted

What I've found in many sailboats is that rise is accomplished by making a complete 360 loop in the exhaust hose between muffler and outlet. The top of loop comes all the way up to underside of deck on inside of hull. No flappers or check valves required, top of loop always above waterline.

I am picturing a full 360-degree loop, correct? Wouldn't this create a ton of back-pressure; and also potentially store a lot of water in the hose on the engine-side of the loop that could inundate the engine? Sure it keeps the hose above waterline, but it may have unintended consequences......what am I missing?

Peter

[Patrick of M]

Originally Posted by mvweebles

Here you go - I am told these are maintenance items so you may want to inspect periodically.

https://www.defender.com/product.jsp?id=1656822

A flap on the exhaust pipe works too.

Peter

Yeah, flap on exhaust seems a simpler more reliable solution. If that baffle failed closed it could hydrolock the engine, although I guess the flapper could as well, partial blockage might not be noticed right away, engine bogs down, then hydrolock..
Seems to me a floating ball stop in the muffler would work, ..... magnetic sensor as an alarm telltale.....meh, flapper for now.

[kavw]

I’ve only been on one CSY44, but I did work on the exhaust. It had a high rise stainless steel, with a water injection after the loop, then water-box was actually part of the bilge sump aft of the engine, from there it went back up to a loop almost to deck then down out out the side of hull.

[Bellinghamster]

Congratulations, I loved our CSY44 (and still regularly miss her).

I fitted a Perkins 4-236, ran steel pipe dry exhaust (insulation wrapped) well above the waterline and height of the waterlift muffler, injection elbow, downhill to the muffler, then ran hose out of the muffler as high as possible (beside the fuel tank, after of the port lazarette if I remember correctly... it was nearly 20 years ago), behind the head/shower/counter, then tucked up under the aft bunk as high as I could get it, then through a glassed in tube in the transom (I had to increase the size of everything for the larger motor) and fitted a rubber flap on the tube outlet to block any following seas.

The original engine (perkins 4.154) filled up with seawater twice due to clogged vented loop siphoning water into the muffler, so I went full belt-and-suspenders when I replaced it. Having the injection elbow above the waterline prevents any siphon possibility.

A suggestion: Eliminate the cockpit drain seacocks in the engine room and run them out the hull sides above the waterline. This makes working in the engine room a LOT more comfortable, and having fewer underwater holes in the hull improves peace of mind! I also relocated the waterheater outboard of the muffer instead of on the bulkhead mounted shelf above the front of the engine. This made getting around and servicing the engine much easier.



I recently got the content of our old website uploaded and working as a subdomain if you want to read about our CSY 44 refit and Pacific crossing: Imagine Cruising (nav menu on the left side, "The Boat", then "Boat Projects")

[Bellinghamster]

Some CSY44 drawings and construction specifications from my archives: https://app.box.com/s/yt2m9b8urcugzdutnjehd43qu5emb0x3