Yanmar seawater exhaust bleeder plug

[Dalestr]

Try to get alignment within .003" between the metal half couplings then reinstall Drivesaver. My 2 cents on these brake bleeder types drains is leave as designed. This has straight threaded port so not easily "PLUGGED". Your exhaust hose is 1-5/8" and that is fine for this 15hp engine but as stated by others, the muffler should be on the same side and close to the engine exit. When possible, replace copper elbow with straight barb fitting, SS preferred, 1.25 BSP thread to 40mm barb. Available online. Yanmar uses British pipe threads and they're not compatible with NPT.
You apparently need a very thick shim under some engine mounts and this should become one with the beds at least by epoxy means if not fiberglassing. Lots of forces here. If wood, could use medium hard wood, epoxy sealed, or solid glass like G4. Extra length mount screws needed. The siphon break valve if needed should locate high and the drips, when it needs cleaning, are clear of engine.

[maury]

To group: So I am planning the modification discussed in the near future once I have the funds for parts. As I start to look at it more closely I will have questions.
Maury

[capt jgw]

Originally Posted by SY Harmony

In the pic attached, I marked an area in blue.
When you tighten the fitting into the end cap. The blue area seat against the end cap and seals water flow off.

I would KEEP the fitting over a plug. Simply because of the hose barb! That allows you to control the outflow of raw water when you have to drain it. This keeps your engine from getting a salt water bath.

Yes. I believe there is another part inside the cap that this piece butts up against and shits off the flow. Unless that other part is broken or missing. Take the cap off and you'll know. You need to check the tubes inside there periodically anyway, they can get clogged up.

[nofacey]

Screw your drain plug all the way in, put the drain hose back on it, and start the engine. It should seat & seal when snug, bleed when loosened.
- replacing with a plug likely reflects the mechanics opinion on it ever being used.

Don’t worry about cast iron comment - most marine engines use cast iron extensively. Do take a look at your manual to see if there’s any zincs in the coolant system you should be replacing annually.

[nofacey]

Your exhaust system is totally ****ed and risks ruining your engine by flooding it with saltwater a couple different ways.
- you need a high vented loop on the saltwater feed to your mixing elbow, and have to get rid of that high loop in the blue hose between the engine and the water lift.
Take a look at p19 in the attached Vetus manual, it shows what we’re talking about
https://vetus.com/wp-content/uploads...-UIT3090-1.pdf

There’s a ton of conflicting opinions on the Internet….go to manufacturers install manuals when you’re confused.

[SY Harmony]

@maury

Going back to this pic.
What I would do is as follows.
1) disconnect both hoses from the water lift muffler.
2) turn the muffler 180*
3) rerun the blue hose to the muffler and shorten as necessary. So it is a direct drop into the muffler.
4) Use the excess to creat an extension to your current outlet hose. Running that along the top of the bulkhead and drop it onto the muffler.
5) fix the vented loop situation.

[maury]

So looking at all possibilities immediate and short term:
ST: Disconnect muffler for now and go mixing elbow to exhaust. By the way the 90 degree elbow is bronze connected to mixing elbow. I might need to find a simple piece of pipe to connect the two hoses for added reach..
LT: Could I add an extension to the mixing elbow to raise it 6-8” higher? This would give me good drop to the exhaust in its present location, possibly turned around as sv Harmony describes in prior comment.

[Icarus]

Originally Posted by Turtle Blues

Pressure close to 20 psi possible
Bolt with hose clamp ok for temporary.

Not at the raw water cooling circuit.

[SY Harmony]

Originally Posted by maury

So looking at all possibilities immediate and short term:
ST: Disconnect muffler for now and go mixing elbow to exhaust. By the way the 90 degree elbow is bronze connected to mixing elbow. I might need to find a simple piece of pipe to connect the two hoses for added reach..
LT: Could I add an extension to the mixing elbow to raise it 6-8” higher? This would give me good drop to the exhaust in its present location, possibly turned around as sv Harmony describes in prior comment.

It’s hard to tell from the pic.
What is the vertical separation between the 90* at the engine and the inlet of the muffler?
Which is higher?

[maury]

“It’s hard to tell from the pic.
What is the vertical separation between the 90* at the engine and the inlet of the muffler?
Which is higher?“


They are equal.

[maury]

So when I measure the exhaust elbow the water line with present boat load would be about an inch from the top of the exhaust elbow or full boat I assume would be underwater.

Now yanmar illustration (next post) shows a small 8” hose going to the exhaust elbow whereas vetus shows a loop above waterline. How does one balance these scenarios.

[maury]

Yanmar Hose to exhaust elbow about 8”

[SY Harmony]

The yanmar illustration is a basic install, likely in a small skiff/fishing/work boat. Because you’re so close to the water line. Play it safe and install the vented loop.

Now, regarding the large exhaust. If the outlet is on the same vertical plane as the inlet to the water lift. Just run a short hose directly between them. IIRC, Vetus make a 90* inlet fitting.
You’ll get the needed separation internally. How? Measure from the internal apex of the exhaust u-bend. (The wall the water has to climb to back flow into the engine). Down to the bottom of the muffler. Then subtract the height of the “pinch point” in the muffler.
I’m guessing that’s 8-10” from the pics. It’s not “to spec”, but it’s as good as it gets in your hull.

[nofacey]

Originally Posted by maury

So looking at all possibilities immediate and short term:
1) ST: Disconnect muffler for now and go mixing elbow to exhaust. By the way the 90 degree elbow is bronze connected to mixing elbow. I might need to find a simple piece of pipe to connect the two hoses for added reach..
2) LT: Could I add an extension to the mixing elbow to raise it 6-8” higher? This would give me good drop to the exhaust in its present location, possibly turned around as sv Harmony describes in prior comment.

1) it’s not a muffler, it’s a water lift - it gathers the water that’s injected into your exhaust line at the mixing elbow, and boosts it up & out of the exhaust line. Do not take it out!
2) that’s a great idea, if you truly need to get more vertical separation between the mixing elbow and the water lift inlet.
- must be metal,( I’d use a 316ss pipe nipple) as this is before any cooling water is injected = hot enough to melt rubber.
- check the threads before you ram anything to the mixing elbow to ensure they match
- use a high temperature pipe dope when putting them together. Exhaust leaks are dangerous
- once it’s together and every thing looks good, you’ll want to insulate the new pipe, as it will run burning hot. Easy to wrap in exhaust insulation tape with SS wire holding it in place.

[skipperpete]

Originally Posted by maury

Attachment 278448



Yanmar Hose to exhaust elbow about 8”

Maury, there’s a mixture of wise information and and “ not so much” coming at you here. Your suggestion to raise the mixer is unwise, that little engine is fairly lively at some rpm settings and the load on the exhaust manifold will be a problem.... you could do it with a couple of supports but it needs a bit of planning. We still don’t know if your engine is above or below your boats WL but the hose (#24) that you identified in the Yanmar page is the one that needs to be extended to accept a siphon break if you choose to do so.
The consideration regarding the blue hose is “ where does the water go” at shutdown or cold cranking after a fuel supply problem. Normally all the drainback is contained in the Aqualock but that blue hose is pushing the friendship a bit.