Waterlock laying on it's side blocks water flow?

vas

vas

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evening all,

odd observation, just checking if others have experienced it!
So I've got this Vetus 45mm waterlock installed on my yanmar 2GMF generator engine. Working fine for the last 5-6 yrs, no issues (other than leaking on the swivelling inlet which was a mater of tightening the collar thing).
Last week after replacing earth wiring to the engine, I tried to start the engine and noticed seawater pressure sensor beeping and extremely little water passing from the heat exchanger to the elbow. Puzzled turned off engine, didn't have time to investigate and left.
Today was my next visit to the boat, had a good look around, all normal, started the engine up again, same thing.
Then noticed that the waterlock was almost flat down , say 30deg from floor., lifted it up, started the engine again, all's fine, masses of water flowing through.

Sort of makes sense, but it's a bit odd, My explanation would be that water in the knocked over waterlock blocks the designed outlet, air/water blocked there, exhaust pressure builds goes back through the heat exchanger and keeps the water from the pump pressurised down there with v.little reaching up to the elbow.
Tests were 2-3min long, exhaust hose ok tempwise, haven't destroyed anything :)
Anyway, plan for today was to remove the exhaust elbow and get it to my s.steel fabricator to modify and create a higher lift one, so done that should have it back on Thursday
After this mod, I may not even need the waterlock tbh as exhaust can go straight to the silencer and then out to the custom stbrd engine underwater outlet.

cheers

V
 
I would not think a water lock on it side would cause a build up of back pressure to affect the running of an engine.

I would look for a blockage.

In fact it the water lock you posted on its side would allow free flow of the exhaust gasses until the water lock was fuller then the water would burp out when the water lock filled up.
 
not quite on it's side, think from being upright (90deg) it was around 30deg, but I think it was rather full from cranking the cold engine without firing up, plus there's the silencer half a meter away which was also half full of water.
No blockage to think off, when putting it all back together, I'll remove and check all three pipe segments, we'll see!

C
 
WLOCKLR.png


The minimum water level is at the slot between the main chamber at the back and the neck just forward of the outlet you the outlet is the nearest port. Even with that full the back pressure of the exhaust gasses would push the water out

When the engine stops any water in the exhaust manifold and pipe plus water between the water lock and outlet will run back into the water that must be expelled on the next start of the engine.
 
vas said:
evening all,

odd observation, just checking if others have experienced it!
So I've got this Vetus 45mm waterlock installed on my yanmar 2GMF generator engine. Working fine for the last 5-6 yrs, no issues (other than leaking on the swivelling inlet which was a mater of tightening the collar thing).
Last week after replacing earth wiring to the engine, I tried to start the engine and noticed seawater pressure sensor beeping and extremely little water passing from the heat exchanger to the elbow. Puzzled turned off engine, didn't have time to investigate and left.
Today was my next visit to the boat, had a good look around, all normal, started the engine up again, same thing.
Then noticed that the waterlock was almost flat down , say 30deg from floor., lifted it up, started the engine again, all's fine, masses of water flowing through.

Sort of makes sense, but it's a bit odd, My explanation would be that water in the knocked over waterlock blocks the designed outlet, air/water blocked there, exhaust pressure builds goes back through the heat exchanger and keeps the water from the pump pressurised down there with v.little reaching up to the elbow.
Tests were 2-3min long, exhaust hose ok tempwise, haven't destroyed anything :)
Anyway, plan for today was to remove the exhaust elbow and get it to my s.steel fabricator to modify and create a higher lift one, so done that should have it back on Thursday
After this mod, I may not even need the waterlock tbh as exhaust can go straight to the silencer and then out to the custom stbrd engine underwater outlet.

cheers

V
Click to expand...
Hi Vas, anything to do with generator exhaust is confusing to me, but have you a water separator and a silencer? I had always wondered if it was possible but I can’t find an example
 
I have circa .6m of 45mm flex hose from elbow to waterlock, another similar length of hose to a silencer (similar thing oblong and ribbed sort of) and then from there a shorter piece to the top of the underwater exhaust box which is also a custom silencer. Thinking of remove one of the two tbh. so no need for a water separator, you can fit one though, Vetus lists them, dunno how much nor the specifics of elevation differences between elbow, outlet, waterline etc.
 
vas said:
I have circa .6m of 45mm flex hose from elbow to waterlock, another similar length of hose to a silencer (similar thing oblong and ribbed sort of) and then from there a shorter piece to the top of the underwater exhaust box which is also a custom silencer. Thinking of remove one of the two tbh. so no need for a water separator, you can fit one though, Vetus lists them, dunno how much nor the specifics of elevation differences between elbow, outlet, waterline etc.
Click to expand...
Is your generator very quiet?
 
well, exhaust is for sure, the thing is that it's not in a silent box or anything as it was in such a sorry state that I scrapped it.
I'm in the process of soundproofing the whole e/r which is not an easy task!
Main problem is that it's an old school 3000rpm generator, so noisy by definition, if yours is a 4pole 1500rpm it's going to be much better noisewise

V
 
I want to add one like this

However there isn’t much room to put it and, as you say, getting information about the heights of installation is very difficult. And headroom in the lazaret is a problem. I also planned to soundproof the lazaret but it’s just too big a job for now.
I did raise the generator a little and placed it on rubber isolation mounts. I think it helped a little but it’s hard to tell. Cutting a plastic tube and fitting a muffler seems so easy but I’m scared it’s going to affect the back pressure to the engine
 
How did the waterlock end up on its side? Was it simply held in place by the hoses, and if so are these perhaps deteriorated and maybe collapsing inside?

(Waterlocks normally have a bracket moulded into them so that they can be bolted in place (e.g. on the end of the one that Rogershaw pictures in post#5, above).
 
Bouba, what type of silencer do you have currently? and is there a soundbox around the generator? where is the outlet (how high above w/l)?

LS, it was resting on a fore aft beam in the e/r, not bolted (now) was till last year, but about to move it, so unbolted it.
as I said I'll check the hoses, but doubt it's that, fairly young and not many hours on them.
we shall see when I put the elbow back together.

cheers

V.
 
Vas, my generator is boxed. The water runs out about half way down the right hand side


It then goes to the waterlock on the left side, which is almost level with the bottom of the generator (it can’t go any lower)


Then it goes to the highest point possible for the water separator


Then to a very short length of hose to the underwater thru hull
 
looks like a better installation than mine Bouba, what is the issue and why do you want to add another silencer? and where? this thing you suggest is rather large, and I think has to be placed horizontal, right?
 
The why is easy the where not so. But you are right, I’ve had many compliments on the generator installation !
I was hoping to put a small silencer just before the the thru hull fitting.
I realise that a silencer is for external noise but I would like it to be a bit quieter inside the boat. Ideally, I didn’t realise it was on, level of noise
 
where do you identify the sound as coming from?
the one you suggest, will have (iirc) be fitted BEFORE the water separator and is indeed to reduce the exhaust noise.
not sure you're going to achieve anything unless you focus on some particular noise when running and try to address it.
how many rpm is the generator?
is water now going under w/l and gasses over?

Since it's in a box you could (theoratically):
a. improve the insulation of the box
b. check how the inlet of fresh air is dealt with and see if that can be improved with traps
c. improve outlet, but if you have a waterlock and a Halyard separator, I don't see what you should be looking at

I know that in here at least BartW and Montemar are sound specialists, I don't think I can suggest anything more I'm afraid!
 
vas said:
where do you identify the sound as coming from?
the one you suggest, will have (iirc) be fitted BEFORE the water separator and is indeed to reduce the exhaust noise.
not sure you're going to achieve anything unless you focus on some particular noise when running and try to address it.
how many rpm is the generator?
is water now going under w/l and gasses over?

Since it's in a box you could (theoratically):
a. improve the insulation of the box
b. check how the inlet of fresh air is dealt with and see if that can be improved with traps
c. improve outlet, but if you have a waterlock and a Halyard separator, I don't see what you should be looking at

I know that in here at least BartW and Montemar are sound specialists, I don't think I can suggest anything more I'm afraid!
Click to expand...
I’m not sure of the rpm, and I just the boat. But the problem is easy, it’s the boat! It’s echoey, it’s not made with much insulation. All sound is very boomy inside. And the next problem is the lazaret where the generator is, it not only takes the entire width of the boat and the entire cockpit but it also runs along the sides. From the lazaret you can crawl along both starboard and port, almost all the way to the bedroom. This makes it a mighty job to soundproof and allows sound to rumble throughout the entire boat. As I’ve said, I already put rubber isolation mounts under the genny. I think that has changed the tone of the noise, it’s a bit easier on the ear. And now I’m looking for another quick cheap fix.
To put a silencer before the water separator would require about two meters of extra hose winding all over the place. So it’s a no go.
As I said you are the only person I’ve heard of who has a waterlock and silencer.
One last question, if I made an additional box to go around the generator box, could that increase the engine temperature to an unacceptable level?
 
Bouba, I'd expect most generators have both a waterlock and a silencer, as with all sailboat engines! it's no scifi, it's a fact.
Maybe you should start by taking the gen soundbox apart and see if you can improve on it.
Building an extra layer of protection on top of the existing protection sounds a bit odd to me...
further, you cannot simply enclose the generator in an extra box (let alone how you achieve this - wont be easy!) you need to leave an inlet for the engine to breath air to the cylinders, many times the inlet roar is rather strong, there are ways to do it though (sound traps, oddly shaped boxes that bolt on the casing and drive air in by deflecting it a few times so that sound cannot get out). There should be such a system already on your box. BTW, what brand/model is the generator (easy to find if it's 1.500rpm or more

ah, and to answer your Q, no it shouldn't as engine is not aircooled and seawater should take that burden.

V.
 
vas said:
Bouba, I'd expect most generators have both a waterlock and a silencer, as with all sailboat engines! it's no scifi, it's a fact.
Maybe you should start by taking the gen soundbox apart and see if you can improve on it.
Building an extra layer of protection on top of the existing protection sounds a bit odd to me...
further, you cannot simply enclose the generator in an extra box (let alone how you achieve this - wont be easy!) you need to leave an inlet for the engine to breath air to the cylinders, many times the inlet roar is rather strong, there are ways to do it though (sound traps, oddly shaped boxes that bolt on the casing and drive air in by deflecting it a few times so that sound cannot get out). There should be such a system already on your box. BTW, what brand/model is the generator (easy to find if it's 1.500rpm or more

ah, and to answer your Q, no it shouldn't as engine is not aircooled and seawater should take that burden.

V.
Click to expand...
I think it’s a
Onan MDKBJ 6KVA @ 2400rpm

Inlet roar is not something I’ve thought about, I will do some research
 
A little bit to add: Back in '84, I fitted a Sailor Silent Set genset to our company yacht. Pulled the Onan, as caked up and corroded. The SSS came in a nice Grp/Balsa laminate enclosure. Engine was a BMW/Hatz driving a Marcon alternator. It had a water lock and a silencer on the output, along with an intake silencer. One could stand next to it and chat normally. In fact, the biggest noise was the water splashing out of the exhaust. It was actually a heap of poo and got nearly to the Canaries when a bolt drifted inside the alternator and wrecked it. They had to fly another one out and were delayed for weeks. That after the voltage reg failed while test running and one was expressed out before they sailed.
But, it was quiet.. Bits were all Vetus IIRR.
 
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