Raw water in engine

[rlea]

Hi, please can you help?
I have raw water in my Perkins 3 cylinder engine which with luck have managed to drain and I think without any damage. She's an oldish lady (1974) and it's never happened before. I'm toying with the idea of fitting an anti syphon-valve but I'm also questioning the state of the exhaust system and in particular the muffler. If I remove it, what should I be looking out for e.g. are there none return valves in there? should it be full of water? Any advice is very grateful.
Thanks

 

[VicS]

Hi, please can you help?
I have raw water in my Perkins 3 cylinder engine which with luck have managed to drain and I think without any damage. She's an oldish lady (1974) and it's never happened before. I'm toying with the idea of fitting an anti syphon-valve but I'm also questioning the state of the exhaust system and in particular the muffler. If I remove it, what should I be looking out for e.g. are there none return valves in there? should it be full of water? Any advice is very grateful.
Thanks

Mufflers vary. The Vetus ones are just a series of baffles inside.

The system ought to have a water trap to hold all the water left in the exhaust when the engine is shut down. Probably it will act as a good enough silencer for a separate muffler not to be needed.
If the water injection point into the exhaust is below or close to the water level. You should have an antisyphon loop and valve fitted

 

[scottie]

If you have a mcmurdo unit (looks like a rugby ball) they start as being a non return valve but eventually the slits stay open and produces this effect

 

[savageseadog]

Hi, please can you help?
I have raw water in my Perkins 3 cylinder engine which with luck have managed to drain and I think without any damage. She's an oldish lady (1974) and it's never happened before. I'm toying with the idea of fitting an anti syphon-valve but I'm also questioning the state of the exhaust system and in particular the muffler. If I remove it, what should I be looking out for e.g. are there none return valves in there? should it be full of water? Any advice is very grateful.
Thanks

I don't know anything about your engine or cooling system but would suggest you fit a new set of Vetus, water trap, muffler and goose neck to their guidelines if your're uncertain where to go on this.

 

[VicS]

I don't know anything about your engine or cooling system but would suggest you fit a new set of Vetus, water trap, muffler and goose neck to their guidelines if your're uncertain where to go on this.

To which end good advice /guidance can be found in the Vetus on line catalogue.

Esp look at the guidance on antisyphon loops and valves

 

[rlea]

Hi, please can you help?
I have raw water in my Perkins 3 cylinder engine which with luck have managed to drain and I think without any damage. She's an oldish lady (1974) and it's never happened before. I'm toying with the idea of fitting an anti syphon-valve but I'm also questioning the state of the exhaust system and in particular the muffler. If I remove it, what should I be looking out for e.g. are there none return valves in there? should it be full of water? Any advice is very grateful.
Thanks

It is a Vetus muffler and the water injection is below the waterline, so I guess the best is to go for the belt and braces approach - change the muffler and add an anti syphon valve?
Thanks for the advice

 

[VicS]

It is a Vetus muffler and the water injection is below the waterline, so I guess the best is to go for the belt and braces approach - change the muffler and add an anti syphon valve?
Thanks for the advice

I assume you mean change the muffler for a waterlock although if have a suitable and serviceable muffler it can be retained and the waterlock added at the lowest point
With a water injection point below the wter line you definitely need an antisyphon loop and air vent. Two types of air vent to choose from http://viewer.zmags.com/publication/04e44322#/04e44322/86

 

[rlea]

Thanks VicS

I assume you mean change the muffler for a waterlock although if have a suitable and serviceable muffler it can be retained and the waterlock added at the lowest point
With a water injection point below the wter line you definitely need an antisyphon loop and air vent. Two types of air vent to choose from http://viewer.zmags.com/publication/04e44322#/04e44322/86

Thanks VicS. Gave you a bum steer there, it's a waterlock and not a muffler which I'll e-mail Vetus and see what they suggest. I will fit anti syphon.

 

[VicS]

Thanks VicS. Gave you a bum steer there, it's a waterlock and not a muffler which I'll e-mail Vetus and see what they suggest. I will fit anti syphon.

If its a water lock then thats fine. You only need a muffler if additional silencing is required. In practice a good long run of rubber exhaust hose half full of water is not a bad silencer.

The water trap should be sized so that it is capable of holding all the water left in the system when the engine is stopped.

 

[rlea]

Again, thanks VicS. It's a vitus LP50 waterlock which has worked fine for years. I've e-mailed vetus and asked is it possible that it's failed, still waiting for a reply. I didn't drain it last winter, so may have damaged it? No leaks but I'm not sure about the inside? Is that possible or am barking up the wrong tree? Still intend to fit anti syphon valve.

 

[dratsea]

How is the water injected into the exhaust? I have an insulated manifold extension up to about the w/l and a 180Deg bend with water entering (outer chamber?) on the engine side but, I guess, injected on the exhaust side. Worked fine for years until one day I filled the engine with raw water. Luckily did not persevere with electric start and when it failed to turn by hand I feared I had bent a con rod but cleared out the water and she started. Cannot take it apart as they replaced the studs in (Al) heat exchanger with bolts through extension (so mild steel in aluminium alloy at exhaust temp and salt water) Now out of water and planning to remove heat exchanger with extension and give to proper engineer to take apart but guess bolts will sheer, drill out, weld, tap and put in new studs.

I think my problem is first that the inner membrane of injector has corroded so any water can fall down exhaust side and second that the end plate of raw water pump has worn enough to allow water to bypass it faster than the a/s valve can cope. Will let you know what I find and how it goes.

Regards,

Dratsea