chris-s
Well-known member
Can anyone point me in the direction of a replacement for one of these? Fitted to a late-eighties Beneteau with a Volvo engine (if that helps any)
Chris
Chris
Find me this engine anti-siphon
- Thread starter chris-s
- Start date
Bobc
Well-known member
Why? Just buy a modern plastic one.
VicS
Well-known member
I guess it's a Volvo one but I don't think I've seen one like it.
Where does the hose top left go to.?
What engine is it for?
Can you not service the existing one?
Sandy
Well-known member
What is it and what does it do? Looking at the photo I am scratching my head in wonderment.
chris-s
Well-known member
The ‘extra’ hose top-left feeds to the stern tube. That’s what most of the commonly available plastic ones don’t have.
Leighb
Well-known member
It is/was a Volvo part. There was one fitted to our Halmatic 30. There were two versions, one like yours with a hose leading away to “piddle” the small amount of water out to act as a tell-tale. The other type had a valve in the top arm which admitted air when the engine stopped to avoid a siphon. These tended to stick and or block defeating the whole purpose. Ours was replaced when we re-engined.
Jokani
Active member
Here is a link - Search | ASAP Supplies - I have the Maestrini metal version installed, it is a quality bit of kit IMHO.
I do not use a valve, just a pass-through pee system.
I do not use a valve, just a pass-through pee system.
dankilb
Well-known member
I just made/assembled a version myself from the sort of DZR hose fittings (Maestrini) available from ASAP supplies. Female 3-way equal tees are available in various diameters. You can then add male hose tails to suit (ours have a 45 degree bend and are 25mm for the main flow - the piddle is a straight 10mm tail). I was going to feed the shaft seal from an extra 10mm tee beyond the piddle - similar to the OP's pic - but decided for a low-revving cruising yacht I wouldn't bother (it's a lip seal). The total cost was quite a bit less than the equivalent purpose-built DZR siphon loop fitting and allows for various options/setups.
Bilgediver
Well-known member
Piped up in that manner it is no longer an antisyphon device . The small top connection should be to atmosphere in order to stop the symphonic effect. Here it may be able to Syphon back into the engine unless the upper black hose ends in air .
chris-s
Well-known member
…which it does.
wingcommander
Active member
The piddle pipe becomes the siphon break ,once the engine has stopped this drains with gravity , then allows air in to break the siphon.
scottie
Well-known member
Repair kits were available ie copper washer and diaphragm which had tiny hole
You removed the valve assembly and replaced it whilst upside down dropping the diaphragm int the reces in cap
I suspect that the additional hose fitting is a modification
You removed the valve assembly and replaced it whilst upside down dropping the diaphragm int the reces in cap
I suspect that the additional hose fitting is a modification
Pye_End
Well-known member
Looks like Halyard Marine, though not sure about the extra pipe.
VicS
Well-known member
The same type does not seem to be available any more. You have a choice between fitting one of the types currently available (eg from ASAP Supplies) and a tee off to the stern gland or to refurbish the original. Consider removing the internal diaphragm and feeding the constant stream which will flow overbord or in to a cockpit drain where it can be seen. It is unlikely to block and will act as a telltale to show that the pump is functioning..
[194224]
...
The OP is not alone in wondering about this. In this link from a French forum the owner of a 1989 Beneteau is asking the same question but without any luck. One respondent reckoning that the mysterious fourth connection (top left) has been added later which does not seem likely given there are now at least two examples. Vetus seem to have made one that looks remarkably similar except for the extra limb. Anti-Siphon
dankilb
Well-known member
It is just a three- (or four-) way tee, whatever way you look at it. I’m not sure where the uncertainty arises in terms of replacement options - cheap plastic version, expensive Maestrini version, or make up your own from DZR pipe fittings.
Caladh
Well-known member
Yup replaced mine with a Vetus air vent rather than original water type.
Bilgediver
Well-known member
That is good. It appeared to be diving down to wash out the shaft seal . The kink at the fitting doesn't help.
Mistroma
Well-known member
The OP said:
I think that was probably read as it feeding the stern tube rather than just being a piddle tube where water can be seen exiting the end.
I wonder if the OP has a type of "Volvo seal" at the stern tube, like the Orbitrade version with a vent pipe. The vent pipe allows air to escape and removes the need for burping. I'm puzzled about the mode of operation and see 2 options if it is a Volvo seal.
1) Anti-syphon device doesn't have a valve at the small pipe's connection and some water always feeds the stern tube rather than a Volvo seal. I had a boat with pressure lubricated Cutless bearing, though it fed in at the bearing rather than the void in front. I can't see that working as a syphon break as the end is always under water.
2) Anti-syphon device does have a valve at the small pipe's connection and no water comes out when the engine is running. It would allow air to escape from a vented style Volvo seal. However, the Volvo seal just fills with water after initial venting. I can't see that working as a syphon break either.
It would help if OP could confirm that the hose does feed the stern tube with a constant supply of water or if that was an assumption. Details of the connection point would also help. e.g. To Volvo seal, Cutless bearing, stern tube, etc. This would help to decide if a standard plastic ant-syphon device would work or if it is something more unusual.
It doesn't look as if it has a non-return valve and just piddles out water from the restricted outlet when the engine is running. That's just a guess and I'm dubious about how well it works as a syphon break. I assume the actual vent pipe is the larger one at the top and that breaks the syphon but don't think OP confirmed that fact.
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Tranona
Well-known member
When a water feed goes to a Volvo seal it is injected into the end of the stern tube aft of the seal. Very common on Beneteaus, although in their case with small engines it is drawn from a scoop underwater. Many other seals such as the PSS and Tides have water injection although not always necessary on low speed, low power installations. The Radice version of the Volvo seal has a vent tube that can also take a water feed. This would normally be a bleed from the engine raw water, which is what this one has. Often this is just a simple T into the raw water pipe, but in this case the take off is incorporated in the antisyphon. Important that it is above the waterline and before the syphon break.
If the OP is not able to get a direct replacement or clean/re-use the existing then he will have to re-plumb. More details of the complete system would be helpful to advise alternatives
This betamarine.co.uk/resources/Operators_Manuals/10-115T-HE-OM/#page=31 a typical layout. The OP's one piece valve is essentially the same arrangement as in figure 25
If the OP is not able to get a direct replacement or clean/re-use the existing then he will have to re-plumb. More details of the complete system would be helpful to advise alternatives
This betamarine.co.uk/resources/Operators_Manuals/10-115T-HE-OM/#page=31 a typical layout. The OP's one piece valve is essentially the same arrangement as in figure 25