Plumbing For Volvo Penta

[Katoh]

Hi All
In the process of removing an ad31b from my boat to do a few repairs, A mechanic friend told me what to replace before putting the motor back and one was all the raw water and cooling hoses, Iv been searching on the net and other means and to buy original Volvo Penta hoses is extremely expensive.
Does anyone make an aftermarket hose, or can you use some other hose PVC or whatever with metal bends. Any ideas?
The boat is plate Alloy, I don't know if electrolysis comes into the equation, but I remember reading that you should not use carbon rubber?
Thanks
Katoh

[kenJ]

I am not familiar with the engine. Unless there are sections that are engine specific any good quality hose will work. Suction side of the pump or sections with large bends should be wire reinforced. May want to visit your local auto parts store.

[CDK]

Hose and fan belt makers like Gates have a range of "universal hoses" with harmonica walls that you might use instead of the expensive Volvo ones.
Straight hoses with metal knees are another option, but not a cheap one. I marinized two VW diesels and spent a substantial sum on copper knees and stainless hose clamps. The hardest are hoses with different end diameters, for which you have to make metal adapters.

[gonzo]

You can use any rubber hose with fabric reinforcement. Some factory hoses have different diameters at each end, so you need a reducer.

[Katoh]

Gentlemen
Thanks for the replies, great news that I can use aftermarket. going to save big $ were I can put that into better areas of the vessel.
Cheers
Katoh

[Katoh]

Surfing the net tonight I came across these
http://www.summitracing.com/parts/SUM-390124/
Looks very interesting and would last a lifetime (maybe)?
Still cheaper than Volvo parts, What do you think?
Katoh

[CDK]

You can save a lot of $$ if you use these:
http://pitstopusa.com/c-135191-cooli...ator-hose.html

I tried a stainless one on a single cylinder diesel generator, it lasted less than 20 engine hours.

[Katoh]

CDK, You are spot on! I wrote to the manufacturer and they just came back to me with the same thing, definitely not marine grade. Those hose's in the link are good but too short, maybe I could put a piece of stainless pipe in the middle and use 2 smaller pieces.
I am sure I read somewhere regarding the composition of raw water pipes in stern-drives had to be of a certain material, Any carbon rubber pipe would add to electrolysis and the motor would be the looser. Another thing that I came across was these http://www.unicoil.com.au/
but again it depends if they can handle the salt water environment?
Katoh
Had another quick thought, could I not be able to use the original pipes as a template, and bend some stainless pipes up in the same shape, then use a straight hose to fit fit either side?

[CDK]

Katoh, do not worry about the carbon in rubber hoses. The electrical conductivity is very low and does not contribute to corrosion.

Two rubber hoses with a piece of stainless pipe is a good solution.

[Katoh]

CDK, That's excellent I'm getting happier with every post, This might be a no no but can I use copper pipe or only stainless? Remember its an aluminum hull.
Many Thanks
Katoh

[CDK]

Of course you can use copper as long as it isn't in direct contact with any other metal part.

[michael pierzga]

Metal plumbing...specifically Stainless steel should not be used. Stainless steel corrodes when deprived of oxygen... wet. Stainless steel is only used for plumbing components that live in a wet, dry environment.

Metal plumbing its difficult to use...to Bend, to add pipe barbs or fittings and generally produces a messy dissimilar metal instalation .

Best to visit your local plumbing shop and see what kind of PPR systems they stock and fabricate. .

PPR is not PVC. PPR is heat welded pipe, not glued.

Isolate solid plumbing from vibration with rubber flex lnks.

http://www.aquatherm-pipesystems.com/67.0.html?&L=2

http://dexterton.com/prodbrand_view....=226&cat_id=12

http://www.piping.georgfischer.com/g...ucts?real_id=2

[Katoh]

The PP-R piping looks very good indeed, now welcome to my world down in Aus, Just doing a quick search for suppliers or materials yielded not a great deal, and nothing of worth while. The other problem is cost, being new will cost a fortune down here, to get it imported the freight will get you, its a viscous circle, So far copper tubing is wining hands down, can buy preformed bends and easy to work even bend. and nowhere near the price of volvo hoses, maybe even outlast the motor? A friend told me me what you really want is brass piping. I don't know enough to comment one way or another.
I will ask at our major plumbing supplier outlet next week about PPR, being a builder I have some contacts under my arm, but I'm not real confident anything will originate, it will be an interesting exercise. Ill post the outcome for future reference.
Many Thanks
Katoh

[michael pierzga]

I dont know your market , but I do know that Australia is a sophisticated place.

PP plumbing is available from my local plumbing shop. The complication with PP is that the joints are heat welded. For me this is no complication because the local residential, industrial, plumbing shop has the dies and electric heat welder to fabricate the joint.


On the boat I simply cut PPR to length, then fit dry assembled the piece of plumbing, with MAGIC Marker tick marks on the tube fittings joints to identify joint angles , then bring to the plumbing shop to have them heat weld the assembly.

Not expensive... and since I have the option of hundreds of different standard plumbing fittings in PP...nipples , unions, reducers..... its fast and cheap. Also PP is easier to hand bend, on site, to complicated forms , with a hand held heat gun.

Remember that PP plumbing comes under a range of technical use specificatios.....Im not aware of all the specs..ask you plumbing pro for advice

I suggest that when plumbing a boat , you ask your local..INDUSTRIAL... professional plumbing shop for advice on cost effective solutions.

Metal plumbing is complex, prone to galvanic corrosion and is not cost effective.

As to the original poster, many standard silicon rubber hose components are available from commercial supplies like auto repair shops.

Volvo may have unit specific hoses, but Many hose fittings are the correct dimensions for marine engines. Seek the auto part catalogue for cost effective solutions.

[CDK]

Originally Posted by michael pierzga

Metal plumbing...specifically Stainless steel should not be used. Stainless steel corrodes when deprived of oxygen... wet. Stainless steel is only used for plumbing components that live in a wet, dry environment.

The usual nonsense Mchael!

From the 1th lines of Wikipedia (your favorite source) on corrosion:

Corrosion...... In the most common use of the word, this means electrochemical oxidation of metals in reaction with an oxidant such as oxygen.

Stainless (V2A) is the number #1 plumbing material in the food industry: no corrosion and suitable for temperatures exceeding those of plastics by a factor 10.
Yanmar uses stainless for the critical parts in their cooling system.