Engine Driven Watermaker HP Pump

[Celestialsailor]

It's time for me to consider a HRO unit. Due to costs, I will probably make my own. After reading 1/2 a dozen how to articles, I can do it for under $2K and have a 20 gal@hr. unit.
The problem I see is the mounting of the HP pump. I could mount it on the diesel engine but a lot of rework for all the other driven items. I have a single pulley on my Westerbeke W46 and will machine a pulley to bolt onto it for the drive. So my question is...can I mount the HP pump on the engine beds? My belief is that the center of the crank, where I will be mounting the 2nd. piggy-back pulley, is very close to the centerline of the isolactic engine mounts. If the engine moves when loaded and revved up the crank pulley centerline should not be interrupted too much. Has anyone seen or have an HP pump mounted that way?
Hopefully Tellie chimes in on this.

[Tellie]

Originally Posted by Celestialsailor

It's time for me to consider a HRO unit. Due to costs, I will probably make my own. After reading 1/2 a dozen how to articles, I can do it for under $2K and have a 20 gal@hr. unit.
The problem I see is the mounting of the HP pump. I could mount it on the diesel engine but a lot of rework for all the other driven items. I have a single pulley on my Westerbeke W46 and will machine a pulley to bolt onto it for the drive. So my question is...can I mount the HP pump on the engine beds? My belief is that the center of the crank, where I will be mounting the 2nd. piggy-back pulley, is very close to the centerline of the isolactic engine mounts. If the engine moves when loaded and revved up the crank pulley centerline should not be interrupted too much. Has anyone seen or have an HP pump mounted that way?
Hopefully Tellie chimes in on this.

I'll be happy to chime in. But I have to state up front I am not a fan of engine driven high pressure pumps. I know it makes perfect sense up front and I don't knock anybody that wants to do it, but the major watermaker manufacturers all stay away from this design for good reasons. That being said, mounting the high pressure pump to your engine bed is a bad idea that will cause problems sooner than later. An engine driven pump needs to move with the motion of the engine and the only way to do that is to attach it to the engine. This can be a bit trickier than it seems at first and is usually the first place a DIY watermaker build gets into trouble and the 2k figure starts to rise. I would highly suggest that you contact Rich Boren. I know he has engine mounted pumps. There is a learning curve on making the brackets that mount to the engine. You'll want to mount the high pressure pump as close to the center of the engine as possible. These pumps are not light. The further it hangs out the more chance the normal engine vibration will be amplified. This can be only an extra inch or so that can make the difference between a nice smooth operating engine and one that that looks like it is going to jump out of the motor mounts. Again, talk to Rich I'm sure he already has a bracket that will work for your motor. What you might also want to do is post pictures of your design and let us take a look at it. I'm willing to bet we can help you not make some of the common mistakes that hurt that 2k line.

[Tellie]

A PS to the above.

I got a call from Sailorman two days ago to take a look at a Spectra NewPort 400 that came in. It was a mess and to get it back up to a real NewPort400 MPC3000 would be cost prohibitive for all involved. But the Clark pump looked in very good shape and it looks as though it's been re-maned recently. The membrane vessel is good and the important plumbing fittings are all there. But, for someone willing to build their own watermaker you could easily convert this unit to a 14gph manual unit. If you could get this unit as is from Sailorman around $400-$500 and put in about another $1,000 someone will have a very nice Spectra equivalent of a Cape Horn Extreme 330gpd unit which for all intents and purposes is thee most energy efficient watermaker made, even in Spectras line.
I have no affiliation with Sailorman and though I would be willing to lend advice on how to convert this system to anyone who bought it I get no compensation from Sailorman.

[Celestialsailor]

Originally Posted by Tellie

A PS to the above.

I got a call from Sailorman two days ago to take a look at a Spectra NewPort 400 that came in. It was a mess and to get it back up to a real NewPort400 MPC3000 would be cost prohibitive for all involved. But the Clark pump looked in very good shape and it looks as though it's been re-maned recently. The membrane vessel is good and the important plumbing fittings are all there. But, for someone willing to build their own watermaker you could easily convert this unit to a 14gph manual unit. If you could get this unit as is from Sailorman around $400-$500 and put in about another $1,000 someone will have a very nice Spectra equivalent of a Cape Horn Extreme 330gpd unit which for all intents and purposes is thee most energy efficient watermaker made, even in Spectras line.
I have no affiliation with Sailorman and though I would be willing to lend advice on how to convert this system to anyone who bought it I get no compensation from Sailorman.

so I take it that it was the electronic board that automates the back washing and re-pickling and such. My first choice was to have a 12v unit and up my charging capacity to make up for the power to the HRO.
That Spectra sounds like the ticket. I would appreciate a PM from you with Sailormans contact info. Thanx for the lead

[Celestialsailor]

Originally Posted by Tellie

I'll be happy to chime in. But I have to state up front I am not a fan of engine driven high pressure pumps. I know it makes perfect sense up front and I don't knock anybody that wants to do it, but the major watermaker manufacturers all stay away from this design for good reasons. That being said, mounting the high pressure pump to your engine bed is a bad idea that will cause problems sooner than later. An engine driven pump needs to move with the motion of the engine and the only way to do that is to attach it to the engine. This can be a bit trickier than it seems at first and is usually the first place a DIY watermaker build gets into trouble and the 2k figure starts to rise. I would highly suggest that you contact Rich Boren. I know he has engine mounted pumps. There is a learning curve on making the brackets that mount to the engine. You'll want to mount the high pressure pump as close to the center of the engine as possible. These pumps are not light. The further it hangs out the more chance the normal engine vibration will be amplified. This can be only an extra inch or so that can make the difference between a nice smooth operating engine and one that that looks like it is going to jump out of the motor mounts. Again, talk to Rich I'm sure he already has a bracket that will work for your motor. What you might also want to do is post pictures of your design and let us take a look at it. I'm willing to bet we can help you not make some of the common mistakes that hurt that 2k line.

One design I had was the HPP mounted directly on the front drive pulley via an electrical clutch. The other design was a light hydraulic pump off the engine, connected to a hydraulic motor, to a HPP in a remote area. Both designs work best when my boat is less than 1 hour from my Machine Shop. But...I'm in Mx. So the Spectra looks like a great option.

[phorvati]

I have a single 1/2" V belt driving a Cat 290 mounted directly below W40 4-108 front pulley. I mounted it on the stringers and so far its been 2 years with the same belt. But vibrations are there. Prior to westerbeake I had the same setup with Atomic 4 driving the same pump for about 2 years as well on the same belt.
I use this setup 6 months per year and make water 2 hours per week. But i only run it at anchor or with engine in neutral, and after every run i flush with product, and take the belt off. At higher RPMS I have no vibrations what so ever cause my engine is aligned very well. I do have considerable engine rocking at 800RPM which is about the speed that gives me good brine flow. At higher RPMs 950-1000RPMs, pulsations become too much. Or perhaps the feed pump cant keep up with brine flow demand.
The setup has worked for me but I am getting sick of setting up the belt every week. I'll probably be looking at fabricating something. I've also been eyeing a CAT pump Clutch but i am not ready to drop 200+ for that or pulsation dampener just yet.
It is a pain in my a.. to put the belt on every time you make water, but it worked good for the past 4 years. Also that Cat 290 is sweet, parts are plentiful and cheap, yes its not stainless, but it cost me only 90$ on ebay and i had to spend another 70$ or so on the service kit(s). I flush it after every use, and it held up quite nicely.

And as far as that 2k figure that Tellie mentioned, I am way over that, more like double, but I commissioned my home made WM in 2006, and learned from costly mistakes along the way. I like that i can fix anything that breaks almost immediately, and i have spares.

[Cotemar]

you can get a Cruise RO 20 GPH watermaker all made for $4200 and just run it off your generator.

WaterMakers

[Cotemar]

Here is some good DYI Watermaker info

[SV THIRD DAY]

Engine driven installations are always the hardest to pull off properly, but knowing you are in La Paz with Sergio the Welder, it could be done....but the real question is do you really want to do it? I am now up to 4 cruisers returning the Engine driven clutch/pump after trying to make it fit on their enginee and swapping out to the 1.0Hp motor approach powered by their Honda or diesel genset. Doing it right isn't easy. But there is a great installation on the boat Milagro, a Catalina 42, in Marina de La Paz and Michael would have no problem letting you come over and take a look at it.

Go talk to Tom on SV Eagle at La Paz Cruisers Supply in Marina Palmira, he has one of our engine driven and motor driven water makers in his store there in La Paz and you can tough and feel it and imagine how in the world to mount it in your boat.

I have had both engine driven, Kubota driven, and a 1.0 HP driven water maker and the easiest to deal with without a doubt is the simplicity of the 1HP ac motor.

[SV THIRD DAY]

For the poster talking about pulsations above a specific RPM, that is the classic cavitation symptom caused by your boost pump not keeping a positive supply of sea water going to the HP pump. Pulsations like that are not just hard on your HHP pump but can cause death to your RO Membrans. If you ccan't upgrade your boost pump, then you are right to limit your engine RPM to keep down the flow rate of your HP Pump.

[Celestialsailor]

Originally Posted by SV THIRD DAY

Engine driven installations are always the hardest to pull off properly, but knowing you are in La Paz with Sergio the Welder, it could be done....but the real question is do you really want to do it? I am now up to 4 cruisers returning the Engine driven clutch/pump after trying to make it fit on their enginee and swapping out to the 1.0Hp motor approach powered by their Honda or diesel genset. Doing it right isn't easy. But there is a great installation on the boat Milagro, a Catalina 42, in Marina de La Paz and Michael would have no problem letting you come over and take a look at it.

Go talk to Tom on SV Eagle at La Paz Cruisers Supply in Marina Palmira, he has one of our engine driven and motor driven water makers in his store there in La Paz and you can tough and feel it and imagine how in the world to mount it in your boat.

I have had both engine driven, Kubota driven, and a 1.0 HP driven water maker and the easiest to deal with without a doubt is the simplicity of the 1HP ac motor.

Actually I talked to Sergio about another TIG job on my boat and found he is charging as much as in the US. Being a Toolmaker/Machinist, I thought I might find a way. I'm still looking into it but may find a 12 volt unit. It has never made sense to me to generate 110VAC to drive an AC motor, to drive a HPP. If I had a diesel gen set, then I could see it. But to have something like a Honda generator ($1100) and then a watermaker and the introduction of active gas while cruising does not appeal to me.
I should just state here my HRO needs. I carry 115 gallons onboard. Here to the Marquesas is around 30 days (safely). If I had the ability to make 4 gallons, every other day, that would be perfect. I'm beginning to see used 12volt units here and other resources that are pretty cheap. Maybe you know of a few.

[colemj]

Help me with your math. If you have 115gal, and use 4gal every other day (2gal/day) and need sufficiency for 30days, won't you be arriving with 55gal still in the tank with no watermaker at all?

Mark

[Celestialsailor]

Originally Posted by colemj

Help me with your math. If you have 115gal, and use 4gal every other day (2gal/day) and need sufficiency for 30days, won't you be arriving with 55gal still in the tank with no watermaker at all?

Mark

Let me help you with your comprehension...I said " If I had the ability to make 4 gallons, every other day". So over 30 days, I would make an extra 60 gallons, giving me a total of 175 gallons. This would give each person almost 3 gallons a day. Which to me is comfortable.

[colemj]

Thanks, I get it now!

Mark

[Cheechako]

I've done a few engine drive units and they work great. One was a 1.5 hp 120 volt unit that I converted to engine drive. I fabricated a bracket for the Cat pump and bought the Electric clutch.
Although It goes against proper installation thinking, I have seen refrigeration drive pumps mounted on the hull next to the engine with no issues. Long belt with an idler on the belt.
The engine drive watermakers make a lot of water fast and the biggest issue is using the water up so you can run your watermaker often!