Diesel Fuel Polishing

[s/v Jedi]

Originally Posted by Cheechako

On a really mucky system I suppose you need a prefilter before the pump. (?) Normally, a filter is after the pump. Most all the hydraulic systems I've been exposed to insist the filter is after the pump. Most pumps push better than they pull, as the filter flow rate decreases, the pump can still push the fuel through. Imagine putting a pump after your Reverse Osmosis watermaker membranes..

Yes, there are many systems where a filter is located after the pump, but not in this case, or so many others. Your fresh water pumps have filters before the pumps, as have your raw water pumps on engines, gensets etc. It is very common to have a filter at the suction side of the pump. Your watermaker has filters at the suction side of the pump too, it's just the membrane that is located after the pump.

In the case of using Racor filters, there is no question as they are designed to operate in vacuum mode, i.e. on the suction side of the pump. If you connect it the other way, you connect it wrong according to the manufacturer.

ciao!
Nick.

[clayzone]

Just now saw this threat. This guy has a easy, cheap setup. What is different about his is the way he eliminates the grud. How to clean diesel fuel tanks in boats

[DeepFrz]

Yes we have seen that one before. It is one way to do it on a budget. A higher volume pump would probably cut down the time needed and might help loosen some of the crud attached to the bottom and sides of the tank. That's just MHO.

[Bambolera]

I'm currently putting my fuel polishing system together and want to add a vacuum gauge between the filter and the pump. Raycor wants over $100 for their gauge that replaces the T-handle on their filters. Is there something special about their vacuum gauge?

I found this one, and many others, for a fraction of the price.

Winters PEM Series Steel Dual Scale Economy Pressure Gauge, 30"Hg Vacuum/kpa, 1-1/2" Dial Display, +/-3-2-3% Accuracy, 1/8" NPT Bottom Mount: Amazon.com: Industrial & Scientific

[s/v Jedi]

Originally Posted by Bambolera

I'm currently putting my fuel polishing system together and want to add a vacuum gauge between the filter and the pump. Raycor wants over $100 for their gauge that replaces the T-handle on their filters. Is there something special about their vacuum gauge?

I found this one, and many others, for a fraction of the price.

Winters PEM Series Steel Dual Scale Economy Pressure Gauge, 30"Hg Vacuum/kpa, 1-1/2" Dial Display, +/-3-2-3% Accuracy, 1/8" NPT Bottom Mount: Amazon.com: Industrial & Scientific

Yes, the difference is in quality. What they call "economy", you should read as "cheap junk"

[delmarrey]

If you want quality gauges, go here>>> http://www.valworx.com/category/s?keyword=vacuum+gauges

[DeepFrz]

You definitely want one with a tell tale needle.

[Bambolera]

Originally Posted by delmarrey

If you want quality gauges, go here>>> Valworx: Actuated Valves & Controls - Ball Valve, Butterfly Valve, Solenoid Valve

Thanks for the link.

I'm not sure that my application is industrial; it certainly isn't "demanding;" but it's nice to know I'm not buying "junk."

Industrial Vacuum Gauge 2, 30 Hg | Industrial Gauges 2 Lower Mount | Valworx ®

Looks like this one should serve my purpose for a fraction of the Raycor price. I hope I'm not missing something.

[markpierce]

Go dual. When a filter clogs, you can quickly/easily switch to another.

[Seaworthy Lass]

Originally Posted by markpierce

Go dual. When a filter clogs, you can quickly/easily switch to another.

This does not always help much unless you have an unlimited supply of filters on board. If fuel is badly contaminated even a new filter can completely clog within half an hour.

[delmarrey]

One thing that should be noted;
Some fuel pumps like Yanmar 3JH, they are only rated at 2.9 psi, so if a filter is clogged the gauge would have to cover very small amounts of vacuum.

So on some motor/filters a vac gauge wouldn't work . But on a scrubbing system where the fuel is forced thru a filter and back into the tank with a impeller type pump a pressure gauge would work fine.

On the diesel fuel trucks I maintained, the gauges were differential gauges, which read the difference between the input and output lines. These give you a true reference of the filters condition. One documents the difference of a brand new filter and watch it climb up to about 15 psi as it gets older/used, then it's time for a change. Like this one>>> Differential Pressure Gauge 2.5 | Valworx ® But these are not cheap!

[Bambolera]

For choosing a suitable fuel pump, I found this helpful:

Marine Fuel Polishing Systems Using Walbro Fuel Pumps from Fuel-Pumps.net

[goboatingnow]

Originally Posted by Bambolera

For choosing a suitable fuel pump, I found this helpful:

Marine Fuel Polishing Systems Using Walbro Fuel Pumps from Fuel-Pumps.net

For diesel any Jabsco 12v impellor pump, once the rubber bits are nitrile , will handle diesel fine, I've been using one for 10 years as a transfer pump.

Dave

[s/v Jedi]

Originally Posted by goboatingnow

For diesel any Jabsco 12v impellor pump, once the rubber bits are nitrile , will handle diesel fine, I've been using one for 10 years as a transfer pump.

Dave

Yes and you can get those reversible too!

But never let them pump towards an engine as their output pressure is too high, so you can't use it for bleeding or as boost pump.

[Bambolera]

Originally Posted by goboatingnow

For diesel any Jabsco 12v impellor pump, once the rubber bits are nitrile , will handle diesel fine, I've been using one for 10 years as a transfer pump.

Dave

I have a Jabsco that I use for changing the motor oil. It works great for that purpose. I'm sure it would also work for transferring fuel, but I wouldn't want the noise and amperage draw for an extended period.

The Walbro FRC-6 was almost $200 after shipping; but, after giving it some thought, it's money well spent and the right choice for me.