Weird electrical issue

[burns3c]

Hello everyone, first post ever!

I have a Dickinson "Newport" diesel furnace on my 1983 Catalina 36 MK1. It does not use a gravity fed fuel system, it has a fuel line connected directly to the main racor. The old inline fuel pump recently failed, and I just installed a replacement (Universal Electric Fuel Pump 2.5-4PSI 12V HEP-02A Inline Low Pressure Gas Diesel | eBay). It works great, but it makes my cabin lights flicker, super annoying! Is there any way to resolve this? It seems like the way the little pump draws off the house bank.. its not a "steady stream" of DC voltage, but rather a kind of pulse. You can see the amp meter "vibrating" when the pump is on. I'm worried that this is just how this pump draws power, and that I basically just need to find a different pump, but I'm no expert when it comes to electrical and thought you pros out there might have some tricks. Thanks.

 

[FastOlson]

That's a very odd looking (and suspiciously inexpensive) little pump. I would check with the heater builder for ideas.

 

[Davidasailor26]

Welcome to the forum!

Where is the pump wired into the DC system? If it’s sharing wiring with the lights it could be that the load is causing a voltage drop on the supply wires, not really the power source. A little pump like that probably shouldn’t be drawing enough current to cause any voltage drop, but if it’s wired into the lighting circuit and those wires are just sized for small LED lights I guess it’s possible.

 

[burns3c]

They are both on the house bank, but separate circuits, which is why it's weird to me. Also the lights are not LED, if that matters.

 

[Benny17441]

Make sure the batteries are in good health. Test the pump's actual power draw against the specs of similar pumps. At that price point I would question if the design and manufacturing tolerances are the best for the application.

 

[jviss]

There could be a poor connection causing a significant drop with the pump load. I'd check grounds, and also the battery to load panel connections.

 

[jssailem]

Welcome to SBO @burns3c .
Congrats on the Catalina 36. Nice Boat.

Your Dickerson Newport Diesel Heater has certain demands for fuel. This means the pressure needs to be steady and at specified pressures. The manufacture specifies a Walbro pump. These are high grade pumps. They should be fused, switched directly to the battery.

Attached find the Fuel pages from the Heater Manual.

NOTE: The heater has an overflow return line requirement.
The manual also states that the fuel source should not be connected to the engine system (i.e. the Racor Filter for the engine supply). These are heater safety specifications.

 

[Tally Ho]

Says it draws 1-2 amps…pretty low draw.

how fast do the lights flicker..in sync with the pumping…?

The pump looks like the same kind that they use in the little diesel truck/bus heaters. Does it make A lot of noise (a common complaint of those cheap little pumps).


Greg

 

[burns3c]

Thank you, John, this is just the info I needed. I dont have a manual and was having trouble tracking one down. The cheap-o pump I put on there does seem to allow the heater to operate nominally (it puts out 3psi continuously), though I think running the motor and the heater at the same time might be an issue since it draws off the racor and doesn't have any sort of check valve installed. I will have to spring for one of these Walbro pumps at some point, as spendy as they are.

 

[burns3c]

Says it draws 1-2 amps…pretty low draw.

how fast do the lights flicker..in sync with the pumping…?

The pump looks like the same kind that they use in the little diesel truck/bus heaters. Does it make A lot of noise (a common complaint of those cheap little pumps).


Greg

Greg, the ampmeter shows its drawing just under 2 amps, which should be right, like you said. The flicker is exactly in sync with the pumping, yes. You can also see the needle on the ampmeter "vibrating" at the same rate. Noise wise, its pretty quiet, you really can't hear it unless you listen hard for it.

 

[jssailem]

Here is the website link I found the manual.
Diesel-Heater-Manual.pdf

 

[Michael Davis]

I’ve had two “Newports” and one “ Arctic”. My preference is to use a day tank if you can find a good space for it. They take 15/20 min. to fill with the little pump but then are good for a couple of days. This thread has got me thinking of a good place on our current boat. Another winter project!

 

[Davidasailor26]

I wonder if the 1-2 amps is an average, but the momentary load each time the coil starts drawing is much higher? If so a higher quality pump might be able to smooth the load better than leaving big spikes. Would be interesting to look at with an oscilloscope.

 

[burns3c]

I like the idea of the auxiliary tank. So maybe I can get a 2 gallon day tank, figure out a spot for it that makes sense gravity wise, then add an on/off valve between the racor and the pump. The cheap pump I have on there already should work fine for that, and I could find a decent aluminum or steel tank for way less than the cost of a new Walbro pump.

 

[FastOlson]

We recently installed a new forced air diesel furnace. I did not want the work/expense of installing a new outlet in boat's main diesel tank and running a fuel hose to the furnace pump, AND all these furnaces run cleaner/better on #1 Diesel (aka kerosene ) than the #2 diesel fuel we have available at fuel docks in the US.
This is the tank we chose. #2027: Fuel Tank 10 Liter (2.6 Gallon) - Wallas Marine and RV Heaters | Stoves | Cooking Equipment | ScanMarineUSA.com
We fuel it with kerosene from the hardware store.

Something to consider.......