Oil Burner Pump FAQs 2

Fix the oil burner pump - fuel unit
Air bleeding
Air leaks
Filter Screen
Flooding oil buner
Foam in the oil
Oil Line Clogs
1-line vs 2-line Oil Piping
Pressure Setting & Tests
Replacement
Rotation Speed
Vacuum Testing for Leaks

Oil Burner Fuel Unit Strainer Screen FAQs

Tip: see OIL BURNER FUEL UNIT ANNUAL MAINTENANCE, SERVICE & REPAIR PROCEDURES - including removal of the fuel unit end cap to clean or better, repalce the internal filter screen at annual maintenance.  

And see OIL BURNER FUEL UNIT MANUALS & MAINTENANCE GUIDES - PDF downloads 

Thorough service of an oil burner fuel unit includes opening up the fuel unit side by removing the 4 bolts to reveal a replaceable filter screen that should be changed at annual service.

Do Beckett oil burner pumps have strainers in them ?

Do Becket oil burner pumps have strainers in them ? On 2017-10-21 by Charles kalemjian

by (mod) - Yes - and the strainer needs regular replacement

Charles,

Yes.

All of the current Beckett oil burner manuals, in discussing the oil burner fuel unit maintenance, include a cloudy statement

"Remove and replace the fuel unit strainer if applicable"

- which I take to mean IF you have disassembled and cleaned the fuel unit you should replace the strainer - something I was taught to do always at every service job, although I realize that overworked service techs often omit this step.

I have not found a fuel unit (oil burner pump) by Beckett, Carlin, or Webster or Sunstrand that did not include a strainer.

My photo shows the strainer in a Beckett Cleancut A2EA-6528 fuel unit (oil burner pump).

Watch out: when installing a new strainer in a fuel unit be sure the strainer is properly seated and that the four cap bolts are properly torqued.

An air leak at this location can lead to loss of heat or even unsafe oil burner operation.

After replacing the filter screen in the fuel unit the pump is now bound up and won't turn on only makes buzzing sound

While replacing filter inside pump, is now bound up and won't turn on only makes buzzing sound On 2019-02-18 by Jon

Reply by (mod) -

That doesn't sound good and I'm not sure what's wrong. If the pump was working perfectly well before you change the filter screen I wonder if perhaps a piece of debris that's gotten into the moving parts inside the pump during that change up process.

Check the coupling between the fuel unit and the drive motor. Then remove the pump from the oil burner and confirm whether or not the shaft is frozen.

Air Leaks Foaming in Oil at the Fuel Unit FAQs

Oil burner fuel unit air leaks in or oil leaks out

My Suntec fuel unit isn't sending oil through the high pressure line from the pump outlet to the oil burner nozzle assembly.

I disassembled the fuel pump and the screen was clean. When bleeding the unit, there were a lot of small air bubbles (foam-like), even after two minutes of purging.

This eventually gave way to a strong stream of oil, but still nothing coming from the high pressure line. Does this sound like a bad pump or is there a blockage of some kind?

The heating system has a Beckett burner and the whole system is about six years old.

Thank you in advance for any help you can offer. On 2017-12-29 by Doug

Photo: a Beckett fuel unit disassembled by the author, so as to show more of its internal parts.

by (mod) -

Doug

It's normal to get lots of air out of oil piping right after changing an oil filter or disassembling the fuel unit. I'm assuming you got this at the air bleeder valve attached to a tube dumping foamy oil into a container.

When the oil runs clear with absolutely no air bubbles it should have been successfully purged.

Of course a small leak can be subtle and recurrent and hard to find. But I'd not expect that to produce zero oil output at the high pressure port.

If no oil exits the high pressure line, and assuming you haven't fouled up the pressure adjustment on the fuel unit, then it sounds as if a valve in the pump is not operating. Don't keep running it as you could blow as seal and splash oil all over creation.

by Doug - Is this time to replace the fuel unit or is this something I could 'free up' in some way?

Thank you for your quick reply.

If it is a nonoperational value in the pump, is this time to replace the fuel unit or is this something I could 'free up' in some way?

The unit sometimes produced a short, shrill sound and one second burst of oil, but only once every third of fourth attempt (thank you for mentioning the fact that I could blow a seal, so I won't keep attempting this).

by (mod) -

Doug,

With the apology that I am obligated to point out that I can't be confident of a detail of diagnosis overheating system fuel unit based on a brief a text,

I will add that although it might be possible to disassemble and clean and repair a fuel unit with a stuck check valve, or some other internal problem, those are not things that any heating service tech would attempt in the field.

It's just more cost-efficient to swap in a new unit.

As we have warned elsewhere in these faqs,

Watch out: we do not reommend that you try disassembling a fuel unit unless you are trained to do so. Making a mistake could result in a leak, loss of heat, or worse, a building fire, injuries, or worse.

Sunstrand J Pump Replacement

How do I find the right replacement oil Pump for an old Miller oil gun furnace?

I have an old Miller gun oil furnace. It has a oil pump SunStrand J2CBF, CR1. I need to replace the pump, but I don't know where to find one. Do you suggest a replacement?
- On 2017-11-01 by Joe Coate - H

by (mod) - Sunstrand J pumps are still avaliable

Joe,

It has been quite a while since I have installed one of the older Sunstrand J-pump fuel units, but the last time I was up heating supplier replacement models were still available.

I need to be sure to get the correct pump for the correct rotation direction and be sure that the new pump is set up correctly for 1-line vs 2-line oil pumps depending on how your original oil burner was working.

1-Line vs 2-Line Fuel Units / Oil Pumps

How do I change a 2-line to a 1-line oil pump?

How do you convert a 2 line pump to a 1 line pump On 2017-02-24 by Eddie

Reply by (mod) - steps in converting from 2-line to 1-line heating oil delivery

Standard factory-set-up for an oil burner or oil burner pump usually delivers a fuel unit with an "internal bypass" in the fuel unit "open".

That's the set-up for a one-pipe oil piping hook-up. The open internal bypass means that excess oil beyond what can be delivered to the oil burner nozzle will bypass the pump outlet and recirculate in the unit.

When we change from a 1-line to 2-line setup we have to close that bypass port.

Details of how that is done are at

• INTERNAL FUEL UNIT BYPASS CONTROL

So in for some reason you have a fuel unit that was previously used on a 2-line oil delivery system for an oil burner and you need to change it to a 1-line set-up you have several things to do:

• Open the internal bypass plug in the fuel unit
• Remove the return lin connected to the fuel unit
• Close the return line connection port with a properly-sized pipe plug

Really? Just to be sure we're on the right page here, if you were asking about water pumps, not oil pumps on an oil burner, for those jet pumps that are convertible, usually the pump's front-end of its impeller assembly is removed and a one-line jet pump front end is bolted on.

See WATER PUMP, TWO LINE JET

Why can't I get my new 2-line oil pump working?

I put new pump and and new oil lines.

It's a two line pump set-up, but I still cant get it to actually pump fuel.

I checked the round gear behind pump its fine. On 2016-10-28 by sam

Reply by (mod) -

Check the internal bypass plug in the pump = your pump may be set-up for a one-line piping system with the internal bypass open when it needs to be closed.

Watch out: making a mistake between 1 and 2 line pump setups can cause such high oil pressure that you may blow the fuel pump and cause a building fire.

Oil Flooding the Combustion Chamber - is it the fuel unit? FAQ

What is causing my furnace to flood the firebox with heating oil?

what would cause my furnace to flood the firebox with fuel? it was working normally, i shut it off and left for the weekend. when i returned , i noticed fuel oil on the floor of the shop. have fuel shut off at the tank until i can look into it further, but not sure where to start. any help? Beckett pump. On 2016-10-25 by mojo

Reply by (mod) - Causes & Cures for Oil Burner Combustion Chamber Flooding

Basically a fuel flooded combustion chamber happens because the oil isn't being burned, possibly also because excess heating oil is entering the "firebox" due to an oil line or nozzle or nozzle adapter leak.

Watch out: A fuel-flooded oil burner fire box is more than nasty it's downright dangerous as a subesequent effort to re-start the burner can result in a PUFFBACK EXPLOSION (search InspectApedia for that term using the search box just above).

Depending on the age of your system and just what safety controls are installed, one of several types of flame sensors such as a cad cell relay or a stack relay is intended to shut down the oil burner motor and thus the fuel unit pump if no flame is established after 20-30 seconds, thus protecting against oil flooding.

Several things can happen to mess this up:

1. The safety device may not be working - it doesn't shut off the oil burner motor

2. A homeowner might keep pressing the re-set button repeatedly, causing flooding of the combustion chamber

3. The controls might be working but a defective automagic shutoff valve within the fuel unit could be stuck open (typically from dirt on the valve seat inside the fuel unit).

That situation combined with an oil storage tank that's above ground and full enough to send oil to the oil burner by simple gravity could also flood the system.

You should

1. SHUT OFF the oil burner and leave it off IMMEDIATELY

2. SHUT OFF the oil fuel line into the burner - there should be a fusible-link oil line valve right at the oil burner or if not, on the oil line near the burner or at the oil tank

3. Call your heating company for repair. Be sure to tell the tech that the combustion chamber is flooded.

Fuel Unit Fails When Hot FAQs

Oil Burner fuel unit fails when the burner has been on for a time?

So I have the intermittent flame problem as well, only thing with mine being different is the burner fires of perfectly every time for about 15 minutes great flame couldn't be adjusted any better.

Cad cell is nice and snug and I roughed up the contacts on the back side of the contacts to make sure great connection.

I have blown out oil tank plus lines to rule out debris, new tip, contacts are all realigned, new oil filter was also put on, new relay box put on, new thermostat.

The oil pump and electric drive motor sound no different on the burner,

Now I have an old Aero burner in my basement from an old furnace which I know the pump on it works great now the rpm speeds are the same at 1725 rpm can I just switch the two out?

Regardless of brands, mounting holes seem to be the exact same size. On 2016-10-09 by Christopher

by (mod) - possible causes of intermittent oil burner failure that happens after the burner has been on for a time: note that your failure occurs after the burner has been running.

Thanks for the interesting question, Chris.

It'd be nice to diagnose the trouble before switching to an old oil burner or its parts, as I'm reluctant to blame the fuel unit.

First: I'd watch the flame during operation to see what it looks like when it stops. Is it increasingly smoky or does it suddenly peter out? Is there a clogged oil filter? Is crud building up on the electrodes? Will it re-start 30 seconds after shut-down or do things have to cool off longer?

Often an intermittent problem gets worse until it becomes a hard failure - not very convenient during the heating season, but easier to diagnose. I would prefer to find and fix the trouble rather than "shotgunning" by just starting to replace parts.\

But before swampping in an old fuel unit, I'd check the existing oil burner futher so that we don't waste effort or confuse things further.

There are several possible causes of intermittent oil burner failure that I can name and probably others that your service tech can suggest but that I've not thought-of.

- It may be diagnostic to note that your burner fails only after the system is up to full operating temperature or even is a bit hot.

That can sometimes point to a motor bearing or motor winding that opens in the drive motor or to a bearing failure in the oil pump or fuel unit.

It can also be

- A fuel unit whose coupling to the drive motor through the blower fan in the oil burner itself may be slipping - a failing coupling

- An oil burner that needs cleaning and adjustment

- A loose wire

- A cad cell sensor that's loose in its mount or is failing

- Intermittent draft problems

- water or debris in the oil tank, supply lines, filter, or fuel unit screen

- a failing transformer

- See OIL BURNER WONT RUN for a flowchart of diagnostic steps for an oil burner that won't start or won't keep running: what to check in what order.

Then, can you swamp fuel units? Probably, if the RPM matches AND provided it's the same type of fuel unit set-up (e.g. 1 line vs 2 line, number of stages, etc. ) you can swap fuel units.

Oil Leaks at the Oil Pump FAQs

What's the source of an oil leak at bottom of the the oil burner pump motor

What causes oil to leak from the small hole at the bottom of the pump motor (Dec 30, 2014) Walt said:

Reply:

Walt.

For a leak that is actually at the fuel unit or oil pump, I suspect a leaky oil line connection - in turn that risks improper or even unsafe burner operation.

Wipe the pump and nearby oil line fittings dry and watch to see where oil next appears. Let me know.

Fuel leaking around the oil burner pump shaft and burner won't run

I have a fuel oil furnace that won't do anything it has high and low voltage at primary control,

have jumpered r and w still don't run

have individual tested components all good solenoid valve

has small amount of fuel leaking around shaft what can I do next? On 2016-02-16 by Anonymous

by (mod) re: seized oil burner fuel unit (oil pump)

Sounds like a seized or failed fuel unit. The burner should be going off on reset.