Riello RDB Oil Leak

[RBZ5416]

I appear to have a small leak from the oil pump. Looks to be coming from the joint between the pump cover & main body. But that's only based on where the oil lands on a piece of kitchen roll placed under the pump. I can't actually see it as it's both inaccessible & just a weep. So could potentially be leaking elsewhere & gravity taking it to the lowest point.

I've tried nipping the four allen screws a touch tighter but to no avail. Google seems to suggest that there's a filter & gasket in there so I guess I need to replace the gasket? Can someone please point me to the correct parts?

As an aside, the leak started immediately (well next day) after the latest delivery. Just coincidence or could something be wrong with the oil? Having collected some of the leaked oil it is yellow, where all the online videos I've seen when researching a different issue on my Mother's boiler show it as red. No idea if that's relevant?

The delivery was also a top-up from half-full on a 1200 litre tank. So at worst would have been a 50:50 mix with the old oil that wasn't leaking. So I'm tending towards co-incidence.

 

[muggles]

Oil is almost always yellow (kerosene) not red (agricultural diesel) in the UK. They aren't interchangeable, you must always use either one or the other. Incorrect fuelling will cause a breakdown and may cause irreparable damage as well.

You might get away with a new seal and filter, but I have known these pumps to leak from the casting, in which case a new pump is required

 

[oilhead]

I would be inclined to suspect the shaft seal, with the oil creeping to the lowest point. To check, undo the nozzle feed from the pump, loosen the allen screws securing the hub into the motor, and withdraw the pump. Look into the back of the motor and the bearing should be dry. If it is wet, there is your leak. Before replacing the pump, undo one of the connections to the coil and start the burner for a few seconds. As it slows, it should be silent. If it is noisy as it slows down, you may as well replace the motor at the same time. If the pump has been leaking for a while, it will have been flooding the bearing. Once you put a new pump on, the bearing will become noisy and scream. It is possible to replace the bearing, but as a professional, what I would charge in labour brings the cost up towards a new pump.

 

[RBZ5416]

Thanks guys.

Dismantling sounds a bit above my pay grade so as it's due a service anyway, think I'll get a Pro in.

A bearing was replaced last time it was serviced a couple of years ago as it was noisy. Noise levels were reduced but not completely, although it's hard to remember what they were like originally when you've lived with noisy for a while! I seem to recall that there were two bearings involved, one of which was much easier to get to & therefore cheaper to replace in labour terms. That's the one that was replaced.

If I'm looking at worse case scenario of motor & pump, what sort of ball-park figure am I looking at? Unfortunately the village specialist that everyone used has recently retired. So as I'll be starting from scratch when looking to book someone, an idea of likely costs would be helpful.

North Essex if labour varies significantly.

 

[oilhead]

Find a pro first. I would be looking at around £250-£300 to replace items and service boiler, but I'm not in north Essex.

 

[oilboffin]

I'd make sure it's not leaking from the stem that the solenoid sits on that's a common place to leak from.Bob

 

[RBZ5416]

Thanks again.

Any tips for cleaning the pump body completely of oil so I can hopefully see any leak or new deposits?

 

[oilhead]

As I said, you need to remove the pump to identify exactly where the leak is; oil tracks.

 

[RBZ5416]

I'd make sure it's not leaking from the stem that the solenoid sits on that's a common place to leak from.Bob

Looks like you're right, the solenoid & valve stem were covered in oil. Given that the valve is OK, presumably just a case of replacing the O ring?

Given that the locking nut sits it a recess on the pump body, what's the best way to remove it, box spanner? I did find the knurled nut that locks the solenoid in place on the floor. So wonder if it's absence has caused vibration.

 

[oilboffin]

If I were you I would just replace the whole pump lot less hassle,while your at it change the oil hose
For a long life one aswell.Bob

 

[RBZ5416]

While I wait for a pro to service it & give an opinion on motor/bearings, I've replaced the needle valve (£17) & the leak is cured. Not sure I'd agree that changing the pump would have been easier for a novice, given the limited access to the securing screws. Looks easy on a bench but less so at floor level in a dark cupboard!

This boiler is a Warmflow 70/90 from 2001 & I simply can't fathom why they didn't fit an inspection panel to the LHS cover to give easy access rather than having to wrestle the entire cover off, including four self-tapping screws from the back. Although I guess you guys have tools of the exact length to work in these confined spaces?

If it helps anyone else, removing the two screws securing the control box gives better access to the valve. But as I said previously, the 15mm securing nut is both shallow & recessed & a real pig to get a spanner on. I just about managed it with a set of flat spanners I have for adjusting bike cone bearings. There's no way you'd do it with a regular open or ring spanner, never mind an adjustable. So I guess box spanner is the tool of choice but not something I own. Don't by be tempted by mole grips or pump pliers on the valve body as the brass is thin & you'll kill the valve!

Thanks to all who posted & especially to Oilboffin for pointing me to the valve in the first place.

 

[oilhead]

If you first remove the burner from the boiler by undoing the single nut at the top of the flange (this is why it is connected with a flexible hose), you will find the RDB is one of the most accessible units available.

 

[oilboffin]

My pleasure just glad to help.Bob

 

[RBZ5416]

If you first remove the burner from the boiler by undoing the single nut at the top of the flange (this is why it is connected with a flexible hose), you will find the RDB is one of the most accessible units available.

Now you tell me!

Oh well, next time...

 

[Amol Karnik]

Hello. Reviving this old thread in the hope of finding some help.

My Grant boiler had an Riello 2.2 burner. I have been smelling oil for a while now but it's got much more intense with the boiler running more as winter sets in.

I have found oil droplets on the left hand side of the unit ( side closer to where hoses enter the unit) but I am unable to find the exact source.

I imagine it would be easier if I removed the unit from the boiler housing.

Can anyone offer tips on the best way to troubleshoot.

The boiler is around 10 years old but has been in storage for approx 3 years and has powered an eco home for the past 4 years so doesn't get the type of use that it might normally get if this information is of any relevance.

TIA