Riello Oil Pumps - Repair?

[Warm n Safe]

Hi Guys,
Over the years I have collected quite a supply of Riello oil pumps, many seized solid, but recently I have had a few, mainly RDB pumps with a different problem.
Due to the cost of oil, many customers are using 20 litre drums to keep their heating going - coupled with this is the practice of shoving blocks under the end of the tank to get the last bit out of it. Hey presto! Water in the pump!
I expected the pumps to stop, that's fine, but I've cleaned the pumps out completely, re-assembled, lubricated, and they are spinning freely.
When I put them on a burner I am getting absolutely zero pressure, not even a washing pressure! Looking at them there doesn't seem to be much inside, so what's the problem?
I figure if I can get them going ok they would be very useful on maintenance contracts - (covers call-outs and parts)
Any help or suggestions would be very welcome, it's doing my head in!

 

[Dotty]

My experience is once they're done, they're done. The tolerances are so fine during manufacture.

False economy trying to repair them tbh, as you've discovered.

Just carry a couple of spares.

 

[Warm n Safe]

Thanks for the quick reply Croppie!
I always carry spare ones, but it just seems frustrating, some of the pumps were only a few months old!

 

[Dotty]

Riello can't even repair them which is why they put around a disclaimer a few months ago denying the warranty on pumps that have been damaged by contaminated oil.

 

[Warm n Safe]

Yeah, I remember seeing that one alright!!

 

[lame plumber]

these little bunnies are made to such small tolerances that you opening them up screws them for good, bit like messing with diesel fuel injection sytems in your car, its just a no no

 

[Best]

You can open them if you are careful, but it is risky.
Problem is when you take the cover off the gearing - got to make sure you keep that side facing upwards in case it all falls apart. If you are taking the gearing out, you must be sure to be able to have them
in the same meshing again, - if you don't pump will sound rough!
If the pumps are spinning freely then you should have pressure unless the drive to first gear is slipping.
Use Riello pumps for scrap steel! Danfoss are in a different league.

 

[WHPES]

Unless there's basic faults such as leaking oil seals or gaskets, life's too short to mess about taking pumps apart.

 

[kimbo]

some guy used to sell parts to repair these on ebay for about £10 I bet he found some mug to buy them

 

[SimonG]

If a pumps not working its donald ducked. Fit a new one, if that one fails at least you have somewhere to go. If you try to repair it and it fails then its you thats donald.

 

[Warm n Safe]

Thanks for all your interest and comments guys. I might have enough when I scrap 'em to buy 1 new one! Lol