Screaming Mectron 3BM Oil Boiler

[David Caple]

Hi all, first post!

I shut down my Mectron 3BM oil boiler some 5 - 10 years ago when the price of oil became unacceptably high. But with the price more than halving recently I decided to get 2,000 litres in so with a nice full tank I bled the system through, switched on the power and fired it up ... it lit first time but then came the usual 'but', it was screaming! I suspect a dry bush (don't know what it spins in until I delve deeper). Could it be a bush that has gone dry with it standing idle for so long? If so is it a strip down job or should I look for some form of lubrication facility?

I have no idea of the make-up on the motor/pump arrangement and while I'm happy to apply a spanner to anything I like to check my options first.

Hoping someone can remember these old boilers.

 

[Burnerman]

It'll have one of the oldie but goody Riello burners, David - and the screaming will be from either the motor itself, with dry bearings, or the oil pump - unfortunately no external lubrication is possible so dismantling is necessary.
The motor bearings are dead cheap - the oil pump somewhat less so. Purely at a guess I'd think it was the motor.
John

 

[Terrywookfit]

Or a restriction on the oil suction line.

 

[oilhead]

as above, but also check the hydraulic ram for leaks. It won't be the cause of screaming, but can be a very annoying smelling leak.