Last week, I mentioned the Deutz generator package we have in for an overhaul due to damage found during a borescope inspection following reported excessive smoking.
(Click here if you missed it.)
The generator is in the workshop now and the engineers are busy on the overhaul process, beginning with inspection and dismantling.
During this stage, the ability to dismantle for inspection has highlighted further issues including the following:
• Excessive corrosion in pipes, oil cooler and liners
• Turbocharger turbine wheel has edges of vanes broken, requiring replacement
• Water pump removed to show a blocked elbow with heavy corrosion inside
This damage can be traced back to this; a heavy build-up of solidified antifreeze, which has severely restricted the flow through the water pump inlet:
There are several reasons why solidification has occurred leading to the restriction in water flow in the engine.
As the engine is a backup generator, it is rarely run – around once every 3 months for an hour or so with no load. This is due to the requirement for the DNO to attend and disconnect power to the whole building to do so.
Also, with the blue antifreeze, it is recommended it’s changed every 2 years, and we have been informed this has not been done for almost 20.
With the set being such a critical piece of equipment, and now knowing the difficulty the operator has when it comes to running on load when required, we can give them the option of utilising our loadbank onsite when required up to a maximum of 600kw.
It is suggested that a loadbank test is carried out for 2 hours every year, or two years at most.
This will give the operator peace of mind that the engine will be reliable when called upon and prevent common generator related issues such as the solidification of anti-freeze which – as we can see – leads to far more serious concerns.