This week I’ve been onsite to change two low-pressure turbo cores and replace the core o rings on a Paxman 12VP185 generator engine.
I attended previously to carry out a non-intrusive survey and health assessment of the set, and as you can probably guess, that survey flagged up a couple of things that needed attention.
During the survey, I found numerous oil and coolant streaks on the engine, one of the first alarm bells.
However, without seeing the set running it’s difficult to assess whether streaks are from previous leaks that had been rectified or from present leaks.
The more I looked, the better the indication though – many areas had oil streaks and seemed fresh, and the paintwork on the turbochargers had been disturbed, suggesting they have been removed at some point in the past.
I also noted that there were significant amounts of oil and coolant under the engine on the bedframe – this suggested that any present leaks had been there for some time.
Catch trays and mats were also present under the engine, indicating these leaks are a known issue.
These leaks in themselves are an issue to investigate, but the real problem was still to be discovered…
Oil was present in the condensate drain catch containers, and as the VP185 uses two-stage turbocharging technology, more condensation is produced than standard engines, through twice the amount of charge air compression and cooling.
Oil SHOULD NOT be present in these drains or anywhere else in the charge air system, as it could result in a complete loss of control of the diesel engine and catastrophic failure.
If enough oil is present in the manifold, the engine could run away, and if the cause is left completely untreated, it will get progressively worse with each prime cycle and run and slowly block the air side of the charge air coolers, which would affect the performance.
There would also be a steady loss of oil until eventually there wouldn’t be enough left in the sump to lubricate the engine.
Upon further investigation, we worked out that it was a turbocharger issue, as they have been removed previously, and several of them were found to be leaking.
The seal between the low-pressure outlet pipe from the turbo and the intercooler had drips of oil on the bottom, and the oil level was checked and found to be well below the minimum mark on the dipstick.
It was extremely fortunate that the low oil level was noticed during this survey.
If this survey had taken place a few weeks later, it is possible that the engine could have run out of oil leading to catastrophic engine damage.
The takeaway here is twofold:
- A thorough weekly checklist should always be performed to assess and monitor your engine’s health. The oil level, preheaters, and water level as an example should be checked before every planned start.
- Fast rectification of issues is vital to avoid failure, expense, and downtime.
