We were called by a marine operator seeking rectification for a failed Woodward 3161 governor.
Immediately after the start-up of the engine, the engine made a loud noise and stopped.
When the engineers on board went to investigate they found oil everywhere – (unbeknownst to them, it was due to the governor blowing oil out at 250 psi!)
They refilled the governor and tried to restart the engine, but of course, they had the same issue.
After a quick call to us, it was in our workshop ready for Andy, our governor specialist to work on it.
It was dismantled and the castings were cleaned as part of the investigation, and after he had lapped and tested it with engineer’s blue, it was apparent that machining would be required on the main body, which was carried out in house by our machinist who removed just 0.003” bringing it back to level and keeping it within OEM spec.
You can see from the pictures below that the base is free of issues, completely covered by the blue, but the main body has been warped.
We believe this is probably due to being overtightened and is a common fault on these governors – the bolts holding the base on go around the outside with no support in the middle.
The gasket had also failed where a pinch point was created and would further explain the loss of oil through lack of sealing.
Andy also found that the speed setting shaft had worn splines and will need replacing – this is also common with manually controlled governors as the vibration through the control lever causes damage over time. If left it would lose contact and therefore control, causing the governor to slip back to minimum speed.
As the operator’s vessel has another of these governor’s, which has the same hours as this one since the last overhaul, and likely the same damage to the splines – they are sending it in to us to be overhauled too.