“Tee – Eff – Bundy” … Monday 2nd April 2018

“Tee – Eff – Bundy”   …   Monday 2^nd April 2018

“Tee – Eff – Bundy”, or to be precise TFBNDY, is a 6 letter acronym that is apparently used by doctors to describe patients with a less than stellar prognosis. It stands for “Totally F…ed But Not Dead Yet”, but it's a description that would fit the impellor on our engine perfectly. This morning we focused-in on a bunch of boat jobs, including changing the oil and replacing the impellor. The “impellor” is an 8-blade rubber paddle wheel enclosed in the salt-water cooling pump on the engine. It's supposed to be changed every 600 hours but it’s probably been twice that since ours was last changed. Poor maintenance on my part and my only excuse is that it’s been working fine and it’s a bugger to change. I set out on this task with some trepidation, worrying that it was an unnecessary operation that I could totally mess up. To gain access to the unit you need to reach under the sink, through a removable panel on the side and then past a bunch of hoses and cables. The backing plate for the impellor faces the rear of the engine and is partially blocked by the starter motor. In short you need to be a contortionist to get to this thing. As soon as I had removed the backing plate it was obvious to me that a replacement was needed; there were clearly parts of blades missing. However, it took me another 30 minutes of intense struggle to pull out the old impellor from it’s housing. In so doing I probably stripped off another 1 or 2 blades, but the unit that I took out only had 2 intact blades of the original 8. It was a miracle that it was functioning at all and I think we were perilously close to having a complete failure and engine over-heat. I’m honestly not sure that I could do this replacement underway at sea because it’s just so fiddly and difficult to get to. I think we dodged a bullet here. (Check out the picture below for a comparison of the impellor we replaced today, with another used one that we replaced a few years ago and kept for emergency use because it still looked fine). The final part to this story is that when we test ran the engine I was deeply concerned that there seemed to be no water coming out of the engine exhaust – an important indicator that the cooling system is working. Did I screw it up so badly that the pump doesn’t function? No … I simply forgot to re-open the salt-water through-hull so the engine can access cooling water. It took me a nervous moment or two to realize my error, but now it seems to work just fine.

Mike

On the left is the impellor I removed today, on the right a used impellor that I removed a few years ago (and kept as a spare). I am amazed that our engine wasn't overheating but the gauges looked OK.

Water lily

Water lily pod after flowering

Water lily pod dried and old