Aug 9, 2017

Inspecting PropInspecting the prop, strut, cutlass bearing and shaft anode

The moment we all dread. It’s a warm sunny day and you’re out for a cruise. Suddenly the boat shudders beneath you, pings, dings and clangs are heard and you realize that you’ve hit something submerged.

From a seamanship standpoint – there are many pieces of advice and rules to follow. To put it all succinctly: Get yourself, your crew and your vessel in a position of safety (whatever good seamanship requires), first and foremost. This should, in almost every circumstance, include taking the engine out of gear.

Once your vessel and crew are safe and secured, realization will slowly creep in that damage has been done, and that a repair bill may run high. Before panicking – let’s take a look at some common damage points, what your repair tech will look at to assess the damage, and what you can do on your own to keep your costs down.

Before taking any action when damage has occurred, you should speak with your insurance company. They may direct you to have certain work performed in certain ways (and your coverage may be dependent on following their instructions).

Dialing Prop Shaft Dialing a prop shaft

In most cases, when underwater damage occurs, the boat will need to be taken out of the water to assess damage (either trailered, or lifted by a travelift). This should be done as soon as possible after damage. Here’s a quick list of what you should be looking for:


1) Damage to the hull – including fiberglass, metal, wood, through-hull fittings, the bedding of through-hulls and hull anodes

2) Damage to the prop-shaft – some boats have a prop shaft running from the engine directly to the prop, others may have sail-drives or stern-drives. All configurations have a prop shaft that may have been damaged if an object has come in contact with the spinning propeller. Sometimes damage or bending can be seen with the naked eye, other times the shaft may have to a ‘dialed’ – meaning that a tool called a dial indicator is used to measure any bending in the shaft

3) Damage to the strut and cutlass bearing – on boats with a long shaft, a strut assists in supporting the weight of the shaft extending outward from the hull. The shaft runs through a cutlass bearing (mounted inside the strut) which absorbs heat caused by friction, as well as preventing the shaft from wobbling as it turns at high RPM. If the prop has impacted, causing the shaft to bend, the chances are high that the cutlass bearing may also be damaged, as well as the strut supporting the shaft

Props have been removed and gear lube drained to check drive and shaft condition after impact.Gear Lube Drained

4) Sail-drive and stern-drive gears: In situations where the propeller impacts an object on a vessel with a sail or stern drive, the prop shaft may be damaged or bent. Inside the drive units, the shafts are driven by a series of gears, encased in gear oil. In a situation where an impact has occurred, the gear oil should be drained into a clean pan, and inspected for evidence of metal filings which would indicate damage to the gears inside the drives. If particles are found, and the gear lube is darkened or smells burned, the drive unit should be broken down and rebuilt as necessary.

5) Engine couplers – the component that joins the engine to the propeller shaft is called the engine coupler. In a heavy impact, the shaft could be thrown so far out of true that the coupler is damaged in turn – which could also cause damage to the engine. The shaft should be removed from the coupler and both inspected/replaced if any damage is suspected

6) Speedometers and transducers should be inspected for damage and tested before relaunching. Speedometers can be blown with compressed air (causing the gauge at the helm to ‘jump) which confirms proper functionality

7) Trim Tabs – trim tabs work via hydraulics – the tabs themselves, as well as the hydraulic arms and fluid reservoirs should be visually inspected, and the entire system tested before relaunching

Andrew Macdonald8) Propellers, Skegs and Anodes – Damaged props should be removed and refurbished by a repair shop. Propellers that aren’t in balance can cause damage to shafts and engine couplers (and on a secondary note can cause poor engine performance and lack of fuel efficiency). Broken or bent skegs should be repaired and anodes replaced if cracked or lost.

It’s scary to think of underwater damage and the risks that go along with boating – understanding and being prepared are the best tools that we have for preventing damage before it occurs.

In the August 24 issue – Part 2: keels, keel bolts, dagger boards, through-hulls and protective measures: bilge pumps (electric and manual), bungs for through hulls and best practices for setting them up aboard.

Safe boating everyone!

Andrew McDonald

Ask AndrewAndrew McDonald is the owner of Lakeside Marine Services – a boat repair/maintenance firm based in Toronto. Andrew has worked in the marine industry for 12 years and is a graduate of the Georgian College ‘Mechanical Techniques - Marine Engine Mechanic’ program

 

 

 

Related Articles
Maintenance
  • 28 May 2020
  • By Ethan

Cored Deck Repair

It’s race night and the breeze is strong. Sails are full, the rigging is taught and the crew are working hard. Footfalls hit the deck and bodies move across the cabintop. The boat is tacked and...

How To and DIY
  • 26 May 2020
  • By Ethan

Ask Andrew – Interlux webinar

There’s no doubt that the COVID-19 pandemic has changed our world. Some of the changes are huge: social distancing, sanitizing and face-masks have become our new norm. Adapting to working from home, and...

Lifestyle

  • Prev
The seasoned sailor mapped out an ambitious course around the world — aboard his 28-foot ...
Clean wake: A concept amongst cruising sailors that stresses the impact that individual behaviour ...
This line-up of Beneteaus can to us from our friends at RCR Yachts in NY State where they are ...
As another harsh Victoria winter came to a close, the deck repair and refinishing continued with ...
The Peterborough Canoe Company was formed in 1892 and began production the following year after ...
On one of the sunny days we had recently, Kyle MacTaggart in Honey Harbour ON fired up the Merc to ...
For all those OnBoard subscribers who have followed along with the maintenance, repairs and ...
We hardly need tell you about the pandemic but it’s worth noting that the marine industry is acting ...
If you’ve been to CORK, you’ve probably seen Tim Irwin. Whether he was organizing volunteers, ...
This brilliant shot comes to us from professional shooter Elle Bruce.  These four sailors are ...

Boat Reviews

  • Prev
New at the end of 2019, the 58 Salon Express design features large windows to flood the living ...
No wonder this is one of Regal’s best-selling boats; the Regal 33 Express offers amazing ...
The newest member of Beneteau’s Gran Turismo line is the GT 36 and this yacht brings the style and ...
With a philosophy of quality and 'doing things right Ranger Tugs launches the all new R-25 at the ...
The new Beneteau Swift Trawler 41 renews the spirit of the practical seaworthy cruiser. The ...
The Canadian Yachting test crew last week had the opportunity to run the Bavaria S36 HT at St ...

CY Virtual Video Boat Tours

Virtual Boat ToursWe all love boats and nothing can break us up! So, what better way to spend our time than looking at interesting boats and going aboard in a virtual ride or tour. We have asked our friends at various dealers and manufacturers to help us assemble a one-stop online resource to experience some of the most interesting boats on the market today. Where the CY Team has done a review, we connect you to that expert viewpoint. Our Virtual Show will continue to grow so visit frequently and check it out. If you can’t go boating, you can almost experience the thrill via your screen. Not quite the same, but we hope you enjoy our fine tour collection.

 

Read more about the CY Virtual Boat Tours....................

Destinations

  • Prev
On May 19, the New York State Canal Corporation today announced an updated opening schedule for the ...
If you have four hours to enjoy a fine tour of one of Canada’s most interesting waterways (let’s ...
Boom & Batten Restaurant is suspended over the water adjacent to the Songhees Walkway and ...
Provincial Boat Havens are those special places to drop anchor in British Columbia’s West Coast and ...
NW Explorations, a Bellingham, Washington-based yacht charter, brokerage, and marine services ...

KingstonBy Amy Hogue

Cruise into the city of Kingston, Ontario, and it will quickly become clear that this city and surrounding waterways have something special. Built around the northern shore of Lake Ontario, Kingston is the place to go if you love to explore new waterways, fantastic views, and exceptional boating opportunities.

Sitting at the intersection of three world-class Canadian bodies of water, Lake Ontario, the St. Lawrence River, and the UNESCO World Heritage Site, the Rideau Canal (Cataraqui River from Kingston to Newboro), the water’s influence is deeply woven into Kingston’s culture and history. 

Read more about Kingston...........

 

Marine Products

  • Prev
The new 2020 PORTS Georgian Bay, North Channel & Lake Huron Guide is available for purchase at ...
Professional boatbuilders don't want to have to redo a job any more than a DIYer. Many choose Life ...
Since its introduction last year, the JBL by Harman Marine BassPro 10" Powered Subwoofer (JBLMBP10) ...
After decades of perusing charts and guidebooks as part of planning a cruise, it was a totally ...
Ever since I was a youngster Jeeps of all kinds have fascinated me. It wasn’t until the mid 70s ...
New from Plastimo, this bi-colour backpack in Tarpaulin 500D will keep contents dry from ship to ...
Being a boater can come with certain space restraints for additional items that may make your ...
Whether you are interested in monitoring your vessel’s systems while underway or remotely from your ...
No wires to install down your mast. Transmit to smartphone/tablet. Works with lots of great ...
Vesper Cortex, the advanced multi-station VHF, AIS, monitor with intuitive touchscreen operation is ...