We’ve collated some top tips for anode fitting, maintenance and identification of anodes specifically for Volvo Penta saildrives and engines. This manufacturer is one of the most popular brands and types of kit fitted on boats. Due to the range of designs suiting different vessel requirements, it also means there are are quite a few anode types to sift through. We often get asked about general anode fitting and maintenance, which anodes are required, where to fit them, how to match the original part numbers. This guide will help you cover off all of the questions above, and if it’s not covered in this article, it’ll be covered in another one within our Knowledge Base. We’ve tried to include as much as possible in this piece including photos of the different types, part numbers, links to the anodes and diagrams showing where to fit them whenever possible. What more could you need? A cup of tea perhaps?
Top Tips For Fitting and Maintaining Your Anodes
- Start by ensuring you get the correct anode for the job! Enter the Volvo original part number into our search facility to find the correct part. A few original part numbers have changed over time so there maybe a couple of different numbers for the same part. If you’re not sure, you can often find the correct part by using our guide to the different saildrive types, engines and propellers, and by entering the model into the search box.
- Clean the area where the anode is to be fitted ensuring there is no oil, debris or paint.
- Ensure the surface of the anode has a good electrical contact where it is positioned, both on the metal surface and through the bolts.
- Start to consider replacing the anode when it has corroded by 30% and definitely replace it when it has reached 50% as there will not be enough surface area or capacity in the anode mass to protect effectively.
- Never paint the anode or the area underneath, but do repair or repaint any area that was factory painted to ensure the anode is not being required to protect additional areas.
- Only use premium, ideally US MIL Spec grade anodes to protect your investment; never use home made or sub-standard alloys. For new vessels, check your warranty will still be valid using aftermarket anodes, you may not be covered regardless of whether they are exactly the same specification or not.
- Use the correct metal type for the water your vessel is in. Use aluminium or zinc for salt water, aluminium for brackish water and only use magnesium in fresh water. If you use magnesium in salty water types it will corrode very quickly and leave your vessel unprotected VERY rapidly
- Remember that the anode has only been designed by Volvo Penta to protect the part it is fitted to eg. saildrive. If you have additional metal equipment fitted below the water line then that will also require protection
- Use the same anode metal type across the whole vessel; you don’t want to create additional problems by mixing metal types. The only exception we’ve seen if on the IPS drive which has a combination of zinc and aluminium
- Anodes work by sacrificing themselves instead of the more noble metals. The whole hull set up should be tested while in water with a reference half cell to ensure that the vessel is protected on a holistic basis, not the individual component parts
- Check for stray currents in and around the boat; stray voltages and other metals in your water area will also affect the corrosion potential on your vessel. Volvo’s configuration does not require a galvanic isolator to be fitted unlike some other engine manufacturers but it is always best to check
- Lastly, inspect your kit as often as physically possible, that may mean a quick dip or with a camera. All it takes is for the boat alongside to be under-protected and you could well be left cathodically protecting their vessel and your anodes disappear
Which Anode Do I Need?
Back to the first point on our list of tips, find the right part(s). If you already have it, just type it into our search box. If you’re unsure what you need, use the guide below with information on each different type to help you identify the right anodes.
Click on the orange links to display matching anodes. Please contact us if there is an anode you can’t find listed. This list covers anodes for Single, Duoprop, S-drives, DP, SX and IPS Drives. It also includes engine, prop and shaft anodes for S-Drive models and Fixed Propeller shaft anodes in both metric and imperial threads.
Aquamatic Sterndrive – Single Prop Drives:This section covers the rings required for V15-V17 or Aquamatic 80-100, AQ200 and the AQ250-270.
Aquamatic Sterndrive – Single Prop DrivesThis section covers the 200-290 Volvo Penta Single Prop Types.
Transom Bar or Transom Shield Anode for AQ 200-25, 270, 275, 280 and 285. This anode is also part of a kit if required where you get both anodes for this model along with the bolts. Diagram below shows anode locations.
Transom Shield or Transom Bar Anode for AQ 280-290 and SP models. This is smaller than the dog bone style. This anode is also part of a kit if required where you get both anodes for this model along with the bolts. Here’s the position of the 2 anodes in situ.
Aquamatic Sterndrive – Duoprop DrivesThis section covers the 280 and 290 DP Volvo Penta since 2002.
Aquamatic – SX – DPS Drives
Aquamatic – SXA – DPS-A/DPS-B and FWD DrivesThis section covers the 2 anodes required for SXA/DPS Volvo Penta models.
The kit contains both anodes along with the bolts.
Transom Shield or Transom Plate Anode For SX-A and DPSA/DPS-A/B/FWD. Diagram below shows where this and the counterpart anode are fitted.
The kit contains both anodes for this model along with the bolts.
Aquamatic – DPH and DPR DrivesThis section covers the 2 anodes required for DPH/DPR Volvo Penta drives.
This plus the anode for the transom form the anode kit for DPH/DPR models shown in the diagram below.
Aquamatic – DPX Drives
This section covers the 2 anodes required for DPX Volvo Penta drives
Volvo Penta IPS Drives
This is the much larger version of the IPS1 anode and is available on request in zinc and aluminium.
Saildrive Anodes For 110S, MS25, 120S, 130S, 150S
Rings and folding propeller anodes fitted to the above models are listed below. Also includes modified versions to fit rope cutter and newer models where applicable.
Fixed Propeller Nuts
Prop nut anodes with various internal fit in metric and imperial – be sure to select the correct one!
Volvo Penta Engine Anodes
Pencils and plugs for all Volvo engines. Items available separately and in most instances in all 3 metals for all water types.