Presumably, air cleaners are about dusty environments, and dust is a rare thing on the water. But is the engine room actually clean?
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The Volvo Penta D2-55B engine silencer (air filter) is pretty cheaply made and very expensive to OEM replace. Being made of a center spring wrapped in foam (each sold separately) makes it a joke. After some frustration I settled on a K&N filter (RU-0810) that is much better made and cheaper. However, K&N doesn’t make it easy because that aftermarket replacement was determined only after measuring the engine air opening diameter and available space for the body of the filter, i.e. they don’t index their products for specific Volvo Penta engines and I found their search menu somewhat difficult to use.
~ ~ _/) ~ ~ MJH
I have a Valve D2-40 in my boat and changed from the original Volvo air filter to the KN model. Never looked back, perhaps a little more noise, but very little, I would highly recommend this to any Volvo small engine owner. Out of interest other mods have been changing to the Razor style fuel filter and recently a stainless exhaust elbow.
I have had a K&N filter on my 4-108 since 2007. No problems. I simply terminated the crankcase vent against the filter. Needs periodic cleaning.
When I remember, which is about 2/3 of the time, I pull the filter clear off when we lose sight of shore. Don’t know if it makes any difference or not; increases noise, but not a lot. Crankcase vent repositions to just over intake.
One of the most important functions of a marine engine air filter is as a flame arrester. Saw the result of an engine on an inboard with no filter. It backfired, set the boat on fire as it was motoring past the mooring in Weymouth UK harbour. The two people aboard jumped overboard and the flaming boat drifted alongside a sailboat, doing extensive damage. Boats are particularly vulnerable as propane, gasoline, oil etc accumulate in the bilges. A wire mesh is an effective arrester and a foam or paper filter should incorporate a flame arrester..
I gladly own a perkins turbo diesel 356 cu. Inch 6 cylinder. Perkins made the small CAT engines in the 70s and 80s.
I installed a CAT air filter purchased from a local equipment rental business. With some threaded rod and an end plate it’s on. Best think is the turbo whine is now muffled. With bilge ventilation I doubt air intake contamination is an issue. PCV are installed in engines to maintain vacuum in the crankcase. You don’t want cranks pressurized. That would blow oil seals and o rings.
Converted from a cast iron fitting, oil bath, air filter to a much simpler and lighter K & N. Bought a bent stainless tube, cut to fit, drew a pattern for the DIN gasket sized mounting flange and had a shop cut the flange and weld together. Fresh water boat, Farymann engine, so lots of the same parts probably used on shore in potentially dusty conditions, and we race so less weight easy to rationalize.
The breather oil recovery bowl is missing on the first photo – it still is somewhere under the engine. I’ve replaced it with another just like it. You really should publish photo credits…. Second time for me in this periodical.
I collect 1 per 100 engine hours so cleaning the catch bowl is done with an oil change. I’ve improved the engine slightly since this picture – which was taken for an article in the Catalina MainSheet, I’ve added a heim joint turnbuckle to tighten the belt, which has reduced the dust in the engine bay.
Btw – the remote oil filter shown has made changes much less messy
How would an “emergency stop button” be of any possible use in the event of engine runaway fueled by crankcase oil?
The only remedy in this situation is to have a mechanical (cable) air intake shutoff such as those found on GM two strokes of yore.
It might take a good deal of engineering in order to fit something like this on a tiny sailboat auxiliary’s intake silencer.
@Warren Agreed, to stop a runaway, you must remove air from the combustion as the fuel is out of reach. On small sailboat engines you do not need anything complicated. Blocking the air intake will work. Use a book or a board, just not your hand. It is good to know where the intake is and have a plan.
on my sailboat I rely on a VP MD2040.
Many yars back I came to realize that the VP foam filter is a piece of shit and (last but not least) a real rip-off.
So 10 years ago I disposed of the foam cylinder but I salvaged the inner metal spring and I wrapped around it a piece of the 2-layer (blue and white) cloth that is of common use for air conditioners. Cheaper than fools. I think I paid less than 4 Euro for a couple of square meters and I have yet a large piece for spare. I change the cloth every year (as I said wrap it around hte spring with the light blue layer on the outside, clamp it on the collar of the exhaust and trim the excess with a scissor).
Cheap, effective and reliable.
I have two Penninsular 6.5 lt Diesel engines on my boat (turbo charge). Penninsular was acquired by Unique Marine about two years ago and now they announced that they are negotiating their parts department and they won’t be able to dispatch parts until then. I need to get the air filters for my turbos (the ones I have are the foam covered). Cons you recommend a good replacement?