Sailing Vessel Karma

So the story goes we are re powering Karma! We are slapping in a 2GM20F in place of our well used and well loved 2QM. The first funny thing we learned was that what we have is not a 20 HP engine, but an 8 HP.

Since we got the boat and was told from the previous owner it was a 2qm20, we considered it such. I have poured over the manual since we got the boat for the 2qm and 3qm series with all its variations (F, H, Y, B). It walks and talks like a 2qm20y, with a continuous output rating of 20 hp at 2,600rpm. Realizing we actually had an engine plate after replacing the starter a week ago, we attempted to read the Japanese alongside some numbers. “(PS) 8 (rpm) 1800 (rpm) 818 and 2.20″….PS = piston speed of 8 m/sec?? The 2qm20y is rated at 7.8 – 8.4 m/sec but why would the heck that be on the plate…and what is this low 1800…..that’s our engine speed?? The 2.20 surely is the gear reduction ratio so the 818 would be our propeller speed. With a call to trusty Mitch in the San Juans he broke the news that the strange 8 has got to be the horsepower. 8!.

With no tachometer, we once used a metronome to get our cruising revs. We divided 5,200 noises by 2 cylinders to get 2,600 rpm. Mitch pointed out that the 4 stroke cycle means we should have divided again by 2…so 1,300 rpm makes more sense for an 8 hp 2QM. Re reading a handy classification website, clarification was had where confusion reigned; the last “20” in “2qm20” indicates a more powerful engine they got by taking the plain ole bb 2qm and boring bigger holes. Same thing for the 3qm series. So indeed there exists an actual, plain, 2QM engine and it’s in our boat. Only distributed in Japan initially, where the boat was built.

This is not why we are repowering though. Our transmission has been derping hard. It was stuck in forward starting a few weeks back and we could only sometimes move to neutral. We sailed to Tofino, the towering metropolis of the West Coast, hoping to discover a mechanic. We only found Rod’s/RPM shop which sells things and does many an outboard work. After a million calls sourcing parts availability for a rebuild ourselves, if a shop would/could rebuild it, compatibility of replacements, we deduced that this transmission is 1) funky 2) difficult to get parts for 3) not compatible with other common ones eg Kanzakis. Unrelated of course, we decided that forward is quite a noble position to be in; we would just sail to Mexico with a unidirectional engine! People do it without engines. People have voyaged with only reverse! Plus we have the dinghy with an outboard, of comparable size to our inboard…Tofino held us up for a few days with the beaches, a kind German, weather window waiting, and the tastiest of beers: Tofino Brewery’s Spruce Ale oh my goodness.

Upon hearing that “there seem to be more sailboats in Ucluelet,” we finally went south. We anchored Karma in a place compared to the busiest street in downtown Chicago by a new pal Steve on Wendy and their lovely Valiant 40. Few days later, we tried starting the engine one last time to move locations, we confirmed we needed to repower since it would not even turn over. Our first dinghy assisted anchoring took place with some difficulty.

Night one in Ucluelet we ran across a boat of youths enjoying an evening chat on a cool Sceptre 36. Keith invited us on and fed us beers. He and Raven have been sailing around the island, a trip total of about ~30 days. We swapped stories including our current fiasco. Keith offered a number of a man in Sidney who operates a boatyard and often has spares lying around from scrapped boats. We called him up the next day; within seconds he says, “Oh yeah I just pulled out a 2GM20F from a sailboat the other day you could have.” What a dream this Steve. The footprint is basically identical, rotates the same way, it has more power (16hp/3400rpm), it is the next generation of the Yanmar series, folks know the engine and transmission better, parts are more available, and it has about 1800 hours versus our 3,000+. Keith even offered the engine a ride in his vehicle when he returns to Ucluelet by land in a week! How nice to be connected to other places by road again. And surrounded by kind folks. Although this engine is more powerful, we have a few options to make the higher engine speed work with our propeller. The propeller shaft is likely oversized currently at 1 1/4″ dia.

2QM
8hp/1800rpm with a 2.20 gear ratio // prop speed: 818 rpm
2GM20F
16hp/3400rpm with a 2.36 gear ratio // prop speed: 1400 rpm

To avoid messing with re pitching or replacing our prop, we plan to simply not reach beyond ~2,000 rpm engine speed (1930/2.36 = 818) so we semi match the current set up. Once it’s in we will test our speed against different rpms and call a prop shop; it might be alright as is. And we’ll just sail a lot more if it’s really not.

We started dismantling our bb engine on 8/24/23 and still plan to cruise down the West Coast within a month! You know, being veterans at this now, starting day two (2) of this whole re power dealio, we really don’t see why folks make such a big deal of it…………

Day 1: 5 hours

• Electrical panel moved aside
• Oil drained
• Coolant drained
• Heat exchanger removed
• Exhaust removed
• Fuel disconnected
• Throttle and shifting cables disconnected
• Sea water disconnected
• Propeller shaft coupling bolts loosened (4 of 8)
• Engine mount nuts and bolts loosened (2 of 4)

Now to remove the engine and bilgecoat! Hopefully we are twiddling our thumbs by the time Keith makes it here with our shiny new engine.