Old from 1960/70 era pmx6 5.5hp Yanmar parts issues

[bouncycastle]

Old from 1960 era pmx6 5.5hp Yanmar parts issues

I have found for very cheap E100 euros a Yanmar 5,5 PMX6 era that was working a few years back seems they are from the 1970 era

Are spares available still for these engines as it look like it fits my boat engine room very nicely

If not will pass on it and look for 8 to 10 hp but its tight space for bigger engines as boat 8.7 meter era 1969 made for 8hp petrol when i bought it 2019 came with
diesel 2 pot 2000 era 14 hp bigger engine that is really to big for the engine room and uses too much fuel per hour

bouncy castle

[skipperpete]

Originally Posted by bouncycastle

Old from 1960 era pmx6 5.5hp Yanmar parts issues

I have found for very cheap E100 euros a Yanmar 5,5 PMX6 era that was working a few years back seems they are from the 1970 era

Are spares available still for these engines as it look like it fits my boat engine room very nicely

If not will pass on it and look for 8 to 10 hp but its tight space for bigger engines as boat 8.7 meter era 1969 made for 8hp petrol when i bought it 2019 came with
diesel 2 pot 2000 era 14 hp bigger engine that is really to big for the engine room and uses too much fuel per hour

bouncy castle

Hi again Bouncycastle, I had no idea what Yanmar model this 5.5 hp engine is so I did a search and found a few, some in museums and some still running happily in canal boats and I think your concerns about spare parts are well founded. I agree that the PMX6 is a good fit for your engine space but would suggest a 1GM 10 as also a good candidate for your restricted engine compartment and a bit easier to get spares for . You’ve been without an engine for quite a while now, hope you’re ok.

[bouncycastle]

The issue for me is not so much the cost of Diesel fuel i get with 14hp at 70% gas about 10 Nautical miles to the gallon

My target this year is go to Norway where i have friends
Then after that down to Gibraltar and then across the Med to Turkey and back to Gibraltar the Spanish Cananary islands for the winter then back to Norway next year 2024

In northern latitudes in Summer i calculate about 20% engine use at 3,5 knots for fuel saving and 80% sailing
South of Porto spain i calculate 50% sailing and 50% motoring at 3.5 knots

from Gibraltar to where fuel is cheaper to go across Mediterranean to Turkey in Summer it more like 80% motoring at 3,5 knots and 20% sailing .Then return to Gibraltar might be more sailing as autumn winds kick in . Then going to Canaries island willing to allow more drifting time so less fuel useage both to go there and return to Norway as less scheduling


The 14 hp uses as per formulas at 70% gas 3,5 to 4 knots about 10 hP at 0.4 lbs fuel per HP or 4 lbs per hour or 2 litres per hour or 10 to 11 nautical miles per gallon imp possibly marginally more
At speeds of 4.5 knots due to unsuitable prop and 14 hp much less Nautical miles to the gallon
Big fly wheel seems to work best at full tilt where modern engines seem to be better at 70% gas

My previous boat 27 foot with old fly wheel SAAB 9 HP used at full tilt 5 knots about 1.5 liters per hour or 3 hours one gallon imperial or 15 miles per nautical mile gallon possibly as high as 18 nautical miles to the gallon

For most journeys i did with the 14 HP some 200 hours running before engine seized up carried 220 kgs of fuel about 250 litres
mostly in 5 gallon 20 liter containers on the deck and stored below for technical problems to get easy access for fuel at many ports


A 5.5 HP i estimate can give me about 3.5 knots full tilt and possibly give me in calm seas as much as i liter per hour or closer to 22 nautical miles per gallon

If plans work leaving Low fuel tax Gibaltar with 250 liters or 83 gallons imperial that could give me a range of some 1100 Nmiles versus 550 Nmiles
for the 14 hp

In the case of the med pulling into ports and refuelling costs a lot in summer in time money and often marina cost such as Italy and Malta

So its not so much the cost of the fuel per liter but other factors times of the year and sailing grounds dictate max engine ranges can save a lot of money in long distance tours

I know the best saving is sail and no engine but thats not easy to do withemediterain fickle winds and port to port hopping been there done that got the T shirt

Yes a good for stroke petrol can be usefull but 250 liters of gasoline isnt my idea of fun compared less flammable and more safer diesel fuel If Natural gas wasnt twice the cost of diesel fuels use It could be another solution with a some 20 of the 11kg gas bottles stored some place

Failing being able to get parts for the Yanmar PMX6 or PMX 8 that means I might look to get 7 or 8 HP motors i think older Volvo was some 8 hp

India sells a lot of old hardly used SAABS 9 hp but parts for those often need to get from India and then in communist controlled EU tax and imports adds a lot of extra costs


Turkey makes and online sell on e bay non OEM parts for many marine engines but they seem to not know what they sell. To fix my 14 HP i need two cylinder bore out as it is a solid block engine .Turkey Ebay claims to sell the cylinder lining for the my 14 HP but when i checked with EU and UK agents they both say impossible to liners for the 14 hp engine

So I will continue the search to get parts for the Yanmar PMX6 engine until i am sure the parts are unobtanium parts as 6 HP will suit my long term needs for best Nmiles per gallon

Thanks for the Canal info will try that

[skipperpete]

I would suggest a lifeboat engine from the ship wreckers in Chittagong or Alang but even the smallest of these engines is larger than what you could comfortably fit into your engine space.
Given the ambitious cruising plan I think you really need to get a reliable power plant, maybe a Betamarine or a Solè mini, preferably not second hand.