Theduke1948
Member
I am thinking of replacing a Ford Lehman 120 with a Yanmar 4jH110 common rail Diesel engine. The boat is a Blue Seas 36 at 12 tonnes. Any thoughts? Has anyone done this?
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Not familiar with that Yanmar. Believe they run at a significantly higher rpm. You may have issues with getting tall enough gears (transmission ratio) to be able to use your existing propeller. Just another added cost to consider.I am thinking of replacing a Ford Lehman 120 with a Yanmar 4jH110 common rail Diesel engine. The boat is a Blue Seas 36 at 12 tonnes. Any thoughts? Has anyone done this?
Duke, I had to search to find West Lakes Shore.
What hp is the Yanmar, is it enough? Some Blue Seas of Lehman era came with twins, others like yours with a single.Problem in changing engines is not so much a different engine but all the hassle that goes with it, like electrical,changed engine mountings,prop shaft length,exhaust system.....have you given up on rebuilding the Lehman? Or finding another one? Or fitting a 135 which might drop right in? If I could make good the existing I don`t think I`d contemplate the swap.
The OP is in Australia, whole engine import is an expensive option. I got a new FW pump came from Wagga Wagga Tractor in NSW,it fitted a long list of trucks, tractors etc, I`d say the Ford parts are available.Marinizing parts could be imported from the usual suspects, ADC, Bomac, fredwarner1,etc.Have you contacted American Diesel.
http://americandieselcorp.com/
They offered a drop in replacement. Maybe they still do. It was a different engine but the power characteristics were similar.
They marinized the original Lehmans so they knew what it would need to be a drop in....
Near identical SD hull to an IG36.I am not familiar with the Blue Seas boat. Is it a semi displacement hull?
I am looking at purchasing the Blue Seas 36. It has sat idle for 6 years and needs a lot of work. The engine which was running fine when last used will not now turn over. The mechanic believes water maay have found its way into the cylinders. Unfortunately we will not know what is wrong until it is pulled apart which is why I am looking at all options. I will not make an offer on the boat until I am well aware of what it may cost repair and repaint the boat. A Blue Seas 36 is a Europa style displacement trawler built in Taiwan in 1982.I am not familiar with the Blue Seas boat. Is it a semi displacement hull? Second, you don’t say why the Lehman needs rebuilding. Are you absolutely sure it needs rebuilding? If it does, I would be very hesitant to put a lightweight high RPM engine in place of a heavy slow turning engine. You have been quoted $30k for the replacement. Is that price guaranteed or is it an estimate? If it is an estimate then be prepared for the price to escalate once the mechanic gets into it. The tranny, engine mounts, exhaust and a lot of electrical need to be changed. A couple of missed items in the estimate or something that goes badly and you can kiss the estimate goodbye. And in the end are you absolutely sure the lightweight high RPM engine will perform the way you want and need it to? How did the boat perform with the Lehman? Personally I would rebuild the Lehman and it will run for the rest of our lives if you take care of it.
The Yanmar is 4cylinder 110hp. Our diesel mechanic has quoted approx $20,000 to overhaul the Ford Lehman or approx S30,000 to install a new Yanmar and gearbox. New price 18,000 plus 12,000 for the changes. This is Australian dollars. I am wondering whether a 4 cylinder higher revving modern 110hp motor will be better than the old 6 cylinder 120hp slow revving motor and if anyone has experience with making such a change.
I am thinking of replacing a Ford Lehman 120 with a Yanmat 4jH110 common rail Diesel engine. The boat is a Blue Seas 36 at 12 tonnes. Any thoughts? Has anyone done this?
I have that Yanmar 110hp in my boat. It pushes it at about 7 knots at a comfortable RPM of 2000, but I have a pretty slippery sailboat type hull. It will push my boat 8 knots but that’s way too noisy for me at 3000 rpm.
My boat also weighs about 12 tons and has a waterline of 35’.
I don’t think you would be happy with the 110HP Yanmar. I would rather have a lower reviving, bigger displacement engine in a boat that size.
Dan,the OP reports that the engine is seized, and the boat unused for 6 years. It is "broke".Why replace it? If it aint broke, keep the money in your wallet.
Dude,
Is that the 3000rpm JH or the 3800rpm engine?