Worst case situation, but how is a 36' GB Classic repowered with two Lehman 120's as the engines are larger than any access (out of boat entirely). Clearly this has been done many times. Would also be interested in opinions in repowering with newer designed engines.
How does one remove and replace two Ford Lehman 120's from a 36 foot Grand Banks Classic.
- Thread starter dullrich
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Comodave
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First why repower from the Lehmans? They are old but they are extremely reliable. Parts are available. But if you do decide to repower then you will likely have to strip the engine down to the block and take them out the door or window. But you will find that the repower cost will probably be more than the boat is worth. I would just spend a few thousand and go through the engines and replace anything that needs it. They do have issues with the number 6 cylinder overheating.
Mainship Pilot
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Drop some C18's in there, that thing will fly! 
Lepke
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Years ago I rebuilt twin Lehmans in a GB. As Comodave says. to get them out you have to strip them down to a long block. Usually you build a temporary gallows to lift them thru the floor. I had a utility vessel with a long arm that could reach thru the back. Did it in the water.
If you have light blowby, new rings and a light honing of the cylinders will fix it for a long time. Do a valve job, put in new bearings and seals and be done for 5-10 years.
Depending on your location, there are rebuilders that will do it in the boat using a boring bar to cut oversize cylinders.
Rebuilding is always cheaper that replacing.
If you have light blowby, new rings and a light honing of the cylinders will fix it for a long time. Do a valve job, put in new bearings and seals and be done for 5-10 years.
Depending on your location, there are rebuilders that will do it in the boat using a boring bar to cut oversize cylinders.
Rebuilding is always cheaper that replacing.
rgano
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Not sure of the door width difference, if any, between GB 36 and 42, but I had a Lehman 120 lifted into the saloon, placed on plywood overlaid on the deck and stripped to a short block before being lifted through the port side door (many GB36s don't have a port side door) from the pier by a long-armed forklift.
SteveK
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The GB36 without a port side door cannot pass the engine through the SB door as the wheel and dash are in the way. (at least the early ones).
I had previously read a thread, not sure if here or the old GB site where a monorail was built and they went out the back stateroom door. It still required making the engine skinny.
I had previously read a thread, not sure if here or the old GB site where a monorail was built and they went out the back stateroom door. It still required making the engine skinny.
What year is your GB? I have a 1973 glass hull 36CL. Our over head in the main salon has what looks to be a “removable” piece and I was told it was used to pull the engines out prior to me owning the boat. There is no seem on the fly bridge. But it is pretty clear that it is a separate piece when looking above the head liner. I have also seen them come through a window stripped down and pulling glass and frames off.
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Mambo42
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Why would you want to change 2 outstanding engines with something more modern ? FL 120's can last for 25.000 - 30.000 hours if you treat them well. That means change oil and filters on a regular basis, change the coolers on a regular basis and make sure you run on clean fuel. You should have no problems with them at all.
