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
- Start date
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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.
