i have a 454 mark iv that i have to get out of a boat. the boat is up on blocks in the backyard, and getting a trailer back there is out of the question. i need to know how tall this motor is from the bottom of the pan, to the top. motor is stock. the arm on my engine hoist extends about 7 feet high. the highest point on the back of the boat is around 5 feet. i dont think i have enough clearance to get the motor out. also, is it possible to put the engine jack up on 6x6 posts, that would act like rails. this way the jack would be higher up in the air, but i would still be able to roll the jack out, once i clear the back of the boat.

based on your description...it's impossible. If the engine hoist is extended to 7 ft, that is probably at the 500lbs setting. How about a local crane/wrecker. They could boom the thing right over the front of the boat and set it one the ground pretty easily.

the boat is way in the backyard, and was placed there by a crane on a barge. he wont pull the motor. something about a disaster a few years ago with a swaying motor knocking a boat off the blocks. i am not about to tear the yard and bushes up to get this out. my only other option would be to have the crane put it back in the water, tow it to a ramp etc etc. i might just have the crane reset the boat lower on the blocks.

The boat can be lowered WITHOUT a crane, (we are talking a 24 footer, correct?)

Regular boat stands, jack it up, remove blocks, lower it down,......done.

It takes a whole lot of height (from the ground) to get a big block pulled. We just did my two, boat sitting on trailer. If I had to guess, the forks were 10' (or better) off the ground to clear the boat.

find somebody with a tow truck and use the boom, or a backhoe if you know someone..Rob

Just did this on my 25 Checkmate. If it is on a trailer you will need all of 11 feet of lift to get it out. This assumes you are using pretty short
Chains connected to the block as a sling.

lift it up as far as you can and build a platform to set it on . then reset chains and pull it out. dont put lift on any planks. you still may have to lower boat.