I just purchased a boat that has a cracked block and locked up mud buddy 5000. He said they were driving it flat out and Iit made a horrid sound and just locked up. He took it to a mechanic and they told him the block was cracked and probably a bent rod. I haven't had experience with blown engines as I haven't blown one up yet. But I know these Briggs are notorious for it if modded.

Do I scrap that setup all together? Go the replacement shortblock route? Or buy a new 40 horse EFI and repower with that?

What route would you guys suggest going? This one has a new mikuni carburetor on it and a new BPS muffler. So I guess I wouldn't be starting from scratch with a new short block but is that just going to crack 100 hours down the road to? I read somewhere that the new 40 horse Briggs blocks are supposedly a little stronger, not sure if that's true or if it's just hype. Any input from you guys would be great. Thanks

If I had what you had, I would go with a short block and use your current mods on it. A lot of block cracking has to do with running an unbalanced 2 blade prop. Even the balanced 2 blades vibrate a lot more over the three blades, but it depends on what you want. Personally, I would build a short block with the mods you have and go from there bro

The block cracking in this case likely had nothing to do with the prop. When it makes a nasty noise and locks up, its typically gonna be one of those internal pieces running into something it wasn't supposed to. And it wont be a bent connecting rod. Itll be broken, or the piston will, most likely. Running it at max rpms without solving the rotating ENGINE assembly balance issues causes things like that. A cracked block cause oil leakage and engine seizing from that, or head cracks because of the extra weight of the exhaust with the prop vibration, but typically isnt bad enough from an out of balance prop to cause internal damage (ie rods breaking, etc).

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I can't seem to find specs on the mud buddy 5000 sport. Do they have upgraded iron mountain heads like black deaths? Gonna need some grunt pushing a loaded 1854 gator Trax in the skinny sand bar infrsted River we run.

To the OP: you gotta make that call. D you want the power that 5500 had? Do you want efi? Do you want to turn the wrenches yourself? Etc. There are a few questions to answer for yourself to help you decide. I like carbed engines, because I dont particularly want to have to wait on sensors, special wiring harnesses, and an extra fuel pump (theres a low and high pressure on the efi engines) to come in the mail if something happens to one of those items while I'm on the water. I just pull out wire, or pull apart the carb, and other than starters dying randomly, I have run into any issues that couldn't be handled fairly simply. That being said, the failure rate of those items doesnt seem to be common on the 40, so it's probably as good of an option unless you want that extra power on the rebuild.

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Pretty sure the 5000 only had heads, exhaust, carb and cam, but don't know. Will c or Marcus probably knows.

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I am a carb man myself and would prefer that over efi for simplicity of it. But if the rotating assembly is shot and chances are it could have taken a head if the rod snapped then I am back to just a stock shortblock with muffler and carb. Does anyone sell a shortblock with im or worked heads?

Usually the cracked blocks are from still running a gasket between the rear cover and block. They should be updated to a wet gasket at first signs of a leak. All new built engines and new engines are set up wet. This solves most bock cracking. I recently had an old 5000 in here. During tear down I was expecting a built bottom end like a mag45. This one was a stock shortblock with heads carb exhaust. Boat and block are an 09 and the bps heads were actually pretty clean. I don’t know if this is the same as all other 5000’s but that’s 1

Who sells good worked heads that I could add to shortblock and then put the other mods back on it.

I want a reliable plant but I would also like to be able to run close to 30 mph with the boat and a light load. Guessing it will take at least 45 horse and a good prop to do that with this boat. So any input on mods I could do now to get it where it needs to be would be appreciated. I am guessing decked heads, maybe a little more cam?
?

You should pull and inspect your heads. Cheaper to rework a set than to buy new ones plus build them. Your plan to grab a shortblock and put your stuff on it is the simplest way to do it and makes a good motor. If I can help just holler