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towmein

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have a volvo penta 5.0/gm 305 the block is cracked i have an automobile 305 block i want to take everythiong out of the marine 305 and put it inthe other block, pistons, cam shaft, everthing but the gaskets what problems do i face
 
Your pistons will need to be in near pristine condition, as well as the bore in the replacement block.
The bore must be honed in order for the new rings to seat!
New rings/new bearings must be used.

If re-using the OEM Flat Tappet camshaft, all cam followers will need to be placed on the exact same cam. No exceptions!
If roller...... this is a non issue!

Many will recommend that you not re-use these components, and that you use all new.
Your call!
 
You'd be trading one set of problems for another. Your boat as it sits is virtually worthless and unsellable. With a car engine in it, it would still be worthless and unsellable. Who'd buy it? Oh, I see you wouldn't disclose that it has a car engine...hmmmm. A rebuilt marine long block 305 is about $1500. Installing it correctly will not only increase the value of your boat but will give you a warranty and peace of mind. Now you've invested a thousand or two and the boat has a new engine, making it far more attractive if you have to sell it.
 
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Well, hold on here, o2batsea! That was a very unfounded post..... and sarcastic to-boot!

All SBC Marine engine blocks are automobile engine blocks.
The internal components that towmein plans to use are from his freeze cracked OEM Marine engine!

The "Question" should be whether or not swapping used pistons and cam followers is advisible! I say NOT, but he certainly would not be the first person to have done this!

The engine block is not the issue once it is built to marine specs.
If the pistons were to mic out as in A-OK, and if the bore were to mic out as in A-OK, it may very well work just fine!
I'm not defending this procedure, but being the Devil's advocate, what's the difference if a set of pistons continue their life (let's say another 400 hours) in a different engine block that made bore specs?????

BTW, towmein, it is often cheaper to build a 5.7L than a 5.0L if you are buying a core anyway.
 
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thanks for taking time guys the wife says boat repairs don't fall in the budget so i'm checking inexpensive options to get back in the water its probably gonna be a summer on the sand or until i can steal enough from "our money" to do it right thanks again
 
My advice is sound and I stand behind it. I may not be an industry professional, but I'm no neophyte by a long ways. No kidding all SBC engines are automotive, what else would they be? Some castings are better than others though; not all chevy v8 blocks are suitable. OK by the time one locates a usable engine core, has it torn down, magnafluxed, and machined, buys new gaskets and bearings....plus having all his old stuff inspected cleaned and reconditioned do you really think it will be less money than a re manufactured long block? Really? Let's not even get into the issue of finding a machine shop that won't take MONTHS getting around to his project. Or screwing him either partially or completely...at which point he's back to square one and probably out some significant cash. The machine shops I have ever dealt with are not interested in piddly projects like a boat engines. They never clean parts to my satisfaction; always find rust or grime stuck somewhere. I think it's false economy to try to refurbish some random chevy v8. Who's going to stand behind it if it locks up in a month? Just saying.
I'm trying to save the guy a little heartache. There's more involved here than just money. I don't want him to miss the entire summer waiting. He can go whichever route he wishes, but in the end I think he'll be WAY ahead of the game to get the drop-in and be on the water instead of making phone calls to Billy Bob asking when his engine will be done. Been in that chair enough times myself.

and sarcastic to-boot!

You read it wrong my friend. No sarcasm either implied or intended. That's just my irascible personality shining brilliantly. Don't taze me.
 
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Sarcasm:
Who'd buy it? Oh, I see you wouldn't disclose that it has a car engine...hmmmm.
Click to expand...
I'm simply calling you on what I read... nothing more. They're your words, they do read as though sarcastically intended, and are not particularly constructive in helping Towmein with his question!
Look, let's NOT lock horns in Towmein's thread. I say, let's be contructive, and in a positive way as to help the guy!
Fair enough? :)


Towmein, while again I don't necessarily agree with what you are proposing, nor your approach to it......., perhaps the other gentleman is not understanding that you are wanting to do this on a "Shoe-String" budget!
I understood this from the get-go, and from your post # 1.

I'm old enough to know that this has been done many many times before, and if careful enough, can be made to work.
The only NEW pistons are still in the box and on the shelf! :D
However, you'd want to be very clean about it, and you'd want to make sure that the "donor" block's cylinder bores all size up correctly for the other pistons!
There will be a protocal to follow just as though building a freshly machined engine block.

Again, would I recommend this? :eek: NO, I certainly would NOT!
But it's your call/your boat/your engine!

Don't allow any Doom and Gloom attitude to prevent you from exploring this option.

Rick
 
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