Cracked Block

KirkDarch

Cadet
Joined
Aug 10, 2011
Messages
17
So the marina informed me that the Block is cracked on my 5.0L MPI engine, due to ?winterization issues?.

I have checked the archives and there is a lot of information out there on JB Welding the block etc? But if you want it done right it appears most people agree that the block should be replaced. A few questions I have, what is the difference between the Short Block and the Long Block, and what are the advantages of replacing one over the other?

Is there anything else I should make sure they replace or check when they are doing the repairs? Note the Marina is very small and they have a part time mechanic that will be doing the work (they are paying for the repairs, due to the fact that they were paid to winterize and store the boat). Since the marina is small and they are paying for the repairs themselves they obviously want to do things as inexpensively as possible.

Any suggestions / advice is very much appreciated.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,758
Re: Cracked Block

A short block is the engine block with its internals (no cylinder heads). A long block is the complete engine minus external accessories. On a short block you would use your existing heads. Nothing wrong with that provided you "know" they are in good shape but since they off the engine, it would be wise to have a valve job done on them as you will never have a better chance. That said, the extra cost will cut into the difference in cost between the short and long block which would have new/remanufactured heads. In your case, I would opt for the long block. If on a strict budget and you are a risk taker, go for the short block with no head work. Risk is high in that scenario since freezing was an issue. Lastly, since this shop failed at properly winterizing the engine, what do you think the chances are of having a trouble-free engine replacement by the same shop? I understand the shops responsibility in this issue.
 

RogersJetboat454

Commander
Joined
Jul 9, 2010
Messages
2,964
Re: Cracked Block

Short block = block with rotating assembly (pistons, rods, and crank).
Long block = Components of short block, plus heads, valve train. Most or all covers. More or less just require installation of exhaust, intake, and ancillary bits.

Insist on a long block. If the block cracked, there is a good chance that the heads may have cracked as well since they share the same cooling passages. Same goes for the intake manifold. Exhaust may be an issue as well if they did not drain it completely, or it's tired (needed replacing anyway).
 

tpenfield

Moderator
Staff member
Joined
Jul 18, 2011
Messages
17,624
Re: Cracked Block

I would have them go the longblock route due to the fact that there was freezing damage to the previous engine. As stated the long block will come complete with cylinder heads. the old cylinder heads could have sustained some damage on the old engine and you would not really want to risk having them brought over to the 'new' engine (if you did the short block). For the added cost, the marina/shop, could re-sell your old cylinder heads, if they determined that they were OK.

There will also be a labor savings to the shop in going the longblock route versus the short block.

So, it is 3-0 in favor of the longblock.
 
Top