Cracked or should i say hole in block

Joined
Mar 24, 2003
Messages
64
hello all again. . heres the refresher. . .4.3L merc 1991 . . pulled it last weekend and tore it down. . found my problem, it seems that there is a crack or should i say a hole in the block on the side wall between the manifold passage and the upper half of the block. . here is my question now. . it is very easy to reack and the piece that broke off is sitting right next to it. . is there a way to weld this or is the block ready for the trash? any help or suggestions please. . everything else seems to be in fine working order.<br /><br />thanks Erik
 
Joined
Mar 24, 2003
Messages
64
Re: Cracked or should i say hole in block

Also, if this block is toast. . how much is too much for a new or rema block. . . .
 

ooootis

Petty Officer 3rd Class
Joined
Apr 26, 2003
Messages
80
Re: Cracked or should i say hole in block

well for the most part its trashed. Welding cast iron takes a lot of practice, it has to be preheated and welded with a nichel rod. If its just a crack it can be repaired with a weld or a cold plug but most likely u have fractures that cant be seen. If u are running fresh water system I would not hesitate too much to purchase a remanned engine if not better to go with a new long block.
 
Joined
Mar 24, 2003
Messages
64
Re: Cracked or should i say hole in block

ok. . i have been looking for replacement blocks. . and am not finding any that are reasonable. . 2 so far longs blocks for 1500 and one for 1900. . this seems overpriced. . any help out there. . <br /><br />also. . lets say i am going to get one of these. . what would the harm be in cold welding the crack or some sort of epoxy just to see if it will last. . other than a day to pull that POS again who really cares if it fails? am i correst in this. . I mean if it saves me a bunch of money and lasts a while. . i dont see the harm in trying? Any thoughts??????
 

mlslocks

Seaman Apprentice
Joined
Mar 30, 2003
Messages
49
Re: Cracked or should i say hole in block

I got through two seasons with JB Weld on a cracked 2.5 block before I found a 3.0 block I could afford. You might be taking more of a chance with a hole. Just make sure your bilge pump works good.
 

flashback

Captain
Joined
Jun 28, 2002
Messages
3,987
Re: Cracked or should i say hole in block

Did you figure out what caused the hole?
 

ooootis

Petty Officer 3rd Class
Joined
Apr 26, 2003
Messages
80
Re: Cracked or should i say hole in block

HMMMM u said here is a refresher. what was your problem to start with? and how large is the hole? <br />is there water intrusion?? do u ahve to chunk that is missing ???
 

kenimpzoom

Rear Admiral
Joined
Jul 13, 2002
Messages
4,807
Re: Cracked or should i say hole in block

If the hole isnt too big, perhaps you could drill it to a perfect hole, tap it, and put a plug in it, but cast iron is very brittle.<br /><br />Ken
 
Joined
Mar 24, 2003
Messages
64
Re: Cracked or should i say hole in block

water did mix with the oil yes. . but only for about 2 mins when i noticed when i was cheging oil this past month. . the hole soesnt seem to be caused by anyhting internal. . i dont seem to have thrown a rod and the hole is less then the size of a quarter. . the piece is intact that came out of it. . so what do you think. . cold weld it. . put a lil jb on it. . and run her til she dies :)
 

Yepblaze

Lieutenant Commander
Joined
Jun 1, 2001
Messages
1,686
Re: Cracked or should i say hole in block

Just by doing a Google search for 4.3 long block marine That $2K might be considered about right considering you don't have a core anymore.
 

ooootis

Petty Officer 3rd Class
Joined
Apr 26, 2003
Messages
80
Re: Cracked or should i say hole in block

cold weld is a term for a cast iron plug if u will. installation is supported by drilling holes, tapping with a very special tap (its tapered)<br />the plug is then inserted with a driver usually a tap handle or square drive socket.At a predetermined torque it breaks off (the driver portion) then another plug is inseted at 1/2 the diameter of the first plug plug. correctly installed they interlace. Welding with nickel is the better option or paste it in with JB weld.<br />Either way i would not reassembly with out first pressure testing the repair
 

anesthes

Petty Officer 2nd Class
Joined
May 5, 2003
Messages
186
Re: Cracked or should i say hole in block

Those 4.3 blocks are soo common its not even funny.. You should be able to get one out of a junkyard, local swap paper, etc. <br /><br />You should prolly be able to get a running block for under $500.00. Put the marine cam + intake on, accessories, and get back in the water.<br /><br />_OR_ you can get a long block from autozone, pep boys, etc, for _well_ under $2,000.00...<br /><br />-- Joe
 
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