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Is this rb26 block useable for modest build?

hixzoomy
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hixzoomy Apprentice

hixzoomy

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Posted

Hey Sau,

Long time lurker. I just wanted some opinions from the experienced guys to see if this block is still useable or if it's a boat anchor and I should try get my money back? My concern is this crack between the water jackets to the head bolt thread between cylinder 3 and 4 see picture attached. Little back story about it, I bought it as the start of a small build to put into my daily. Was told was running fine no issues the previous owner had just pulled it down to go forged bottom end lost motivation and was now selling if off, after I started to clean it up I found the crack. The target I'm aiming for would be between 375 - 450kw so not the biggest power output but as it's going into my daily ( probably in the year 2050 at this rate) I'd like to give it a chance at surviving for as long as possible. 

crack in deck rb26.PNG

GTSBoy Grand Master

GTSBoy

Posted
Posted

As far as I know the spot that breaks most commonly is on the exhaust side, adjacent to #4 or between 4/5. So any unnecessary weakness on the exhaust side, even if it's not is the "usual" spot, can't be a good thing. And between 3 & 4 is not so far away from where the block likes to jump to pieces.

hixzoomy Apprentice

hixzoomy

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Thanks for replying so quickly and sharing your knowledge. I had heard of the block issues between cylinder 3 and 4 splitting and the crack on the outside of the block from block twist after a healthy amount of power put through them but this is all new to me. When I spotted it I thought it might be a drama but was hoping it was more superficial so I could finish making the deck flat give it a hone and get down to ordering some parts, looks like I might have to start getting in touch with the seller to try get my cash back. 

BrynDETT Community Regular

BrynDETT

Posted
Posted (edited)

Mine has a crack from water gallery to headstud hole in-between 5&6... Sent it back together, been a year so far at 520kw and had no dramas yet .. I guess it all depends if you are prepared to do all that work to potentially do it all again 🤣

Edited by BrynDETT
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