damaged connecting rod (on post #11, can I use it or get another rod ???)
#1
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I took the pistons out from the short block Im using to replace the broken engine for my 88 S4. a few of the pistons have the coating gone. this one was the worst one (pics are from both sides):
Last edited by namasgt; 05-26-2009 at 04:40 PM.
#3
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FWIW, here are a set of '91 GT pistons that I pulled and Chemdipped them. After these pics I had Greg ultrasonically clean them to get the rest of the carbon off them. Though they look a little scary to my untrained eye, he said the coating on these skirts is just fine:
I am utterly unqualified to comment on this, other than what I've been told.
![](https://webfiles.uci.edu/redwards/public/All%20pistons%20short%20skirt%20side%20%231.jpg)
![](https://webfiles.uci.edu/redwards/public/All%20pistons%20long%20skirt%20side%20%231.jpg)
I am utterly unqualified to comment on this, other than what I've been told.
![](https://webfiles.uci.edu/redwards/public/All%20pistons%20short%20skirt%20side%20%231.jpg)
![](https://webfiles.uci.edu/redwards/public/All%20pistons%20long%20skirt%20side%20%231.jpg)
![](https://webfiles.uci.edu/redwards/public/pistons%20pair%20skirts%20with%20patterning%20closeup.jpg)
#4
Three Wheelin'
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Thanks for the pictures Rob, they do look like mine. I was also told to use chem tool (berry man). I also did read on an old post that someone sujested paint tinner.
I do have the old engine with the cracked cylinder wall on #8, if these look bad after cleaning I will take the other engine apart.
Thanks
I do have the old engine with the cracked cylinder wall on #8, if these look bad after cleaning I will take the other engine apart.
Thanks
#6
Three Wheelin'
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I just finished cleaning the pistons with berry man and have noticed some discoloration spots on the piston tops like bluish purple 2 or 3 of them have this and for one of them the piston pin has blue spots on one of the faces (I did not seperate the rods from the pistons).
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#8
Three Wheelin'
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on pic #1 the pin has turned blue
#2 & 3 are the same piston , the surface has dimples (there is another piston in the same state but with less damage)
#4 blue spot on the corner (is this normal or did the chamber got too hot using wrong spark plugs)
does any one know if any of these are bad.
Thanks
#2 & 3 are the same piston , the surface has dimples (there is another piston in the same state but with less damage)
#4 blue spot on the corner (is this normal or did the chamber got too hot using wrong spark plugs)
does any one know if any of these are bad.
Thanks
#9
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The sides are fine. Those pits, on the top, are from the engine sitting with moisture getting into the engine (exhaust valves open). The moisture turns the carbon acidic and attacks the surface. I'd guess that pin got that way when it was ground originally.
Clean, assemble.
Clean, assemble.
#10
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The sides are fine. Those pits, on the top, are from the engine sitting with moisture getting into the engine (exhaust valves open). The moisture turns the carbon acidic and attacks the surface. I'd guess that pin got that way when it was ground originally.
Clean, assemble.
Clean, assemble.
#12
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I am going to defer to Greg Brown on that, but from what I see (you need a Macro lens
) that is nothing a sheet of glass and a very little 2000 sandpaper will not fix.
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#13
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I can actually feel it with my nail.
it happened by the drill hitting it while I was trying to remove a rust spot on the rod using a nylon brush, but then the drill slipt from my hand and the chuck hit it.
#14
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I'll give you a rod if you're concerned. I don't think that damage would propagate a crack, but stranger things have happened. PM me if you need it.