Pitted piston

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binlicker
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Pitted piston

Post by binlicker » Fri Nov 16, 2018 10:51 am

Does this piston crown look knackered. The tracking is only superficial but I've marked a small indentation.
S0358389_LI.jpg
Pitted crown
S0358389_LI.jpg (143.78 KiB) Viewed 523 times
. Any clue what could have caused it. Steve



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Nick
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Pitted piston

Post by Nick » Fri Nov 16, 2018 11:09 am

What engine? Looks well knackered to me.


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Pitted piston

Post by Coupe Racing » Fri Nov 16, 2018 11:21 am

Scrap it


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David Tew
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Pitted piston

Post by David Tew » Fri Nov 16, 2018 11:23 am

Looks like corrosion to me. There seem to be two more crusty areas near the centre.

I think it's scrap as you can't really ascertain how deep the tracking and pitting are and they will definitely create weak spots.


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scimjim
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Pitted piston

Post by scimjim » Fri Nov 16, 2018 11:29 am

Very strange markings - has it been sat in water?


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Roger Pennington
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Pitted piston

Post by Roger Pennington » Fri Nov 16, 2018 12:08 pm

Presumably this is from the lean burn 1.6 cvh with the corroded bore?


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binlicker
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Pitted piston

Post by binlicker » Fri Nov 16, 2018 12:50 pm

Yes it's from the rust damaged bore, so yes again it's probably water damage from being sat unused for so long. Thanks for your help. Steve.



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Pitted piston

Post by reliant-reviver » Fri Nov 16, 2018 5:30 pm

Should have seen the state of the one that came out of an ex race engine of mine, was making 130bhp until the block got wrecked due to frost.

I would be tempted to dress that back and clean the crown.

Otherwise can I have it please? Got a set of turned down (for lower CR - turbocharging) lean burn pistons but one is knackered.


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Roger Pennington
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Pitted piston

Post by Roger Pennington » Fri Nov 16, 2018 6:01 pm

How badly rusted is the bore? Have you considered re-boring? As it looks as though you may need pistons anyway, then perhaps that might be worth considering, especially if the rest of the engine is in 34,000 mile condition, as your other post suggested?


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binlicker
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Pitted piston

Post by binlicker » Fri Nov 16, 2018 6:50 pm

I've changed tack slightly. I spoke to Jim earlier in the week and he was willing to supply me with a used engine block. When I examined number 2 piston I saw the pitting so decided I would get it re-bored and fit new pistons. I showed it to the engineer and he thought the damage in the bore might exceed the max of 1mm for a re bore so he suggested a liner keep the std other 3 pistons and buy 1 std piston to replace the pitted one. I will let him see the pitted piston on Mon to see if it can be saved. Steve



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Pitted piston

Post by gtcse8 » Fri Nov 16, 2018 7:26 pm

Phil if you do get the #3 piston from Steve and it needs skimming just ask.

Also, don`t forget the speedo that Reliant Partsworld are holding for you.

Nigel is back off holiday on Monday.

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binlicker
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Pitted piston

Post by binlicker » Fri Nov 16, 2018 11:17 pm

Yes reliant-reviver you can have the piston if it's not suitable for going back in the std engine. Steve



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