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2018 zr2 ccsb duramax
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Yea I have no idea at what temp the limits are set. I basically just have the one temp sensor left on my egr.
 

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Lightning98,

Are you still breaking the engine engine now? I wanted to inquire a little more about your aftermarket pistons and oil squirters. Mahle made the custom pistons correct? Was there an arrow on the pistons indicating orientation in the bore? I am wondering if the pistons were installed 180 degrees out? The oil squirters are designed to shoot oil up into a little hole on underside of the piston into a hollow cavity and then flow out the cavity on other side of piston. If the squirters needed to be re aligned to clear the piston skirt, they are most likely not lined up correctly to spray into the hole on bottom of the piston. This will lead to piston swelling when under load for a long time. Look on the underside of the stock pistons to reference how small the holes are for the oil spray. The spray angle for the oil squirters was completed in CAD to ensure the proper orientation. It would be a pain, but putting some straight wire in one of the oil squirter holes pointed upward you could get a new alignment as to the exact location the oil jet will be spraying.
 

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2018 zr2 ccsb duramax
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the pictures of the pistons on the first page of this amazing journey show an arrow etched onto the top of the piston. As to how he oriented them in the bore only he would know. Also it looks as though the aftermarket pistons dont have the same cooling ports as the stock units. Could be there and I'm just not seeing them..
 

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2021 Colorado 2.8L Diesel Z71
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523 Posts
Photos on the first page do show a lack of cooling ports on the aftermarket pistons.
Posts 155 to 157 show the ports on the stock piston and offer a bit of discussion on the differences.
Post 185 shows the aftermarket pistons correctly oriented in the block.
Yeah, I now recall that I was the one who pointed out that the OP's pistons do not appear to be designed for use with piston cooling jets. I wonder if that is, indeed, why they hit the jet and broke it off.

It's kind of puzzling to me. My experience is only HD diesel, which universally have PCJs and also pretty much always have a 'cocktail shaker' chamber in the piston. The PCJ's fill the 'shaker' channel under the bowl rim at BDC, and then the oil slops around in there on the next two strokes to pull heat from the bowl while dripping back out of the fill hole. And PCJ equipped cooling piston engines also usually count on that flow to lubricate the piston pin as well.

OP's pistons really do not look like they were designed to use PCJs. I've not seen everything yet, but I've not seen an OEM engine where PCJs were directed to just wash across the bottom of a piston like that.
 

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Yeah, I now recall that I was the one who pointed out that the OP's pistons do not appear to be designed for use with piston cooling jets. I wonder if that is, indeed, why they hit the jet and broke it off.

It's kind of puzzling to me. My experience is only HD diesel, which universally have PCJs and also pretty much always have a 'cocktail shaker' chamber in the piston. The PCJ's fill the 'shaker' channel under the bowl rim at BDC, and then the oil slops around in there on the next two strokes to pull heat from the bowl while dripping back out of the fill hole. And PCJ equipped cooling piston engines also usually count on that flow to lubricate the piston pin as well.

OP's pistons really do not look like they were designed to use PCJs. I've not seen everything yet, but I've not seen an OEM engine where PCJs were directed to just wash across the bottom of a piston like that.
Scott with Screaming Diesel Performance Custom orders them with their supplied specifications.
Maybe SDP didn't specify them in their custom order ?
 

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2018 ZR2 Duramax
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160 Posts
Discussion Starter · #347 ·
There is piston squirter cut outs in the skirt, they just need to be moved over half an inch and they would be in the perfect spot. Pretty sure it’s an error on specifications Mahle
was given for these custom pistons.

But even with squirter cut out error, the tip of the piston squirter’s comes in contact with the piston right under/off to the side of wrist pin.

And as others have noticed there is no cocktail shaker style opening for the all squirter‘s to shoot into. All I could do was shorten and bend them so I could shoot the oil towards the hole in the bottom of the piston.

And some have mentioned maybe they was meant to be used without oil squirters. I highly doubt that since some old diesels use to not have squirters but pistons would melt if EGTs were above 1300° for prolonged times. And also the fact there is a piston squirter cut out pretty much debunks that theory lol.
 

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The price of breaking new ground and going where few if anyone have gone before I suppose! What an interesting read this has all been.

It is all also well over my shade tree casual mechanic pay grade :LOL:
 

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The pistons lighting have could be early designs. The rights to that piston from Mahle is SoCalDesiel they designed them. I know there are a few designs by them they made a custom set for me with some modifications with valve pockets and ring landings and style of rings it will except that I requested But pistons were made to run the squirters
 

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2018 zr2 ccsb duramax
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Any time on the dyno coming up ?? Hp tq numbers??
 

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2018 zr2 ccsb duramax
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Is the May ROTM still running strong ?? Or did something go awry ?
 

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If I wasn’t subject to going back to SDP for a built transmission or possible future engine parts I would’ve definitely complained more. But I don’t want to bite the hand that feeds me in case I need something custom built later on lol.
I'm going through withdrawals from the lack of updates. Hoping you have just been busy and haven't encountered problems!
 

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I hope there wasn't a major problem :(
 

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He was having problems with his pistons, hope there wasn't major damage and he gave up on it :(
 

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Silence is sometimes the best incentive for issue resolution. I expect he'll post status when all is well.
Been alot of silence :(
 
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