[Brenton Ruggles]

Good morning everyone, I very much apologize for the long hiatus on information. Between life and extra military training activities I’ve been preoccupied .

Truthfully I can’t even remember where we left off. Anyways got the truck running again and spent hours bending the old squirter‘s to the perfect location that nothing would interfere.

Broke the truck in and finally started driving it normal. I was headed to check some wells and while pulling a RZR going up a decent incline and was building I believe around 70 psi I blew a turbo boot, so I pulled off the road shut the truck off and duck taped the boot back together.

Started it back and noticed a knocking, long story short it spun a rod bearing, bent some valves, ruined that rod and heated the crank so probably ruined it and some other issues happened.

What I believed happened was when we built the motor, The bearings we received put the motor on the tight end of the normal range of what GM recommended. Well within the safe range, but like I said on the tighter end. I think from the extra power and the heat it was building, cooked the thin film of oil on the bearings and locked it up.

Hindsight definitely should’ve built the motor more loose, like wore out loose.

Put way too much money into this project trying to retain the Diesel. Anyways after a long hiatus of messing with the truck, about a month ago I picked back up and decided to swap a gen 5 L87 and 8L90 8 speed transmission into it.

Going to put an aggressive cam and the usual bolt one onto it but that’s about it. If you guys have any questions about the last build, ask away.

Or if you think there will be an interest for this new build, I’ll start another thread and document it.

I have a lot of interest in the Gen5 L87 and 8L90...My engine just nuked and I can find those engines all day. Hell do an EV swap at this point LOL

 

[rotaryenginepete]

I have a lot of interest in the Gen5 L87 and 8L90...My engine just nuked and I can find those engines all day. Hell do an EV swap at this point LOL

Might want to find a 2015-2018 Tahoe or Yukon donor, my 2018 Denali has the L86 paired with the 8L90. The only major difference between the two is that L86 has AFM while L87 has DFM. I am fairly sure that most if not all of the newer L87 applications are paired with the 10 speed.

 

[Lightning98]

Anyone who is interested in following the L87 swap here’s the link. Thanks!

Let’s swap a twin turbo diesel ZR2 over to gas.

Good evening everyone! Some of you are familiar with my previous built 2.8 duramax twin turbo build. https://www.coloradofans.com/threads/deleted-dmax-zr2-melted-piston-time-to-build.420559/#post-5441684 And if you did follow that build, then you know the unfortunate outcome of it. Anyways...

www.coloradofans.com

 

[yrkdmax]

Not too far-fetched that Mahle is making "aftermarket" pistons... considering that they make the stock pistons to begin with. Here's a new one to replace my holed piston in my original motor.

View attachment 403986 View attachment 403989

Note "MAHLE" is cast into inside of piston above pin to the right in first picture.

As for a previous question on steel or forged aluminum pistons. This one is aluminum, but note the steel or cast iron top ring land. Not sure if steel or cast iron, but definitely not aluminum.

Back from the dead, and to clarify the top ring landing on both the factory Mahle and the aftermarket Mahle pistons in this thread are all hard anodized.

This is not a steel or iron ring landing like we all had hoped.

 

[fjm568]

Back from the dead, and to clarify the top ring landing on both the factory Mahle and the aftermarket Mahle pistons in this thread are all hard anodized.

This is not a steel or iron ring landing like we all had hoped.

Bringing an old thread back...

Been away for a while...

Saw this and wanted to reply. After more investigating, I do agree that the top ring land is not steel or cast iron as it is not magnetic...BUT I believe it may be something other than anodized or hard anodized aluminum. Anodized or hard anodized aluminum is not electrically conductive...so I tested my piston's ring land with my ohmmeter and it went to zero, so it is still conductive. Don't know what the top ring land is, but it's non-magnetic and conductive.

Just some more info to this puzzle.

 

[rotaryenginepete]

Anodized or hard anodized aluminum is not electrically conductive.

Is it possible the pistons are coated with a dry-lubricant that is conductive?

 

[Yo momma]

Stainless steel top ring land?

 

[rotaryenginepete]

Stainless steel top ring land?

oh yeah I forgot hard stainless is non magnetic

 

[Yo momma]

I'd be curious to find out why it's not steel. My guess is the (potentially) stainless steel alloy has a similar coefficient of expansion compared to the aluminium alloy used in the piston.

 

[fjm568]

Is it possible the pistons are coated with a dry-lubricant that is conductive?

If you look at my post #155, the skirts are coated, the rest is machined.

That top ring land could very well be stainless. (Or maybe titanium or something) Some stainless could be very, very slightly magnetic and there did seem to be a little bit of pull there, but almost nothing.

Without having the old piston out of my blown motor, short of cutting it in half and seeing what it looks like inside, I couldn't say any more for sure what it is.

Story was in the old Buick 3.8L Grand National motors, the pistons they used in them were based on diesel pistons and they were said to have a steel plate cast into the piston top to increase the strength/survivability. They were very heavy pistons. I'm assuming that is still done on the newer factory stock diesel pistons in the industry.

 

[Yo momma]

... I'm assuming that is still done on the newer factory stock diesel pistons in the industry.

It is also common on modern turbocharged gasoline direct injection engines.

 

[NutzaQ]

Some stainless could be very, very slightly magnetic and there did seem to be a little bit of pull there, but almost nothing.

True stainless is not at all magnetic. Less than standard stainless (aka Made in China) will sometimes have the slight magnetic pull that you speak of. These same parts are prone to rust since they are not "good" stainless.

They just don't make them like they used to.

 

[Yo momma]

True stainless is not at all magnetic. Less than standard stainless (aka Made in China) will sometimes have the slight magnetic pull that you speak of. These same parts are prone to rust since they are not "good" stainless.

They just don't make them like they used to.

Stainless is a catch all phrase. Kind of like trees; there's a **** ton of different trees in the world. There is a wide variety of both magnetic and non-magnetic stainless. No need to get into the metallurgy here but Wikipedia will tell you all that you want to know and more.

 

[NutzaQ]

Stainless is a catch all phrase. Kind of like trees; there's a **** ton of different trees in the world. There is a wide variety of both magnetic and non-magnetic stainless. No need to get into the metallurgy here but Wikipedia will tell you all that you want to know and more.

This is misleading at best. Granted there are various types of stainless steel but it's hardly a "catch all phrase" as it is quite specific in definition.
And Wikipedia is a less than reputable source.

 

[Tom S.]

This is misleading at best. Granted there are various types of stainless steel but it's hardly a "catch all phrase" as it is quite specific in definition.
And Wikipedia is a less than reputable source.

You are both right. It is a catch all phrase for a class of steel that resists rust and corrosion. Some is magnetic and some is not, and some are actually resistant to rust but can under certain conditions still rust. There are also various machining capabilities to the various grades. I have had some that was used in the nuclear field that was downright miserable to try and drill or machine.

IIRC, stainless is made by adding nickel alloy to the steel and the amount added determines the ability to resist corrosion. But I am sure other alloys are compounded to make various other desirable properties. One less desirable property of common stainless is the tendency to gall under friction. Another is stainless typically has less strength than its plain steel counterpart.

 

[Yo momma]

This is misleading at best. Granted there are various types of stainless steel but it's hardly a "catch all phrase" as it is quite specific in definition.
And Wikipedia is a less than reputable source.

I've taken university level courses on metallurgy. Wikipedia has more than enough information on it to satisfy 99.9% of the population. It is more than accurate enough for it's intended audience.