Cracked Piston thread

[tbsimmons]

What are the reasons do you guys think are the causes?
Heat, Timing, High Horsepower tunes, etc.
I am starting to get a little nervous now with the posts about pistons.
I usually dont get the truck much over 1000 EGT, run either the street or tow tune from IDP. I can get it higher but the max I have seen is in the 1200 range and was for a short time. Max boost was this past weekend at 48 towing the fiver. Usually in the 40-41 range on the tow tune.

 

[jdgleason]

I agree that the stockers aren't super robust, but I haven't seen or heard of a piston that has been either coated, or machined, let alone both, that has cracked. Seems like all of the pistons cracking or breaking have been completely stock. And even then, some trucks never have a problem...

 

[mike@haller's]

Has anyone cracked a piston after the bowl lip was machined?

Not that im aware of.

What percent of piston failure is on the #7 or #8 cylinders? Just curious if the back two are the ones most often cracking?

From what ive seen no. Ive seen them crack in every cylinder. If anything its mainly the middle cylinders that I have seen crack.

 

[B585Ford]

Not that im aware of.







From what ive seen no. Ive seen them crack in every cylinder. If anything its mainly the middle cylinders that I have seen crack.

Do you have an opinion on what seems to cause them (besides less than optimum design)?

 

[mike@haller's]

Do you have an opinion on what seems to cause them (besides less than optimum design)?

Not yet. I havent found one particular thing causing it. Other than the piston is just a poor design like sledpull stated.

 

[Jhaddox]

I agree that the stockers aren't super robust, but I haven't seen or heard of a piston that has been either coated, or machined, let alone both, that has cracked. Seems like all of the pistons cracking or breaking have been completely stock. And even then, some trucks never have a problem...

:whs:

I never had a problem with my pistons in my truck..Tuning wise, ran Innovative and Spartan. Heat: Maxed out the DashDaq plenty of times sledpulling and drag racing (1800+ deg.), ran anything from spartans 210 to the 350 file, ran all of Erics files....the engine had the piss beat out of it, and it was fine...then i hear of guys babying their trucks and have one break...its so hard to pinpoint whats making them do it, because when it happens the conditions arent the same between vehicles

Hell I even drove it 140 miles with the uppipe broken off the flange and the exhaust could never hit the turbo to spool it...basically a N/A diesel, it ran really hot the entire time, and had way to much fuel to even think about burning because of the turbo not being able to spool...when we tore it down my pistons were fine

 

[Wemoy1]

wow thanks for all the input I have alot to go off of now. I am going to take everything in on this and I may take the heads off to do the valve springs and I can look closely at it.

 

[NathannialD]

It's still possible as you will still have cast pistons. Cast is a more brittle form of aluminum. Soon we should have forged piston option for 6.4's

we have had some for quite some time.

 

[powerstrokin15]

I'm chiming in.



I'll just leave this here.





btw mine is piston #2

Sent looking at my blown up 6.4

 

[Matt]

we have had some for quite some time.

Details please?

 

[Strokin6.4]

32k 195ish oil temps and 196 coolant. No signs, even had heads off at 29k.
Number 8
Sent from my SCH-I535 using Tapatalk 2

 

[jdgleason]

Details please?

The forged pistons do require new rods. Pistons are Mahle forged and come with carillo rods.


https://www.elitedieselengineering.com/product/14020015/MahleCarrillo-Long-Rod-Kit/

 

[Matt]

Oooooh. I already have rods, so no go for me.

 

[08BIGRIG]

One thing that I have been wondering is, "What tuner and tune are the guys running that have had cracked pistions?"

 

[jdgleason]

One thing that I have been wondering is, "What tuner and tune are the guys running that have had cracked pistions?"

Take your pick lol

 

[Morgan@Midwest Diesel & Auto]

we have had some for quite some time.

I was unaware that your mahle pistons were forged instead of cast? I was under the assumption that they were the same pistons that mahle makes for navistar, only cut and coated.

My bad.

I was referring to forged factory replacement pistons that will use factory rod dimensions.

 

[powerstrokin15]

I've ran KEM 345 for like 20k Gearhead race for like 10k and idp race for prob 25k. SO take your pick. haha.


Sent looking at my blown up 6.4

 

[forcefed6.4ford]

If you haven't blown a piston you're not trying hard enough LOL

 

[jdgleason]

I was unaware that your mahle pistons were forged instead of cast? I was under the assumption that they were the same pistons that mahle makes for navistar, only cut and coated.

Both are available. However, the forged pistons are only available with rods. The international pistons you are talking about are still cast.

 

[powerstrokin15]

If you haven't blown a piston you're not trying hard enough LOL

this ^ cracked pistons or bust


Sent looking at my blown up 6.4