Mahle Pistons

[icanfixall]

I talked to the tech dept. today at Mahle about my 1441800WR STD hard anodized top pistons being as much as 52 thousands up out of the block. If I mill 25 thousands off the top of them the top ring will be seeing much more pounding from the compression and the piston bowls will be very differant causing the motor to probably run differantly. I would have to adjust my fuel to counteract this possible problem. Thats not a problem but the increased pounding on the top ring bothers me some. They can supply a low compression piston that has the same hard anodized top (144181). What they do is mill the pin location higher in the piston instead of reducing the dome thickness that around 580 thousands if anybody needed to know. I'l bet some of you are asking why are my pistons so high up out of the block??? So am I. I know when the sleeves were installed the deck was milled because I wanted that done to level out the block to the crank that was already line honed. Then when it lost a freeze plug one sleeve seemed to slip down into the block. I know not a good sign either but I had the deck "cleaned up" so I feel thats where the tall demensions are coming from. Plus when I originally assembled the motor I had pistons from 38 to 46 thousands up out of the block. But it ran well at those demensions. What to do now has me really looking at it hard now. Maybe just start over with my spare block and move forwards. I don't know yet....

 

[towcat]

gary-
I would be asking myself one question. Do I really believe in the machine shop who put in the sleeves? The question is not in the form of ethics or morals but rather if I feel their work is trully competent or not. If you have the slightest doubt, then its time to start fresh with the second block with a machine shop you can trust. Pistons can be "dialed in"...but metal removed can never be "returned"

 

[tonkadoctor]

As much metal as you have had taken away from the deck you may have problems installing the intake manifold too unless it has been machined to match. A ****** block will eliminate much of the fight you are going through.

If you do retain this block then I vote for relocating the wristpins as the correct way to move the pistons lower in the bore vs milling the tops.

 

[icanfixall]

Well, order has been placed for a set of Mahle reduced compression pistons (144181stdha tops) The pin is machined 10 thousands higher in the piston to lower the piston in the stroke but retain the crown thickness of about 580 thousands. Now if it still is too high up out of the block I'll machine an additional amount off the top and ceramic coat it. Machining the pin bore in the rods will only give me about 6 thousands more drop on the piston. Thats not nearly enough for the work involved. If my block is usable after all the milling to it I'll be up and running sometime in May... I hope. Otherwise I just sleeve the spare block but use another machine shop time time. Trying to find a competent machine shop will be the next big deal. Burn me once shame on you. Burn me twice shame on me.....

 

[icanfixall]

WOW..... I just called ANDtalked to chris at diesel direct. My 2 missing pistons were overnited to me and will be here tomorrow morning..... Should I get excited yet???

 

[tonkadoctor]

WOW..... I just called ANDtalked to chris at diesel direct. My 2 missing pistons were overnited to me and will be here tomorrow morning..... Should I get excited yet???

I'd only get excited if they show uo tomorrow with their track record. Got my fingers and toes crossed fer ya.

 

[icanfixall]

Today I called Cometic, Atomic (Nick Araias) and SCE Gaskets about building up some head gaskets that were 90 thousands thick. My Felpro are 75 thousands thick. Nobody can or will make up a set. At SCE they can make up a set of dead soft copper or something else with a stainless steel wire sandwiched between the copper but that wont work with all the warmup and cool down cycles that a daily driver gets. So for those of you that feel head gaskets can be made up for our motors is not correct. At SCE they told me that some high pro builders are having some luck with using a standard gasket and their copper shim gaskets but seperating the standard head gasket and adding that below the shim. They said it has been working but I can't see using this on a daily driver with all the heat cycles that we do.

 

[Diesel JD]

So...head gaskets cannot be made for a 6.9/7.3 or hi performance head gaskets are not suitable for a DD? It would seem you could still make standard ones...which to me is much more of a concern as these vehicles continue to age and fewer people make parts for them.

 

[icanfixall]

Its not that these gasket makers can't fab up some head gaskets. Its they wont because there isn't enough demand for any. Felpro will probably always be making them as will International.

 

[RLDSL]

Today I called Cometic, Atomic (Nick Araias) and SCE Gaskets about building up some head gaskets that were 90 thousands thick. My Felpro are 75 thousands thick. Nobody can or will make up a set. At SCE they can make up a set of dead soft copper or something else with a stainless steel wire sandwiched between the copper but that wont work with all the warmup and cool down cycles that a daily driver gets. So for those of you that feel head gaskets can be made up for our motors is not correct. At SCE they told me that some high pro builders are having some luck with using a standard gasket and their copper shim gaskets but seperating the standard head gasket and adding that below the shim. They said it has been working but I can't see using this on a daily driver with all the heat cycles that we do.

Could they not make up a set of multi layer steel head gaskets? The advertising says they can make them up to .120 . You would need a very smooth finish on your block and heads for that type gasket though, maybey that's why they didn't mention it

-------Robert

 

[icanfixall]

Well, I went out to lunch with family today and when I got home there was a box waiting for me. It was huge and from Mahle in Tenn... Go figure. Inside I found 2 pistons just the right size and type.... Much better than the 2 that diesel direct had forgotton to ship to me when they shipped my OTHER 6.... They even are the correct weight now too. So,,,,, after many tense moments waiting for something I finally have it. But its too little too late now. I went out and bought a 2007 PSD. The heck with it.......... You know, I'm sitting here looking at what I just typed in here and it seems so bad to do this. Its not the truth at all. I know I can afford a new truck but it will never be a dodge, chevy or ford. It will only be a Freightliner Sportschassie and thats all it will be...... Anyway Wednesday I pick up my set of low comp Mahle pistons and I'll test fit them. And if needed I'll mill off the hard anodized tops and them ceramic coat them and run those after I have "things" balanced. I've checked my first balance shot and I feel these pistons I have now would be ok without running them thru a balance shot but I'm not using them. I hope my second set of Mahle pistons are close to the balance weight from piston to piston in the set.