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pentastar head problems?

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Old Aug 25, 2012 | 06:31 PM
  #101  
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Originally Posted by Four Low
So these are throw - away, non -serviceable heads. Great durability issue here.I wonder what thls engines life expectancy will be.

That depends on the maintenance and service of the Penastar, how well you take care of it, driving habits and the environment it's in.

This is just my opinion on life expectancy

Because of the integrated exhaust manifolds built into the head, the head temps will be higher,( No Air Flow ) to dissipate heat, if they think the header pipe going to the head will draw heat off the head you have to have air flow around it, the problem is the engine compartment temps when the rad fan is off (not much air circulation), and the head might just cook the oil ( if it's a poor grade) And when the TIC starts the oil system will carry the metal shavings though out the engine, shortening the engine life.

My other observation is the open deck block, the alloy aluminum block, will it take a set, (like cast iron? no!) with the heat extremes this engine can see, I see cylinder movement and wearing of the head gasket, look at it this way how many diesel engine blocks use a open deck, of course compression ratio much higher on the diesel, but both are still internal combustion engine.

How about a server heat extreme - running out of water one time ( a boil over ) how will the block react to that ?

I can't blame Chrysler for going this way after all they have to keep the price down for the consumer and still make a profit, I just wish they went another direction for a power plant, and hope they make a JKtruck before I start to push up daisies.

This is just my point of view folks

33

Oh if you can buy the extended warranty !

Last edited by 33 williys 77; Aug 25, 2012 at 06:56 PM.
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Old Aug 25, 2012 | 06:42 PM
  #102  
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I can't help but wonder if there is any way(if they haven't already done this) to ceramic coat the exhaust ports.

Originally Posted by 33 williys 77
That depends on the maintenance and service of the Penastar, how well you take care of it, driving habits and the environment it's in.

This is just my opinion on life expectancy

Because of the integrated exhaust manifolds built into the head, the head temps will be higher,( No Air Flow ) to dissipate heat, if they think the header pipe going to the head will draw heat off the head you have to have air flow around it, the problem is the engine compartment temps when the rad fan is off (not much air circulation), and the head might just cook the oil ( if it's a poor grade) And when the TIC starts the oil system will carry the metal shavings though out the engine, shortening the engine life.

My other observation is the open deck block, the alloy aluminum block, will it take a set, (like cast iron? no!) with the heat extremes this engine can see, I see cylinder movement and wearing of the head gasket, look at it this way how many diesel engine blocks use a open deck, of course compression ratio much higher on the diesel, but both are still internal combustion engine.

How about a server heat extreme - running out of water one time ( a boil over ) how will the block react to that ?

I can't blame Chrysler for going this way after all they have to keep the price down for the consumer and still make a profit, I just wish they went another direction for a power plant, and hope they make a truck before I start to push up daisies.

This is just my point of view folks

33

Oh if you can buy the extended warranty !
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Old Aug 25, 2012 | 07:36 PM
  #103  
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Originally Posted by RoysRig
I can't help but wonder if there is any way(if they haven't already done this) to ceramic coat the exhaust ports.
Good point Roy:

Maybe some engine builder's and forum vendors might look into this and make some money!

I remember Volkswagon in the fifties, policy was to replace the head with new, instead of rebuilding them.
And a VW dealer in Riverside, Ca said what a waste and started rebuilding these throwaways, that dealer started what is known today as EMPI, talk about success !

33
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Old Aug 25, 2012 | 07:46 PM
  #104  
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Originally Posted by 33 williys 77
Good point Roy:

Maybe some engine builder's and forum vendors might look into this and make some money!

I remember Volkswagon in the fifties, policy was to replace the head with new, instead of rebuilding them.
And a VW dealer in Riverside, Ca said what a waste and started rebuilding these throwaways, that dealer started what is known today as EMPI, talk about success !

33

Same thing with a company in the LSx world. They create the Patriot Head. They had pallets and pallets of oem heads. Sounded like they were not to spec. There was some valve bowl welding that was done, bigger valves added and then port and polish, and sold them for cheaper than any other after market head out there. I would guess they ended up with a good 30-40 percent of the market. A good low cost head for the cash strapped modder.
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Old Aug 26, 2012 | 09:44 AM
  #105  
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I believe the picture is pointing to the right part. I would call it a stationary hydraulic valve lash adjuster. My understanding is it doesn't move but only takes up the slack in the valve train. I don't think that is the part that is causing the ticking sound. I believe the ticking is the valve guide loose in the head or the valve hitting the valve seat off center. Another possibility would be the valve seat loose in the head. I'm no engineer, so take this with a grain of salt.

Last edited by Dale_K; Aug 26, 2012 at 09:50 AM.
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Old Aug 26, 2012 | 09:57 AM
  #106  
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Wow 33 and Roy, sure am glad you're around to explain the complicated mechanics of this engine, and the parts that in theory will wear prematurely. This was over-my-head until you explained it.

My question is...historically, Wranglers run hot (I can barely wear sandles or my feet cook). I don't know why that is, but you're saying that the design and materials used for the Pentastar will not be able to withstand extended high temps and/or the rigors of how we expect our Wranglers to perform on the trail. Which also corroborates the press release from Chrysler about specific conditions which cause the current issues.

Is that right?
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Old Aug 26, 2012 | 11:07 AM
  #107  
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Originally Posted by Wendy.Jeepchick
My question is...historically, Wranglers run hot (I can barely wear sandles or my feet cook).
Hi Wendy:
The reason your feet are hot is the design of the exhaust system, they have to keep it up and out of the way of rocks and brush, close to the tub, heat shields work with air movement, but when you sit in traffic ( coming back from Vegas because of an accident for hours) things heat up, including tempers along with the one finger wave !

33
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Old Aug 26, 2012 | 11:22 AM
  #108  
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Lol...I'm a lady, I don't one finger wave...I just think about it INTENSLEY.
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Old Aug 26, 2012 | 11:27 AM
  #109  
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at what mileage on the odometer is most people starting to experience the tick? and how about some build dates on vehicles that have the tick.
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Old Aug 26, 2012 | 11:33 AM
  #110  
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You can see all the data I have collected here:

https://docs.google.com/spreadsheet/...mb3ZKeFE#gid=0
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