Factory cylinder head install

[gondola993]

I've been told by Cummins technical folks, including engineering, that an independent engine builder, such as myself, could never install the cylinder head as well as the factory. They said that no matter how skilled the builder, the installation will never be as good as factory. After many decades of mom & pop built engines, following time honored techniques, I find Cummins' conclusion hard to accept. What do you guys think. What is so special about a factory bolted down cylindr head?

Thanks

 

[pontiacjack]

I'm just guessing: a multi-spindle machine that simultaneously torques all head fasteners?

 

[pontiacjack]

I should have noted: all fasteners of ALL heads, if a V-configuration engine.

 

[badservo]

I can't say that I am very impressed with the factory job on the 200kW generator here. The replacement head gasket I put on seems to be be doing just fine and has almost the same hours of use. Having to run at 60-80% load with no warm up time is not healthy and may be to blame, but it is a backup generator.

 

[dicer]

The multispindle machine is hard to beat for even torque. But it still depends on who's doing the job.
Now if all said parts at the factory don't have a human touching them, then I would agree with the Cummins statement. Most that twist wrenches can be pretty haphazzard doing some of the important prep operations in doing certain jobs properly.

 

[patprimmer]

I disagree with the factory comment. If it is done right, it matters not where that is. I would agree with a comment that it is very unlikely that an independent repair shop can do as well as the factory, but I would not agree with NEVER.

Regards
Pat
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[Tmoose]

I'd ask the Cummins engineer ( if he still works for Cummins ) to share an example or two of the factory-only goodness, or every indies' shortcomings. Seems to me if "not as well" has any actual technical significance (or even if "it" does not) it also could be put into a short bulleted list at least.

Also, I wonder if factory trained techs at Cummins' authorized repair centers learn the tricks, get the good parts, or whatever it is that independents lack.

Supposedly in the early days the cylinder heads of Corvette engines, unlike the passenger car engines, had their cooling passages filled with shaving cream so as they were being presented to the block on the assembly line no core sand could fall into delicate regions.

I know of a few instances when the (non Cummins) Central Office zone rep enlisted help from crafty dealership techs who on their own had figured out successful fixes for ugly factory installed/designed-in f*ck-ups . VW paid a friend handsomely to put on a powertrain rebuilding "school" using the techniques he had developed to chop 80% off the factory time for some oft required (!) warrantee overhaul procedure.

 

[ivymike]

I'm sure he was referring to the advantage that the multi-spindle torqueing machines can give... in some instances the factory (not necessarily Cummins) will also directly measure bolt stretch while torqueing to ensure the correct pre-load (vs. torque/turn or other methods).

 

[TheBlacksmith]

New block, new head, new bolts, multi-spindle machine should result in near perfect torque. However, a skilled and caring aftermarket mechanic can get close enough that it shouldn't matter to the longevity of the build. As someone else said in a post here, anytime you use the word never or always, you're likely to be wrong (but not always!).

 

[gondola993]

Thanks. I appreciate everyone's input.

 

[Tmoose]

Hi Gondola,

Do you think you'll get the chance to ask the Cummins engineer to of the indies' shortcomings?

Dan T