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Discussion Starter #21
Just a quick story. When I first got my TC a couple of years ago the PO had done quite a bit of work, replaced the turbo, head was refurbished, etc. It still smoked after running for a while.

I found that the valve stem seals it had in it were wrong. They were too tight around the valve itself and I swear had a little metal band around them for the boss, but the seal was blue (nitrile?). Anyway, they would stick on the valve and pull up off of the head boss allowing oil under them and into the guide area. I replaced them with standard seals...no problems since.
Hey that is a great real world example and exactly the kind of thing that we DONT want to happen to us.. When we play musical parts trying to make things "better" for the sake of being different, we sometimes make things worse. Chrysler engineers had thousands of hours, millions of dollars, years of schooling and pretty much had things sorted out. Of course we all accept that the years has seen many improvements in technologies, materials and designs and that in the end is what we are looking for. I have all the specs for the top OD of the valve guides, the specs for the OD of the valve stem and the specs for the desired valve stem seal height, after it is installed to allow for stock and high lift cams. And to your point, if you choose a 'different' seal that was actually intended for another application, and it doesn't have the right spec (too small for the stem) then you get BS problems like them popping off anyway...which was what we were trying to prevent in the first place.

Thanks so much for sharing and for helping to confirm, that the correct part that gets the job don't is always better than 'bling' for the sake of bling.
 

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sry I built that head 10 years ago and bought the seals here on TD from another member that had bought a set of 16 from eBay

I can't 'search' my Private Messages to try to go back in time and review the transaction

as I recall they were 3rdGen '03-'08 (non VCT) 5.7 Hemi..
they weren't OEM bits, they were aftermarket of some kind...

AND I have since sold that head so I can't even go look at it or take pix ...

I do remember the machinist said they slid right on as intended, no mods required.
 

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Discussion Starter #24
I think that eventually this thread is going to yield some good information and already I think we've all learned something new, it's good. I did want to bring out the point that the OD of the valve guide and the OD of the valve stem are both known and consistent across all our heads UNLESS you are using over-sized guides or custom valves. So, with that being said we are talking about stock sizes here.

The company SBI is an automotive standard supplier of many engine parts. Almost any machine shop will have one of their catalogs. The beauty of the catalog is that it has every part that they make or distribute cross referenced in a variety of tables that make it easy to (for example) look up any style valve stem seal that has a valve stem hole size of .xxxx" So, you just run your finger down that column till you come to the seals in that size, or within 1-2 thousandths of an inch smaller to that size. Then you look across a column or two to find the seal on those lines that has the correct ID size to fit the OD of the valve guide. So now you have a seal that fits your application, and then you look to see if it is a positive metal clad, a high-hat style, a rubber/silicon/vitton (all rubber), style etc. Lastly, with the part number in the last column, you can look that number up and see what applications they fit. So in the end you know that the seal will fit our applications and what car/truck/tractor engines they came on and what years.

We went down the entire Chrysler selection of valve stem seal applications and every engine in the book, none, not one of the 'hemi' engine seals was a fit. I am going back by the shop again today to gather up a little more info, just wanted to share how and where this information is coming from...and where it is going to which is a list of valve stem seals that are known to fit properly, and work w/o having to do any modifications to the head.
 

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Discussion Starter #25 (Edited)
HERE ARE A FEW ILLUSTRATIONS THAT GIVE THE SIZES REQUIRED TO FIT OUR VALVE STEMS AND VALVE GUIDES.




An important note to make is that you do not want the rubber portion of the seal resting on the top of the valve stem guide. The constant up/down of the valve stem will pretty quickly hammer the rubber enough to break it or crack it. There needs to be some gap between the top of the valve guide and the bottom of the rubber portion of the positive metal clad seal.

What you dont want is any type of seal that doesn't fit snugly over the top of the valve guide forming a positive seal because, if it isnt sealing every time the valve opens and the piston moves down, there will be a vacuum created and the vacuum will suck engine oil past the valve stem and guide right into the engine to burn...i.e.: smoke while running.
 

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Discussion Starter #27
MAHLE B45798A
Alternate/OEM Part Number(s): 53009886

THIS IS THE SEAL FOR THE 5.9 MAGNUM (LA) MOTOR BUILT FROM 1993 - 2003. THIS SEAL IS TOO SMALL FOR THE VALVE STEM AND TOO LARGE FOR THE GUIDE.

 

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Discussion Starter #29
Fel-pro ss70945 {#MAHLE b45919, b45922} (REFERENCED ABOVE DOES NOT SEEM TO BE A GOOD CHOICE ACORDING TO THE PUBLISHED SPECS FOR THE SEAL. IF THE SPECS I FOUND ON THE MAHLE/VICTOR REINZ SITE ARE CORRECT THIS SEAL IS TOO TIGHT ON THE STEM, AND TOO LOOSE ON THE GUIDE SO IT IS GOING TO BE VERY PRONE TO POPPING OFF AND STARVING THE VALVE & GUIDE OF OIL.

EVEN ON AN OVERSIZED GUIDE THE FIT OF THE SEAL IS GOING TO BE A BIT SLOPPY.

 

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I had one of Jegs regular spam specials emails last week with a listing that showed a seal example - that being for MAHLE cryco hemi valve seals .. 09-15

being in the flyer art there was no link to be saved sorry

I know for absolutely sure I read a "to use post" about 6-8 years ago , right here saying to use 2010 hemi (5.7) seals - not to say use these , but that I'd seen the post ..

I know I'd have saved a link to that but my 2.2 file has grown outta control ... along with the sub folders
 
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