I have an 8305512 -15 port fabricated liner with an upper air box seal groove. The seal is not available and the upper seal groove was deleted in all newer designs. Is there a problem installing the liner in a BC crankcase leaving the upper seal groove empty? I am assuming right now that the upper pilot bore diameter on the old standby 8300780-20 port 'C' liner that is coming out was not changed on the 8305512 liner we have as a replacement (we'll measure to be sure) and that using this 15 port liner will not effect scavenging efficiency in any meaningful way in the ultra light duty cycle this locomotive sees. Anybody out there 'been there-done that"? Thank you!

I passed your question along to a retired EMD Service Engineer, who responded as follows:

"Boy oh boy, talk about going back into the memory banks. First, you should not have to install that "O" Ring in the upper liner groove. The catch is, what is the condition of that upper-liner bore? If there is a wear "groove" in the upper-liner bore, from the old "O" Ring, then you might have a problem. At any rate, maybe a lower liner "O" Ring seal could be made to work.

Now, concerning the use of a 15 port liner instead of an original 20 port liner is OK, and in fact EMD even issued a recommendation (Pointers article?) about the use of 15 port liners in engines still equipped with 20 port liners. Just going by memory, they didn't want you to place them adjacent to one another, nor exceed 4 per 16 cylinder engine.

If you need more specifics, let me know and I'll go into the attic and research my EMD historic stuff."

I'd bet money that P. Cook knows a bit about this subject, too.


Hope this helps.

Lincoln Penn --
Would you please be so kind as to ask if your retired EMD Service Engineer friend would be able to scan and thus digitize his priceless EMD documents? That kind of stuff is usually irreplaceable, and I worry what will happen to it after your friend is gone. People caring for those wonderful old EMD locomotives really need info like that, and it really should be digitized, if at all possible. (I know -- who is going to pay to do all that, and who even has the time?)

Hoping for the best for that EMD material!

richard --
I hope you can find something that works.

You need a copy of "Pointers" from June 6 of 1972 for details on your interchangeability issue. The way I read it you can mix 15 port and 20 port in any combination and location in an AC, BC, C, and D1. There are, however, much stricter terms for mixing them in a 567 turbocharged engine.

I also recall a note on the elimination of the upper O ring, but haven't laid hands on that reference yet. I can tell you that the several HLPs I've put in lately didn't have/get them even though the liners appeared to still have the groove. Our friends at PowerRail make an "enhanced" version of the brass/bronze head seat ring that has a rubber seal around the OD and this is what I normally will use when we make a replacement. It tends to help a little bit with the "souping" issues.

ETA
Two Cycle, Tennessee

Yes, Lincoln Penn, than information sounds quite accurate. The upper liner seal is no longer manufactured or used, they found that the carbon from the exhaust side sealed up the clearance very quickly after installation and a baked in liner seal made the pack more difficult to remove. The groove continued to be machined in the liners for years afterwards.

I recall seeing notices stating both three and four of the 15 port liners as being the limit for replacements in turbocharged 567's that originally were built with 20 port liners. EMD allowed random mixing of 15 and 20 port liners in roots blower 567's, so the 567BC in question could use either type in any mix.

The notification was carried forward in the EMD parts catalog 300.

From Catalog 300, 6th Edition, September 1985, List F106, Page 3:

"Normally aspirated 567 engines can mix 15 port and 20 port liners without restriction. Early turbocharged 567 engines with 20 port liners can apply no more than three 15 port liners in an engine."

And yes, this kind of information is absolutely essential to maintaining and operating older EMD equipment in museum and tourist railroad service. It would have been a valuable contribution to the cause if some national organization had established and maintained a comprehensive library of such publications in support of preservation, if they were interested in preservation, and if they had any interested in diesels.

PC

As an aside:

If you aren't planning on picking up Trains Magazine's "Locomotive 2014", change your mind.

Mr. Cook's article alone makes it worth the price.

I seem to remember IRM having an EMD library, but I have no idea whether or not it includes things such as "Pointers" or the various editions of parts manuals.

I don't take credit for it. I'm just the messenger, passing it along.

I had assumed the upper groove was added to the design with turbocharging to better contain higher air box pressure. More interesting though is Preston's insight as to why it was removed.

Thank you all for the assistance and for the knowledge sharing resource provided by RPN.