866 V8 gasket set locating

[Full Floater]

I have a previously good running 866, that has dropped a valve seat.  No engine damage.

I realize that most parts are near obsolete for these now, but if there are any lingering upper gasket sets out there somewhere that can be had, I will give this particular engine another chance before it's pulled and parted out.

Any current leads on 866 head and manifold gasket sets?

Edited November 10 by Full Floater

[Joey Mack]

all I can offer is part numbers.  126SB 181A,,,,  and 126SB 182A.. gasket kits for that engine. 

[Full Floater]

1 hour ago, Joey Mack said:

all I can offer is part numbers.  126SB 181A,,,,  and 126SB 182A.. gasket kits for that engine. 

Wow, that's good information.  Thank you.

[Joey Mack]

I highly recommend finding this book.  It has a lot of part numbers. It is one of my go to books.    Jojo

[Joey Mack]

I will try to remember posting the head gasket number later when I get home.   

[h67st]

Here's a pdf copy of that KSA book.

https://www.bigmacktrucks.com/assets/ksa_book.pdf

[D-Day]

John Chalmers 717-334-8709, Chalmers sales is in Cashtown PA I got a complete engine gasket set from him 2 years ago he has some other parts as well 

[fjh]

PAI has oversized seats!

[Joey Mack]

Head gasket for ENDT (B) 865-866 is: 57GC 199

[Full Floater]

On 11/10/2025 at 4:54 PM, fjh said:

PAI has oversized seats!

Thank you!  Is that the proper "fix" for them?

[fjh]

2 hours ago, Full Floater said:

Thank you!  Is that the proper "fix" for them?

yup

[CF-Firefighter]

I’m trying to learn more about the 865/866 myself. I have an 865 and am beginning to collect parts for future repairs. Thank you for the part numbers. 

[mowerman]

i thought i saw watts recently offering complete engine overall kits for those  was very recent,,,i thought i remembered somewhere around $8,000 good luck,,,bob

[Full Floater]

3 hours ago, mowerman said:

i thought i saw watts recently offering complete engine overall kits for those  was very recent,,,i thought i remembered somewhere around $8,000 good luck,,,bob

I believe those are E9 kits.   Seems like a good price however, for an E9

[Full Floater]

4 hours ago, CF-Firefighter said:

I’m trying to learn more about the 865/866 myself. I have an 865 and am beginning to collect parts for future repairs. Thank you for the part numbers. 

Me too.  I understand that they were not the BEST platform out there, but if we have some good running ones, i'd like to keep them that way and use them within their limitations, reliably....for as long as we can

[terry]

21 hours ago, fjh said:

yup

And throw them in the freezer before installing them?    terry

[Vladislav]

51 minutes ago, terry said:

And throw them in the freezer before installing them?    terry

Valve seat? That's not a valve guide.

As I was told in a local shop they use liquid nitrogen for cooling seats. And although valve guides, surface grinding and many other jobs are made by guys the seat installation is done by the chief himself.