Ford 9n Head Studs

[Luke 8n]

Hi yall, I had to drill out a head stud recently and I'm looking for the part number. It appears to be longer than the 3 inch studs since it also goes through the spark plug tube mount. Anyone know of the part number?

 

[wore out]

Hi yall, I had to drill out a head stud recently and I'm looking for the part number. It appears to be longer than the 3 inch studs since it also goes through the spark plug tube mount. Anyone know of the part number?

https://www.tractorpartsasap.com/cylinder-head-stud-new-ford-8n6065a-182477.html

https://forums.yesterdaystractors.com/threads/head-studs-for-8n.1255176/

https://forums.yesterdaystractors.com/threads/8n-head-bolt-or-studs-nut.1306487/

Some info on what you are dealing with.

 

[Tim PloughNman Daley RIP]

Hi yall, I had to drill out a head stud recently and I'm looking for the part number. It appears to be longer than the 3 inch studs since it also goes through the spark plug tube mount. Anyone know of the part number?

1st, STUDS were replaced on the later 8N with HEX BOLTS. Why don't you just get standard 7/16-14 HEX BOLTS? Grade 5 is OK - see LINK.

STUDS are made with an NC (National Coarse) threaded end and an NF (National Fine) threaded end. Know the difference first of all. The NC (7/16-14) end always goes into the cast iron part. The top end, 7/16-20 always accepts the hex nut fastener. Unknowingly if you insert the fine end into the block you'll booger up the tapped hole. STUDS are made of hardened steel and pretty robust. Cast Iron is softer, more brittle, and less forgiving so if you cross thread the tapped hole, a machine shop will have to fix. From an engineering standpoint, STUDS are a stronger/better fastener than a hex bolt.

OEM Part Numbers and SPECS for the CYL HEAD STUDS are, there are18 total, 15 at 2.78", 1 at 2.9". KNOW which go where!
18-6066 - 7/16-14 x 7/16-20 x 2.78"
40-6066 - 7/16-14 x 7/16-20 x 2.9"
You can get new studs at DORMAN for one but I'd just get new hex bolts and make things a lot simpler.

NOW, that all being said, FORD later obsoleted the studs and went to a standard 7/16-14 x 1-3/8" HEX BOLT. LINK:

7/16-14 x 1-1/2" GRADE 8:

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

These are 1-1/2" Long but may be OK on the head. Take a pencil and measure depth of all 18 holes to top of head. If too long, you will have to grind off an 1/8" from end.

Grade 5 is 60,000 PSI Tensile Strength and should be OK.
Grade 8 is 150,000 PSI Tensile Strength and will be better.

Some opt for Stainless Steel but that is an overkill.

Head STUDS and BOLTS DO NOT use any washers - flat or lock.


Your Mileage May Vary,
Tim Daley (MI)



Tim Daley (MI)

 

[Fixingfarmer]

Head bolts if I switch out studs I use grade 8 on everything this vintage. Phosphate and oil coated ones are best don’t have to lube and don’t have to worry about a zinc coating. Caterpillar happens to supply. I’m sure there are others just not locally for me

 

[Luke 8n]

Thank yall for the replies. I think I may just switch to head bolts to make things easier.