Head bolts 8n

[TasCanada]

I plan on getting the screws and washers as recommended below (on this site) to replace my head bolts. Question is - do the torque specs change because of the washers? If so what would they be?

Secondly I had 15 bolts and 3 studs with nuts - can I replace them all with these screws?

Thanks...

[color=darkblue:25c91c2309]
[b:25c91c2309]
"The OEM bolt was 7/16-14 x 2 3/8 grade 8. Good luck finding that size bolt in 2 3/8". So, replace the OEM bolts with 7/16" -14x2&1/2" yellow zinc finish SAE j429 grade 8 Hex Cap screws Part # 0115163 from Fastenal for $0.89 each. Use flat washers 7/16" yellow zinc finish SAE thru-hardened from Fastenal Part # 1133816 for $0.19 each. "[/b:25c91c2309][/color:25c91c2309][/b]

 

[TheOldHokie]

(quoted from post at 19:03:28 09/06/18) I plan on getting the screws and washers as recommended below (on this site) to replace my head bolts. Question is - do the torque specs change because of the washers? If so what would they be?

Secondly I had 15 bolts and 3 studs with nuts - can I replace them all with these screws?

Thanks...

[color=darkblue:cb22b2e45b]
[b:cb22b2e45b]
"The OEM bolt was 7/16-14 x 2 3/8 grade 8. Good luck finding that size bolt in 2 3/8". So, replace the OEM bolts with 7/16" -14x2&1/2" yellow zinc finish SAE j429 grade 8 Hex Cap screws Part # 0115163 from Fastenal for $0.89 each. Use flat washers 7/16" yellow zinc finish SAE thru-hardened from Fastenal Part # 1133816 for $0.19 each. "[/b:cb22b2e45b][/color:cb22b2e45b][/b]

I would go with 7/16-14 x 2-1/4" and no washers. Available in boxes of 10 from, McMaster for $7.50/box.

TOH

 

[Royse]

(quoted from post at 19:41:21 09/06/18)

(quoted from post at 19:03:28 09/06/18) I plan on getting the screws and washers as recommended below (on this site) to replace my head bolts. Question is - do the torque specs change because of the washers? If so what would they be?

Secondly I had 15 bolts and 3 studs with nuts - can I replace them all with these screws?

Thanks...

[color=darkblue:2a7b7d5de3]
[b:2a7b7d5de3]
"The OEM bolt was 7/16-14 x 2 3/8 grade 8. Good luck finding that size bolt in 2 3/8". So, replace the OEM bolts with 7/16" -14x2&1/2" yellow zinc finish SAE j429 grade 8 Hex Cap screws Part # 0115163 from Fastenal for $0.89 each. Use flat washers 7/16" yellow zinc finish SAE thru-hardened from Fastenal Part # 1133816 for $0.19 each. "[/b:2a7b7d5de3][/color:2a7b7d5de3][/b]

I would go with 7/16-14 x 2-1/4" and no washers. Available in boxes of 10 from, McMaster for $7.50/box.

TOH

I understand (or think I do) the length decision Dan, and no washers due to that.
I've had several with washers though. Some on studs, others on bolts.
Any problem with the washers themselves or just the length/reach?
I'm not currently in that situation, just curious.

 

[TheOldHokie]

(quoted from post at 20:41:03 09/06/18)

(quoted from post at 19:41:21 09/06/18)

(quoted from post at 19:03:28 09/06/18) I plan on getting the screws and washers as recommended below (on this site) to replace my head bolts. Question is - do the torque specs change because of the washers? If so what would they be?

Secondly I had 15 bolts and 3 studs with nuts - can I replace them all with these screws?

Thanks...

[color=darkblue:4481f5d372]
[b:4481f5d372]
"The OEM bolt was 7/16-14 x 2 3/8 grade 8. Good luck finding that size bolt in 2 3/8". So, replace the OEM bolts with 7/16" -14x2&1/2" yellow zinc finish SAE j429 grade 8 Hex Cap screws Part # 0115163 from Fastenal for $0.89 each. Use flat washers 7/16" yellow zinc finish SAE thru-hardened from Fastenal Part # 1133816 for $0.19 each. "[/b:4481f5d372][/color:4481f5d372][/b]

I would go with 7/16-14 x 2-1/4" and no washers. Available in boxes of 10 from, McMaster for $7.50/box.

TOH

I understand (or think I do) the length decision Dan, and no washers due to that.
I've had several with washers though. Some on studs, others on bolts.
Any problem with the washers themselves or just the length/reach?
I'm not currently in that situation, just curious.

Just keeping it simple. You would have to tie me up and drag me into Fastenal for anything other than construction fasteners....

TOH

 

[Hobo,NC]

A washer will act as a bearing they will affect the torque when used... Its recommended to sand the washer to make it bite and take the bearing effect away from it... Are sum'N like that I googled it fer ya...

https://www.enginelabs.com/engine-t...-avoid-pulling-threads-or-killing-head-bolts/

 

[Tim PloughNman Daley]

No washers needed really -OEM never did. First of all, torque is measured by the size and material type of the FASTENER and has nothing to do with a washer. Secondly, you need to understand the difference between a stud and a hex bolt. Your engine block is made of cast iron. Cast iron requires a COARSE THREAD for fasteners as FINE THREADS do not work well in the material -it strips out easy for one thing. That is why all your fastener holes in cast iron have coarse threads. Thirdly, a stud is one nominal size, for the head it is 7/16" BUT, one end is a COARSE (7/16-14 UNC) thread which screws into the block and the other end is a FINE (7/16-20 UNF) thread which accepts a 7/16-20 hex nut. 14 TPI (Threads Per Inch) and 20 TPI have different torque specifications, follow? There is a chart over on the LH side of the YT Home Page under RESEARCH/TORQUE VALUES. It is difficult to find the correct stud lengths nowadays, and many have changed over to hex head bolts. You do know that torque specs are different for each, right? Like TOH said, forget Fastenal and TSC -they are overpriced junk stores, and only carry a minimal stock of standard sizes. You can get the hex head bolts at McMaster-Carr - see LINK below. Original Ford head stud is p/n 18-6066, 7/16-14 x 7/16-20 x 2.78" L, 15 required AND p/n 40-6066, in the same nominal size but length is 2.90", 3 required. The 3 longer ones go in specific holes -your MPC will show which ones. The original Ford p/n for the hex bolt is 8N-6065-A, 7/16-14 x 2-3/8"L (18 rqd.) and the price is expensive from suppliers varying from $5 per bolt to 11.50 per bolt at McM-Carr for the partially threaded ones. The LINK has the fully threaded style, Check hole depth first as you may have to grind 1/8" off a few. Priced at $8.50 Grade 8, per 10 pieces so for $17 you get 20 and there are 18 required. You don't need washers -the OEM setup didn't. Torque and torque wrenches are often misunderstood. There are different SCALES of which to measure. There are INCH-OUNCES, INCH-POUNDS, FOOT-POUNDS, and NEWTONMETERS. It is important to know what scale you are in so the settings on the wrench are correct. The correct method of torquing something is in three steps. Take the finish spec, say 54 FT. LBS. and divide by 3. 54/3=18. You follow the TORQUE SEQUENCE chart and begin the first pass at 18 FT/LBS. Then reset the wrench to 36 FT/LBS and repeat sequence. Final pass is at nominal setting of 54 FT/LBS following the chart sequence. After running the tractor once or twice and getting things nice and hot, you can recheck the torque after it cools down. You will need a swivel head socket adapter for the torque wrench in order to sneak next to a few places like the wire loom that attaches to two head studs. There is not much clearance between the tank and the head so it can be tricky. The job goes a bit smoother with the hood off. Also, using a torque wrench is only effective in the tightening direction -NEVER use one to loosen a fastener with -that will ruin/decrease the life and effectiveness of the tool. When adjusting the settings, be sure to UNLOCK the locking ring first, then always turn the wrench thimble nut back a few turns to take out any backlash and then slowly advance the thimble until the correct setting is hit on the main scale of the tool. Lock the locking securely once setting is met. Here is a torque chart for the N Cylinder Head:

Tim *PloughNman* Daley(MI)
7/16 14 x 2 1/2 HEX HEAD BOLTS

 

[Tim PloughNman Daley]

I just spent an hour trying to find a 7/16 stud to replace the OEM ones used on the N-Tractor cylinder head. My usual go-to sources do not offer one. I did find one -see LINK below that is perfect and the price is about $31.80 for 20 pieces, $39 with shipping. The length is 3", more than the OEM, but you can grind down the ends to match. MPC lists 15 at 2.78"L and 3 listed at 2.9" L. Caution is advised to ensure the thread length isn't too short or too long. You do not want the stud to bottom out on the non-threaded shoulder nor not have enough thread for the nut. The OEM hex nuts have an 11/16" AF dimension too, and I could not find any hex bolts like that other than the ones nnalert sells at $5 per bolt, specially made with 11/16 AF hex head and length at 2-3/8?. McM-Carr sells a 7/16-20 Hex Nut, Grade 9, exact of original with 11/16" AF and 7/16" thickness. For the costs involved, I'd opt for the studs and hex nuts. 20 STUDS @ $39, plus 20 HEX NUTS @ $23.56 (using $7.80 shipping)equals $62.56. That seems like the best way to go and gives you two each spares.

OEM style hex nuts: https://www.mcmaster.com/95036a037

Tim *PloughNman* Daley(MI)
7/16 STUDS BEST BUY

 

[Tim PloughNman Daley]

OK -STEINER TRACTOR sells the same 7/16 x 3" STUD for $4.50 each...Steiner always has been overpriced...

TPD

 

[TheOldHokie]

(quoted from post at 05:31:21 09/07/18) First of all, torque is measured by the size and material type of the FASTENER and has nothing to do with a washer.

Bolt torque is used as an indirect (and relatively inaccurate) indicator of bolt tension - e.g. clamping force. The fastener tension produced by any given torque is very dependent on the friction characteristics of the fastener and the structural characteristics of the connection. Putting a washer under the head of a bolt, lubricating the threads, or altering the surface conditions under the head of the bolt will change the torque needed to get a specific tension. You cannot rely on fastener size and material alone - if you do you risk over tightening and deforming the fastener, stripping threads, or generating inadequate clamping force. A hardened and coated washer under a head bolt WILL affect the torque needed to produce the same tension as a washerless connection. How much is the million dollar question and can only be accurately answered by actual field testing using a more reliable and direct method of tension measurement. That is how OEMs arrive at their head bolt torque recommendations - not by a generic torque table lookup but by empirical testing on a test bench. In this particular case the difference is probably not consequential but you need to understand you are altering the friction characteristics and changing the outcome by adding a washer.

TOH

 

[TasCanada]

Do appreciate all of the advice... Thanks much.

Any idea why I had 15 bolts and 3 studs in there? The studs are the same length as the bolts (the part below the nut) except for one which is a few millimetres shorter

 

[Jim L WA]

TasCanada, your tractor is 69 years old, give or take. someone's been there before you. Needed to replace 3 bolts, couldn't find the correct ones or didn't want to pay for them and put studs in. The earlier 9N/2N's used all studs.

 

[HFJ]

"I just spent an hour trying to find a 7/16 stud to replace the OEM ones used on the N-Tractor cylinder head. My usual go-to sources do not offer one."

i don't know who your usual sources are, but when i rebuilt mine, i got the proper studs from my local auto parts store.

 

[TasCanada]

(quoted from post at 13:00:40 09/07/18) TasCanada, your tractor is 69 years old, give or take. someone's been there before you. Needed to replace 3 bolts, couldn't find the correct ones or didn't want to pay for them and put studs in. The earlier 9N/2N's used all studs.

This is what I suspected but just needed to be sure... thanks

 

[Tim PloughNman Daley]

I use the usual parts suppliers listed here and the reliable ones well known in the business. Auto parts stores rarely have $hit I need... tried recently for carb studs and not a chance in hell...

TPD

 

[Tim PloughNman Daley]

Yep -like Jim said above. Somebody was lazy and took a shortcut. Probably went to their local auto parts store and found out they stocked diddly-squat. You need to get the manuals so you know which holes take the longer studs.


FORD 8N OWNER ESSENTIAL MANUALS:

TPD

 

[Tim PloughNman Daley]

Yes, a perfect explanation Dan, but I didn?t want to get too technical with a newbie. What many fail to realize is that the torque spec chart was when everything was brand spanking new on the line. Ford was supposed to use a minimal dab of plain engine oil on fasteners. Want to bet many got by without? Mostly it was for fast and easy assembly. Once the fastener gets plastically deformed, the characteristics change. Oil, rust, plastic deformation will all affect true torque values. The chart is just a guide to use when doing the job and I wouldn?t put a whole lot of ?got to be absolute? emphasis on it. Just keep the tension as even as possible and follow the sequence. It ain?t rocket science. Now machining plutonium -that?s rocket science! Ask me some time.

Tim Daley(MI)

 

[TheOldHokie]

(quoted from post at 18:43:26 09/07/18) Yes, a perfect explanation Dan, but I didn?t want to get too technical with a newbie. What many fail to realize is that the torque spec chart was when everything was brand spanking new on the line. Ford was supposed to use a minimal dab of plain engine oil on fasteners. Want to bet many got by without? Mostly it was for fast and easy assembly. Once the fastener gets plastically deformed, the characteristics change. Oil, rust, plastic deformation will all affect true torque values. The chart is just a guide to use when doing the job and I wouldn?t put a whole lot of ?got to be absolute? emphasis on it. Just keep the tension as even as possible and follow the sequence. It ain?t rocket science. Now machining plutonium -that?s rocket science! Ask me some time.

Tim Daley(MI)

There are no "true torque values". There is a tension you want to produce and torque is merely an indicator for that. Lots of variables including washers in that equation. Bolt torque charts are generic guides that have a lot of assumptions built in and even newbies need to understand that.

So what plutonium have you machined and where and for whom? That's a pretty exclusive club and pretty much limited to government weapons labs.

TOH

 

[Ken(Ark)]

The head bolts go into the water cavity . The threads in the block below where the old head bolt stopped may be plugged up . On a few of those holes , especially the back corner over the exhaust , it may crack the block if a longer bolt is used . It tends to force the excess material outward instead of into the water jacket .

Since these bolts go into the water jacket , they may leak coolant if no sealer is used . If sealer is used it may lubricate the threads and change your torque values .

Old studs may be extremely hard to remove and breaking one is common . Extracting a broken stud that did not want to come out in the first place is not a fun project . That could be why you have some bolts and some studs .

From an engineering stand point studs will seal better , torque more consistent , and usually have more contact area and less stress with the cast iron threads , but bolts are much easier to use in most cases . Either way will work just fine if you check your parts closely . I don't think I have ever heard of head bolt failure on these motors when common sense / average mechanical abilities were used . A basket case motor / ran when parked 15 years ago could be an exception .

Someone will correct me if I am wrong , but I don't think grade 8 is needed and grade 5 will proved all of the strength needed . The supplier you use may be close on the price or have the 8's really jacked up .

Flepro 7277-B makes a really good head gasket and can usually be ordered from your part store in a day or so , or ordered from the net . I usually get mine from e bay delivered to my mailbox .

 

[TasCanada]

Which of these manuals would indicate the holes for the longer studs? All of the bolts/studs that came out were the same length except for one that was slightly shorter.
Thanks

 

[FarmerDan2018]

The two studs that hold the throttle linkage bracket and the one that holds the spark plug loom tube are longer than the other 15 studs/bolts.