Cylinder head Stud on 1944 2N

[N2N]

New to Forum and have question Re my Dad s old 1944 2N with 12V conversion. Sorry for long post. Tractor was running hot after just few minutes of work. Replaced radiator (which had crack in filler neck), water pump (super old and decided to replace while had hood off) and thermostat. Decided to change fan belt which was in bad shape and found that whoever had done the 12v conversion previously used old generator-size belt and an alternator with large pulley and an old top bracket they d tried to beat and bend to make fit. Belt was super loose and no room left on bracket to pull it tight. So decided to change alternator to one with smaller pulley and top alternator bracket to one that mounts under the two right-front cylinder head studs. NOW THE PROBLEM: When I was unscrewing bolt on right front corner cylinder head stud to put on new bracket, the nut was frozen to stud and when I thought I was unscrewing the nut, I actually unscrewed the entire stud from the bottom. I put the alternator bracket on and screwed stud back in with frozen nut still on it. Seemed to be tightening down okay with torque wrench at first but then just when it felt like it was torquing down to a stopping point (but before I felt torque wrench click) it went loose again. I was not bearing down much at all on it. I m afraid to keep cranking on it for fear I m stripping the threads down in block at other end of stud? Or is it just not getting to tightening point because of additional thickness of alternator bracket under the nut? What do I need to do to solve this problem before I make an expensive mess?
Tractor runs great when I start it. Only ran it a couple minutes and haven t put it to any real work yet. Notice some thin liquid now gathering around top of that front-right corner head stud and trickling down under alternator. Is that coolant? How serious a problem do I have here? Will a new longer head stud and new nut fix this? Thanks in advance for all input.

 

[jimtrs]

(quoted from post at 06:57:15 07/28/22) When I was unscrewing bolt on right front corner cylinder head stud to put on new bracket, the nut was frozen to stud and when I thought I was unscrewing the nut, I actually unscrewed the entire stud from the bottom

Common

I put the alternator bracket on and screwed stud back in with frozen nut still on it. Seemed to be tightening down okay with torque wrench at first but then just when it felt like it was torquing down to a stopping point (but before I felt torque wrench click) it went loose again

Not enough threads screwing into the block because of the thickness of bracket

What do I need to do to solve this problem before I make an expensive mess?

If you got threads of the stud showing above the nut now, those threads need to be in the block. Try unscrewing the stud again, and remove the nut using a vise or such. Screw the stud back in, then add nut. Typically with different brackets on a conversion, this particular nut is just barely on enough

Notice some thin liquid now gathering around top of that front-right corner head stud and trickling down under alternator. Is that coolant?

Yup, Some threaded holes go into coolant passageways. Add some sealant to stud. May wanna drain coolant down below that level first.

 

[Den N Ms]

N2N , Adding the extra thickness of the bracket under the head bolts and not taking the nut off the stud caused the threads to pull on the block.Is there 2 studs that the bracket that bolts to
Drain the block on the left side ,remove the nut from the stud.Take the stud to a bolt or automotive shop and get 2 studs 1/4" longer on the 7/16"NC end and 2 new fine thread nuts pick up a 7/16"NC tap to chase the threads in the block down 1/4" or more and some liquid thread sealer. Take a 5/16' drill bit and run down the two holes in the block by hand with vice grips ect.to clean out crud ,blow out with air chuck.Run tap down holes to clean up threads Put some thread sealer on the studs to prevent coolant leaks and screw them into the block till just snug,put bracket on and fine thread nuts Torque them to 50-55 ft.lbs.don't over do it.Fill radiator and check for leaks.Get the proper 5/8" with pulley and 5/8"with belt.If the stud won't hold you will have to pull the head and helicoil the block.

 

[N2N]

Thank you very much for the reply! Im gonna give it a close look tomorrow and see which fix
gets the job done. Sure hope its the one youre suggesting!

 

[N2N]

Thank you for the reply! That sounds like what I was afraid I was doing I WAS doing. Honestly,
that is sounding way outside my comfort zone without someone standing nearby who knows
what theyre doing. A man has gotta know his limitations



Quick follow up for you or anyone else who may know: Can I run the tractor and do some work
(brush mowing) first, then fix this problem? Or does this need done now before running the
engine under any load?

 

[Tim PloughNman Daley RIP]

Hey N-
FORD used studs on the head to blocks until 1950 then switched over to Hex Bolts. STUDS are a much stronger fastener and are made special. Hardened steel, you will
find studs and hex nuts on the Carb, the exhaust manifold, and the axle trumpets to center housing for example. STUDS have one end with an NC (National Course) thread
and the opposite end has a NF (National Fine) Thread. There is a raw, unthreaded area in between. Coarse threads are ALWAYS used to fasten cast iron with like into the
engine block. The fine threaded end ALWAYS is used to fasten the hex nut with. Guys get into trouble on rebuilds if they fail to understand this and insert the stud
with the wrong end into the block. It is also important to use the correct stud length when rebuilding the engine. Length matters so if too short may strip out or if
too long bottom out and then strip out or not enough thread for hex nut. The N head to block uses two different stud parts as the difference is the length. OEM FORD
Part Number is: 18-6066, 7/16-14 x 7/16-20 x 2.78L, 15 required. Also, p/n 40-6066, 7/16-14 x 7/16-20 x 2.90L, 3 required. Hex Nuts are 7/16-20 UNF and no
washer or lockwasher are used. 14 TPI is the coarse thread; 20 is the Fine Thread; TPI defines THREADS PER INCH. You can get the correct STUDS at places like SUMMIT
RACING I think. When rebuilding the engine, I advise to strip down block and leave studs in. Take it to a good qualified shop to have the block boiled and Magnafluxed
for cracks. Do not buy any new engine kits until it the cylinders are inspected for size as many have been rebored so you don't know what sizes of pistons, bearings,
and sleeves to get until a machinist inspects with precision measuring gages. Often when removing the head and manifold, the studs will come out as well. Suggest you
drain some coolant from system first before starting the job. Your good mechanic will be able to supply you or tell you which engine kit to get after he inspects the
parts.

Tim Daley(MI)

 

[N2N]

Update on this project:
Found a Grade 8 7/16-in stud at a local fastener store with course thread at one end, fine thread at other. A good 1/4-in to 3/8-in longer than original spec, and with a longer course of fine threads, and also maybe 1/8-in more threads on the coarse-thread end. Ran the stud in and out of block hand-tight several times till it felt like it was threading into block smoothly. Then put some high-heat permatex on the coarse-end and ran it into block a firm hand-tight. Ran the nut down tight on fine-thread end. Should ve foreseen this but didn textra length on stud meant my shallow-well socket on torque wrench wouldn t tighten it all the way down and deep-well socket barely gave me room to work under hood. Because it seemed like it was taking forever to tighten up, I was very nervous about over tightening and stripping threads down in block and couldn t see whether I was turning the whole stud. So I switched out to regular open end wrench, not a torque wrench before nut got tight. Took nut down to just a firm wrench-tight, snug but not bearing down hard as I could. Ran for about 4 hrs pulling bush-hog, checking periodically for leaks. No water leaked out. Tractor did not run hot. You guys think I m good on that without trying to figure out actual torque I tightened to?

 

[Den N Ms]

N2N , If you have no leaks levee well enough alone,and let it fly.