I just picked up a barn find 1974 Doncaster built International Harvester 674 and have got it running nicely now after bypassing keystart and bleeding system. I will need to service, remove cab and strip it all down to clean/service and eventually respray. I am new to these IH machines and being in Europe all my tools are metric. So i figure its now time to get away from the vise grips and adjustable wrench before i destroy fasteners. I will be getting a few standard/ SAE sets but want to ensure i have all sizes covered. Do any of you know what size range do i need to have to cover this machine and is there any particular size that comes up most of the time. I aim to get a 1/2" drive impact socket set and an SAE Combination wrench/spanner set that should cover 90% of whats needed, but i may also pick up a ratcheting spanner for 1 or 2 really common fastener sizes. Also is there anything else in SAE/Standard that i should be thinking of ?
IH 674 fastener / wrench sizes
- Thread starter Alaniho
- Start date
I'd suggest joining yesterdaystractors.com I'm sure they have a brand-specific subforum for Int'l Harvester. That site has a knowledge depth on par with this site.
Those folks will be able to help you out and generally are good people. I won't be much help as my tractor is 20 years older and a Ford.
Those folks will be able to help you out and generally are good people. I won't be much help as my tractor is 20 years older and a Ford.
thanks, yes thats good advice i had joined up to the Red Power Forum as they seem to specialise in Case / IH and got some good tips there, as per below just for reference for any one else with a similar query. Helpful lads over there and i hope MrFred54 does not mind me passing on this piece of advice.
5/16-1,1/4 set of sockets and end wrenches should just about cover everything. Best way to go with sockets is with 3/8 drive,5/16-3/4 and 1/2 drive,3/8- 1,1/4. Size most often used is probably 1/2,9/16,3/4,15/16. Good luck and welcome
5/16-1,1/4 set of sockets and end wrenches should just about cover everything. Best way to go with sockets is with 3/8 drive,5/16-3/4 and 1/2 drive,3/8- 1,1/4. Size most often used is probably 1/2,9/16,3/4,15/16. Good luck and welcome
Tools for working on IH 674
Hey everyone, first post so go easy on me. I just picked up a barn find 1974 Doncaster built IH 674 and have got it running nicely now after bypassing keystart and bleeding system. I will need to service, remove cab and strip it all down to clean/service and eventually respray. I am new to these ...
www.redpowermagazine.com
RedneckWelder
Well-known member
24mm is equivalent to 15/16, 22 is 7/8, 19 is equivalent to 3/4, 16mm is 5/8, sometimes you can use 14mm for 9/16 but it sometimes won’t work, same for 13mm and 1/2. 11 and 7/16 are usually pretty close.
Above 19mm or so oftentimes metric and standard are close enough to get buy with many sizes (most of my 3/4 sockets and larger wrenches are SAE)
Above 19mm or so oftentimes metric and standard are close enough to get buy with many sizes (most of my 3/4 sockets and larger wrenches are SAE)
Truth. I have a Snap-on 1/2" deep impact stamped 3/4" on one side & 19mm on the other
RedneckWelder
Well-known member
My 3/4 drive sockets (SO/Williams/Cat) sometimes have both sizes stamped
Dave455
Well-known member
I don’t have any experience of those particular tractors, but it sounds as though you are not familiar with imperial sized fasteners, so perhaps I can offer some advice.
I assume that the bolts on your machine are Unified threads. The majority will be UNF (Unified Fine) but you will also find UNC (Unified Coarse) if they are threaded into iron.
The wrench sizes you need are generally referred to “SAE” in the U.S. (Society of Automotive Engineers, who originally specified the wrench sizes) and “A/F” (Across Flats) in the U.K. and europe.
It’s useful to know what size bolts are used on your vehicle, and what wrenches fit them.
Most British built machines of that era are held together with 1/4”, 5/16” and 3/8” bolts. You will find them where you find 6, 8 and 10mm bolts now. The appropriate wrench sizes are 7/16”, 1/2” and 9/16”. You will use these a lot. Maybe a 3/8 wrench on a 3/16 bolt if your machine has them.
The bigger wrench sizes you might need are 5/8, 11/16, 3/4, 7/8, 15/16 and 1 1/8. These will cover you up to 3/4” bolts.
Smaller A/F sizes are only used on UNF “numbered series” fasteners, but…. Unified “numbered series” were not adopted in the U.K. (other than in the aerospace sector) so you hardly ever find these. What you may find are “BA” (British Association) fasteners instead. Even numbers are preferred, so a 2, 4 and 6 BA will do most of what you need.
If your tractor was built to a U.S. spec it could feature the smaller A/F fasteners, but that would be rare!
You may also find British Standard (Whitworth) sizes on your hydraulic fittings. Again, the U.K. never adopted Unified pipe thread (I’m not sure there was one) so used (and still uses, as does most of the world) BSP (British Standard Pipe) threads.
Hope that helps!
I assume that the bolts on your machine are Unified threads. The majority will be UNF (Unified Fine) but you will also find UNC (Unified Coarse) if they are threaded into iron.
The wrench sizes you need are generally referred to “SAE” in the U.S. (Society of Automotive Engineers, who originally specified the wrench sizes) and “A/F” (Across Flats) in the U.K. and europe.
It’s useful to know what size bolts are used on your vehicle, and what wrenches fit them.
Most British built machines of that era are held together with 1/4”, 5/16” and 3/8” bolts. You will find them where you find 6, 8 and 10mm bolts now. The appropriate wrench sizes are 7/16”, 1/2” and 9/16”. You will use these a lot. Maybe a 3/8 wrench on a 3/16 bolt if your machine has them.
The bigger wrench sizes you might need are 5/8, 11/16, 3/4, 7/8, 15/16 and 1 1/8. These will cover you up to 3/4” bolts.
Smaller A/F sizes are only used on UNF “numbered series” fasteners, but…. Unified “numbered series” were not adopted in the U.K. (other than in the aerospace sector) so you hardly ever find these. What you may find are “BA” (British Association) fasteners instead. Even numbers are preferred, so a 2, 4 and 6 BA will do most of what you need.
If your tractor was built to a U.S. spec it could feature the smaller A/F fasteners, but that would be rare!
You may also find British Standard (Whitworth) sizes on your hydraulic fittings. Again, the U.K. never adopted Unified pipe thread (I’m not sure there was one) so used (and still uses, as does most of the world) BSP (British Standard Pipe) threads.
Hope that helps!
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