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[Mike H]

Hi All

I have a 1947 E27N which has never been drilled or threaded on the rear of the tractor to accept the top link bracket, can anyone please advise on the drill and taps sizes to be used to do the job ?
Thanks in advance
Best regards

Mike H

[super6954]

Hi Mike
Not many of the E27Ns have been drilled and that bracket fitted. I have seen a few from Australia that have the new style bracket mounted on the flange, bolted Like the new style major has. all the other e27N tractors with hyds I have seen had a 3 piece bracket it is 2 cast brackets one either side of the axle center casting,with bolts through the axle tubes into the trans casting. and then an angle iron bracket across the 2 held with 4 bolts and nuts. This then has the top link brackets welded to it. If you are restoring the tractor is the cast bracket bolted to the flange correct for your country . or are you going to inadvertently screw up a restoration . if it's a working tractor that won't be restored I can see no problem drilling and tapping.
not sure what the bolt size is right now but will go look at a tractor and get back later .
Regards Robert

[Mike H]

hi Robert

Thanks for the reply, I have the plate but was just using it for spacing the holes as I intend to fit a Cooke wood winch on the back of the tractor but the bolt size would be the same as when the top link plate was fitted.
Cheers

Mike H

[super6954]

Hi Mike
Thanks for the explanation It's better to check what a guys at sometimes, seen a good few tractors screwed up with incorrect parts during restorations i just pulled a bolt from a power major bracket. it is a 5/8" coarse thread and the bolt is 1 3/4" long. Checked it against the threaded holes in my E27N lower down and it's the same threads. so that should be what you want .
I guess your gonna need a pretty good sized hand held drill ,and for lord Murphy's sake don't break the tap off in the hole . Got a super here somebody did that to and it's gonna be a pig to fix that mess .
Regards Robert

[oehrick]

For largish holes and taps I have over the years converted a number of carpenters ratchet braces from the appalling 2 jaw chucks they come with to a 3 jaw, initially Jacobs and more recently the keyless types, these will hold a twist drill or tap nicely (over 1/2" you might need to turn the shanks down a bit to fit) You'd be amazed at how quickly you can put big 'oles in or drive taps (where the ratchet helps as you can back the taps out frequently) slow speed and lots of end pressure !

You may wonder why I've converted a number of these when one would last a chap a lifetime............

We had an electrical proximity switch go obsolete on us years ago and found the only available replacements had a larger thread fixing - M22 fine IIRC - it was the first item fitted to a hollow mainframe through which the wiring ran, rest of machine assembled on top. How do you drill and re-tap the hole without loosing the wires in the frame ???
The designer who spec'd the replacement was at least bright enough to see that this was going to cost a fortune as we had about 120 of them spread world-wide, (the lads in the workshop took 3 days to do the first upgrade - by stripping the machine down after fishing for the lost wires failed)

I picked up the 'kit' and was despatched to a relatively local plant to loosen up everything then come back and pick up a couple of fitters to help with the heavy lifting etc. Sat amidst a sea of thawing turkey sawdust (Yup Brian it was one of Bernards - he ended up with about 80 of them in his empire) one of those rare flashes of inspiration hit, the wires would only get lost if stuffed back through the hole to drill and tap, there was plenty of room for them in both drill and tap flutes if slowly turned a rev or two at a time, the brace was brought into action and the job finished in under an hour.

It was several years before I let on my secret method and as a result ended up as conversion specialist for this job, about 40 in the UK, Europe & Scandinavia, 20 in NZ, half a dozen in Oz and the rest in the US & Canada, the one I desperately wanted to go to was on Vanuatu but the factory burned down before theirs failed

Everywhere the modified brace was seen it was admired, where there was a plant engineer who had gone out of their way to help I left it with them and made a new one when I got home.

Sorry for the ramble but a very useful tool in my kit, as are the old boilermaker / blacksmiths ratchet drills and stands if you are not looking for high precision

[Mike H]

Hi Robert

Thanks for taking the time on this, I have a magnetic drilling machine which should hold on with a little assistance I will now go and source a 17/32" fluted mill and tap it out for 5/8" UNC.
Fantastic having the Forum to get assistance when needed !

cheers

Mike H

[Mike H]

Hi oehrick

Thanks for the reply, great information thank you, I will try with the magnetic drilling machine but if that cannot hold on at the angle I will be looking for a brace !
Thanks again

Mike H

[super6954]

Hi Robert

Thanks for taking the time on this, I have a magnetic drilling machine which should hold on with a little assistance I will now go and source a 17/32" fluted mill and tap it out for 5/8" UNC.
Fantastic having the Forum to get assistance when needed !

cheers

Mike H

Hi Mike
Not a problem, sounds like you have a good bit of knowledge there and a few useful tools laying around . I would like one of those drills but anything like that here in canada is hard to find used or very expensive new. This then makes owner ship very expensive, for occasional use . The machine shops are getting above themselves as "specalists" and Charging way to much now also. This kinda heavily restricts what a guy can afford to do for projects/ fun round here, and what also becomes uneconomical to repair for farming use also .
Regards Robert

[Mike H]

Hi Robert

The mag drill came for free, I guess I was lucky to be in the right place at the right time as it was about to be thrown in the scrap pile, it's only crime ? it was no further use to the people who owned it, now has it's own space on a shelf and gets a good clean after use.

regards

Mike H

[oehrick]

Hi Mike

If you've one of those magnetic drill jobs even better - even if you have to bolt or chain a temporary plate or girder on to avoid the angle

Fingers crossed

Rick