Trumpet to transmission housing nuts

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Bensdexta
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Trumpet to transmission housing nuts

Post by Bensdexta »

My tractor appears to have a mixture of studs and bolts securing the trumpets to the transmission housing (13 on each side), with assorted nuts, some self-locking.

Some of the nuts are badly rusted and need replacing. Think I have an oil leak from here as a result. :cry:

Can someone give me the sizes of the studs/nuts, as the parts list doesn't seem very clear on this.

Can I just replace the nuts one by one, without fear of altering any pre-loads?

TIA
Bensdexta - 1961 working for a living!

Bensdexta
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Re: Trumpet to transmission housing nuts

Post by Bensdexta »

Managed to get a stud out.

It is 7/16" dia, 1.7/8" long with flat bottom and slightly rounded top. The housing end has a UNC thread 7/8" long. The nut end has a UNF thread 3/4" long.

Nuts appear to be 11/16" AF.

Am I correct in thinking that there should be 13 such studs on each housing? And that originally the UNF nuts were metal self locking type (with no spring washers)?

I guess that now replacements will need to have springs under them? According to the manual, nuts should be torqued to 50ft.lbs (68Nm)

Can anyone confirm ?

TIA
Bensdexta - 1961 working for a living!

Tubal Cain
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Re: Trumpet to transmission housing nuts

Post by Tubal Cain »

You can use Nyloc nuts either with or without a plain washer.

If you change them one at a time you will not disturb anything.

Gerald

Bensdexta
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Re: Trumpet to transmission housing nuts

Post by Bensdexta »

Many thanks, Gerald
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Tubal Cain
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Re: Trumpet to transmission housing nuts

Post by Tubal Cain »

Ben,
Your post prompted me to do some research, I searched the internet and found that the nuts fitted to my tractor are known as "Philidas" nuts. They are available on Ebay but are not cheap.

I also checked the parts manual and under Fig 9 Differential Housing, are listed 26 x 7/16" x 14 bolts, axle housing to shaft housing, which suggests that bolts and not studs were fitted!

Gerald

Bensdexta
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Re: Trumpet to transmission housing nuts

Post by Bensdexta »

I suspect that may be an error in the entry in the Parts List, because in Fig 7 Rear Axle and Differential, there is reference to two types of nuts (26 off). I suspect someone had another sleepy day a Dagenham, as the Workshop Manual certainly refers to studs.

Why would self-locking nuts be used here and apparently nowhere else on the tractor - aesthetics perhaps? :scratchhead:
Bensdexta - 1961 working for a living!

Tubal Cain
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Re: Trumpet to transmission housing nuts

Post by Tubal Cain »

In my parts manual it states that from the O1/59 the nuts changed from 7/16 x 20 hex to 1/2 x 20 self locking. However I couldn't find any mention regarding the studs which were fitted!

Gerald
Last edited by Tubal Cain on Mon Aug 26, 2013 7:41 pm, edited 1 time in total.

Bensdexta
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Re: Trumpet to transmission housing nuts

Post by Bensdexta »

Tubal Cain wrote:In my parts manual it states that from the O1/59 the nuts changed from 7/15 x 20 hex to 1/2 x 20 self locking. However I couldn't find any mention regarding the studs which were fitted!
Quite!
The nuts on my diff are 7/16" dia UNF, 11/16"AF, neither of above!
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Johnmcm
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Re: Trumpet to transmission housing nuts

Post by Johnmcm »

Sorry to resurrect this thread.
Does anyone know where to find these studs and nuts?
Having taken off a redundent auto hitch top section (the rest was missing) I am in need of 3 each side.

Many thanks
John

Bensdexta
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Re: Trumpet to transmission housing nuts

Post by Bensdexta »

I got some from www.mayhilltractors.com/
Very helpful.
I believe they are same as Ferguson. :wink:
Bensdexta - 1961 working for a living!

Johnmcm
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Re: Trumpet to transmission housing nuts

Post by Johnmcm »

Cool, thanks Ben :D

Bensdexta
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Re: Trumpet to transmission housing nuts

Post by Bensdexta »

Johnmcm wrote:Cool, thanks Ben :D
Forgot to say phone them up as they're second hand parts. :wink:
Bensdexta - 1961 working for a living!

tom lad
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Re: Trumpet to transmission housing nuts

Post by tom lad »

A T engineering at brock , nr. Preston are HIGHLY recommended by me , very rare they don't have the nuts/ bolts for me .
do n't think they stock studs tho tbh

01995 640058
they love farmers going in with rusty /stinky crap wanting a new shiny bolt :beer:
Some mornings I wake up grumpy, but most mornings I let her sleep in.

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