Trunnion bolt nuts

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TOMO28B
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Trunnion bolt nuts

Post by TOMO28B »

Hi all, anyone know what size the nuts and pitch are each end of the top trunnion bolt, (the plain and castle nut),I only ask as I want to put nylok nuts on as an extra precaution. Many thanks.
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svenedin
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Re: Trunnion bolt nuts

Post by svenedin »

Maybe this is an unhelpful answer but it depends...

The top pivot pin was originally threaded BSF but the replacements now available are threaded UNF.

So it depends on whether your pivot pins are original or not. I cannot see why there is any advantage at all in using nylock nuts. On one end of the pin there's is a castle nut and split pin, at the other end there is a nut with a lock tab washer. A thread gauge is a very useful and cheap tool to have in the garage and then you can easily find out what you have fitted.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
philthehill
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Re: Trunnion bolt nuts

Post by philthehill »

There is no added benefit in having nylock nuts fitted to the top trunnion pins.
The rear nut and lock washer cannot be replaced with a nylock nut because of the two flats on the trunnion pin.
The two flats negate the nylock element and the nylock nut will come undone.
The front nut needs the castellated nut as there is not enough thread to accommodate a standard nylock nut.
The split pin ensures that the castellated nut does not come undone.
The factory fitted nuts cannot have additional nylock nuts fitted as there is not enough thread to hold the nylock nuts effectively.
My advice is to fit the factory nuts as standard and you will not have any problems. You do not need extra precautions.

Nylock nut have their place on a Minor and used in the right place can be very effective.

TOMO28B
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Re: Trunnion bolt nuts

Post by TOMO28B »

Thanks for the advice,I see your point on the flat ends of the bolts causing a problem with the nylok nuts,it never occurred to me.thanks again,
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