Trunnion stiffness?

[midget]

Recently received a new 8cwt king pin complete with top and bottom Trunnions.
I am concerned that the top one is very difficult to rotate from around halfway down. I questioned this with supplier, who assured me that this was in order. Have not fitted it yet as not ready.
Never bought a new Kingpin previously, so need advice please.

[philthehill]

There should be no stiffness in screwing the top trunnion down the top thread of the swivel pin.
The genuine NOS BMC 8cwt swivels fitted to my Minor allow the top trunnion to screw on/down as they should with no stiffness or play.
All I can suggest is that you try another top trunnion and see how that goes.
If that does not work return the swivel to the supplier.
Phil

[midget]

Thanks Phil, as I thought. Trouble is "they" are the only supplier that has a stock of these items.
As you undoubtedly know, the 8cwt pin uses an uprated steering arm which is much larger than the saloon/6cwt variant.
Would it be possible to have a saloon pin suitably modified for the larger arm?

This problem only came to light when preparing the suspension parts for blasting/cleaning and painting,I found that a previous owner had fitted a saloon pin/arm on one side only.

[philthehill]

Physically the 8cwt swivel pin is the same in all aspects to the saloon / 6cwt swivel pin except for the size of the steering arm hole in the swivel pin - therefore the saloon / 6cwt swivel can be modified by enlarging the steering arm hole and cutting a new slot for the woodruff key.
Any engineering firm worth its salt should be able to undertake the task.
Phil

[midget]

One step forward--one step back. As suggested I ran the old TOP trunnion down the thread and it was perfect.
However the old BOTTOM one was identical as the new one supplied--very tight.
To allay any fears, I did remove the bottom link before running thread
I'll see what the supplier has to say (I did flag this up to them when delivered) but veering towards modifying the saloon pin.
On that note, how the heck do you remove the steering arm? I have tried "tapping" the taper housing with no luck so far. Application of heat or use of a press?

[philthehill]

Apply moderate heat to the swivel in the area of the steering arm taper and hit the threaded end of the steering arm making sure that the nut is on the threads but slackened off a couple of turns.

[simmitc]

Apply Plus Gas or similar to the joint where the arm enters the swivel and leave to work its way in. Leave the nut on the arm and set it flush with the end of the arm to protect the thread. Apply moderate heat the the swivel around the arm. Crucially, support the swivel with blocks either side of the arm; and then single almighty blow with a 4lb clump hammer on the end of the arm/nut. It'd previously tried all the normal methods without success; but since supporting the swivel have found that a single blow always knocks the arm out.

[midget]

Thanks to you both for removal procedure which I completed today. Followed instructions, although I did use a bigger "spanner"!
Worked a treat and I will now pursue a machine shop in order to use the "original" swivel pin, and return faulty one to supplier.
Ran the old trunnions down the new one, which resulted in exactly the same problem. Ran the new trunnions down the saloon pin. and they were perfect, so obviously a faulty new pin

[philthehill]

Well done
Looking at your photo it appears that the swivel is a L/H unit.
Below is a link to a R/H 8cwt steering arm if your swivel is indeed a R/H unit.
http://www.morrisminorspares.com/front- ... ck-p830542
Though I suspect that you have the necessary 8cwt steering arm.
Phil

[midget]

Yes Phil. I rang All the suppliers (inc ESM) before I found a nearside arm.
Eventually found a second hand one from Ian Allen of Witchford.
BM were the only supplier of new 8 cwt swivels.

[midget]

More problems. Tried machine shop (Paynes of Oxford) but despite being a local efficient engineering workshop of long standing,has just declined to modify a saloon pin to accept the 8cwt arm, and could offer no alternative company that could do it.
Because it is a taper + woodruff key fit it is difficult to find the relevant tooling for the job, as can't be done on lathe or mill--apparently. Due to the formed shape of the arm, this also could not be tuned down to fit saloon pin! (that doesn't matter as I could simply fit saloon pin) but it would make it LOOK authentic.
Anyone have an engineering solution please?( or an 8cwt swivel pin )

[midget]

Problem solved--I think. Birmingham MM have one for me and have run their trunnions down the threads to check as I asked.

I will confirm upon arrival.