Improved rubber parts

[Declan_Burns]

The first test dust caps were moulded this afternoon. Still a few fine adjustments required but it looks very promising.


Regards
Declan


Dissected dust cap shows wall thickness to be OK
[frame][/frame]
Mould separated to reveal test cap[frame][/frame]
Removal from mould is very easy[frame][/frame]
Finished product top view[frame][/frame]
Finished product bottom view[frame][/frame]

We are getting there!

[bmcecosse]

Well done !

[don58van]

Yes. Well done.

Thanks for your ongoing innovative contributions to the Minor community.

Don

[amgrave]

Thanks for what you are doing, it's people like you that will help to keep our old motors on the road. I for one will buy the parts you help to manufacture to do my bit. Top marks fella.

[Declan_Burns]

New settings on the moulding machine.
Looking better!-today's results using different rubber grades. I am quite pleased so far.[frame][/frame]
The final will of course be dyed black[frame][/frame]

[aupickup]

looking good

[danielvoorwerk]

Great declan !

Will they be available begin 2016 ? (When plan rebuilding my trunnions ;-) ?

[Declan_Burns]

Daniel,
That is what we are aiming for. We intend to do a trial fit on Sunday on my mate's traveller in conjunction with a disc brake conversion.

Regards
Declan

[Cornishman]

Great work Declan, will buy them from you when available.

[Declan_Burns]

I have had to make some small changes to the trunnion seals. They fitted perfectly on the upper trunnion but were slightly too tall for the lower. Luckily my mate's trav had an original Mowog trunnion and seal. The Mowog seal is 13mm high. I had taken my measurements from repro trunnions and the seals vary between 14 and 15mm. When fitted to an original trunnion the seal squashes against the kingpin. I have changed the tooling back to 13mm so these will fit both the original and the repro trunnions. I have also increased the sealing contact are to match the Mowog seals. We also found that the repro lower trunnion screws in further than the original by approx. 3mm. It is important that there be a slight gap of approx. 1 ... 1.5mm between the top of the seal and the kingpin.
We will do some samples this week including the ring seals so if anybody wants to help test I could send a few free samples. We would also send out a (very limited) few samples of the rubber rocker cover and 1098cc tappet chest seals. We only have a few test samples left.

Regards
Declan

[M25VAN]

Happy to test the tappest cover seals if you would like Declan. Mine need replacing at the moment.

[philthehill]

Declan
There must be some variation in the overall height of the original MOWOG trunnion to swivel seals (Pt NO; ACA4012 (MOSS)) as the NOS ones I have and branded MOWOG are of 14.2mm overall height.
The I.D. (unfitted) of the MOWOG seal where it rubs on the swivel is 20mm and should rub on the machined part of the swivel above the threads.
The I.D. (unfitted) of the MOWOG seal where it fits over the bottom/top trunnion is 24.5mm.

The after market ones I also have are of 14.5mm (unfitted) overall height.
The I.D. (unfitted) of the seal where it rubs on the swivel is 19.5mm.
The I.D. (unfitted) of the seal where it fits over the bottom trunnion is 25.5mm.

Currently I have the genuine MOWOG seals fitted to my Minor and they fit very well. The swivel and trunnions fitted are also genuine MOWOG.
Unfortunately I do not have an after market swivel to compare the depth of swivel threads but of course the depth the swivel pin is able to be screwed into the bottom trunnion is dictated by the bottom trunnion pin as the pin has to be a free fit past the waisted threads of the swivel pin and not jam when the swivel is turned in either direction by the required amount.
If the MOWOG seal squashes/distorts against the swivel pin the swivel is screwed too far into the trunnion and should be unscrewed sufficient to un-squash/un-distort the seal - bearing in mind though that the bottom trunnion pin has to fit as above.
The seal on your mate's traveller - was it taken off the traveller and in a used state. If it was that may account for the difference in overall height between the after market ones and the MOWOG seal fitted.
Below is photo of MOWOG seal(s) fitted to my Minor.

Phil[frame][/frame]

[Declan_Burns]

Phil,
Your measurements of the Mowog seal tally exactly with ours, 20mm ID at the top and and 25.4mm at the bottom. My mate produced a set this afternoon and the ring seals also.
We did check the trunnion that it is screwed in as far as possible and then backed off so the trunnion can cope with the turning radius without binding. We did take photos. With the original Mowog seal there was a gap of about 1 ... 1.5mm between the top of the seal and machined part of the swivel above the threads.
With the repro seal it looked like the seal in your photo which is also up touching the machined part.
Perhaps there were several different Mowog seals over the production years.


Mowog seal Mowog trunnion[frame][/frame]
Mowog seal repro trunnion-trunnion screws up further[frame][/frame]
New seal repro trunnion[frame][/frame]
Photo of the new seal on the Mowog trunnion did not turn out but it was acceptable-not the case with the repro.

We have already changed the new seal back to the same dimension as the Mowog seal. I will pick them up tomorrow.

Regards
Declan

[bmcecosse]

Also worth checking inside the depths of the trunnions - in case there is some swarf compressed in there, limiting how far it can screw on the king pin!

[Declan_Burns]

Good point Roy
Regards
Declan

[philthehill]

Declan
Many thanks for the photos and info.
The trouble with re-pro parts these days is that the pre-manufacture process (i.e. getting the dimensions right) & quality control is not always as good as it should be.
The NOS spare genuine MOWOG bottom trunnions I have are all 66.2mm in overall length - not counting the convex Welch plug in the bottom.
The distance from the centre of the trunnion pin to the top of the trunnion should be 30mm.
The Welch plug can be knocked out and the threads completely cleaned - the Welch plug can then be refitted as if fitting a core plug.
The top cap of the top trunnion can also be removed as it just screws out and is retained by a couple of centre pops.
Phil

[Declan_Burns]

The lower trunnion dust cap has been corrected to 13mm as the original and the sealing collar also increased. We also did a small test batch of fulcrum pin seals which seem to be a nice snug fit. They are slightly thicker to give a larger sealing area.

Regards
Declan


We are nearly there![frame][/frame]

[don58van]

Brilliant!!!

[philthehill]

Delan
I will endorse Don's comment.
Interestingly the Marina/Ital trunnion pin seal (which uses the same size dia pin and thrust washers as the Minor) was increased in thickness to between 2.7mm / 3mm and had a woven finish on its outer surface. They also seem to have been made of much better material and so do not perish / fall apart so easily, the fit is much better also.
Keep up the good work.
As an aside the Marina/ital. trunnion pin is a much better finished pin than those fitted to Minors especially the after market ones and I always use those Marina/Ital pins when rebuilding the front suspension. Thankfully I have a few NOS spare ones on the shelf.
Phil

[simmitc]

Looks excellent When are they available to purchase?