Hi all , just purchased 2 conrods of flee bay , thinking they where a pare they have the same part number,one 67 -1160 ,R3R The other 67- 1160 ,R2R but one is 6mm longer centre than the other ? Any ideas ,thanks Nigel. :-\
send them back .
One is for an early crank.
Hi,
I thought the A10 rods were always the same length as it was only the big end journal that changed whereas the early A7 had a longer stroke?
If these are small journal rods you may have one for an A10 and one for an A7 although I think later A7s may have had large journal cranks.
Dave.
You are right. The numbers do come up as A10.
Hi,
It would be interesting to see a photo if possible.
Dave.
I'm not sure how to up load photos, sorry
These are the Rods .
Good morning,
It looks like you have small journal rod on the left and a large journal rod on the right. If you sit one on the other with the small ends lined up the difference will be more obvious. The joint face for the cap should also line up. The stroke is the same with the difference being in the big end journal size.
What crank have you got?
It may be possible to have the small journal made bigger but I would ask the vendor to supply the correct one or send them back and find another pair.
Dave.
The rod end caps were changed when the castelated nuts were replaced with self locking.
I think the rod on the right of the photo is the earlier type.
The service sheet shows the change but not the full detail.
The photo shows rods taken from a 1961 engine.
Hi,
Roughly measuring Glover's photo the left rod seems to have a smaller big end. 56mm and 62mm respectively. What is the actual difference between small and large journal?
Dave.
I do not have a crank yet , bought a really good large journal
One and guess what it got lost in the post , Her mess,
Both big end eyes are the same size , if you lay one on top of the other joint faces line up , but little end eye on the older one is 4 mm further from bigend joint 🤪🤪🤪.
Hi,
Unless Julian can come up with an answer I would say that one is not an A10 rod and I am now confused.
Dave.
Glovers rods are certainly large journal. Small journal rods have forging number 67 270 on them.
Best way to compare the 2 rods is to insert a gudgeon pin through the small ends then the split in the rods should line up.
The distance between rod bearing centres is given as 6.467 - 6.467 inches. Not the 6.5 inch dimension some of the new billet rods have been made to.
If the dimensions vary by 4 mm then at least one of the rods is scrap.
Little ends lined up , as you can see there is a fair discrepancy, surely not stretched that much !
I think to use those rods is risk. With what has been seen and no known history I would not let them near my A10 engine.
It also looks like they are both drilled with oil holes, only the drive side rod was so drilled.
If a rod had had such a hard life so as to cause the rod to stretch there would surly be noticeable ovality of the big end and a very worn small end. I know it would only be by a small amount but do the number and letters how any sign of distortion when compared.
But, as Julian says, best not to take the chance and feel sorry for whoever has the other odd pair.
Dave.