Club Rods are tight

[adrian.hannam]

John that was a similar but different discussion. Someone else was recently offered a discounted set via the Club Spares Organiser which the big end eyes were not honed to spec. http://forum.arielownersmcc.com/viewt ... =4&t=10344
My rods came from Draganfly at full price. I have had them on my shelf for a year or so. If mine were the same it was not disclosed to me, and I did not get a discount. I prefer to give Draganfly the benefit of the doubt, their observation is reasonable I and take responsibility for my decision to use the hone. There are some numbers on the back of the shells but I didn't take note of them. I think I will take a rod off to do some research. What the hey, I've already had them on and off about 12x4 times.

[david.anderson]

John said
if you fit 002 shims between cap and rod both sides, then bore the tunnel 002 oversize, you get a free(er) fit of the bearing at the parting line...
But that is not possible with club rods as the rod and end cap mating surfaces are corrugated. (or at least the original batch which my rods come from were).
With regards to the shells being from a car, I am not aware of any that fit or are very close. It was however years ago that I checked. But there was a BSA stationary engine that used the same shells as the square 4. Square 4 shells were not available and it was common knowledge here regarding the BSA stationary engine. I purchased a set of the BSA shells from Burglars and Stealers (Burling and Simmons BSA dealers) years ago and they fitted perfectly. John Shanks can probably tell you which stationary engine the shells came from as it was on his advice that I purchased the shells.
If the rods are undersized it is an easy job to have them honed to fit. It is common for Holden commodores to spin the slipper shells on a poorly maintained engine. The standard fix is to mill a little off the mating surface (close the rod) and then hone to size.
David

[john.whiting]

The only common BSA stationary motor of the sixties was the 420cc wet sump one ,so that would have been it....As mentioned ,sizing the tunnel is standard practice in a engine reco shop....Sunnen make a proper pin fitting and rod tunnel sizing machine that does nothing else ,and take s up little space on a benchtop.......Ive repurposed shells for obsolete diesels ,the only critical factor is wall thickness.....the rest is easily trimmed .....Incidentally ,I assume all the S4 fixers know that all shells should be opend out a bit ,so they snap into position in the rod.Never fit a shell which is not tightly held in the half seat ,but open it out.

[adrian.hannam]

You guys are good. The shells in use have a number on them: W1426-002. I looked in the box of spares that came with the project and there was little box with 8 used shells in it. Also a note on a torn envelope which I can't quite make out the last bit i think it says "standard on original shafts". I am not a detective, but the W number does not correlate with the number on the box.The box has a scribble through the part number and .002 added. The date on the box is 21 Jan 1969. It would be an assumption (maybe a good one) that these are the W bearings. All a bit moot now, I'm going to move on. Next challenge - fitting the block.

[john.bebb]

Hi Peoples,
with reference to the subject that "Club rods may be tight" - I here refer solely to the BIG-ends
I recently obtained a Club set from Bruce (at reduced price) 'cos the big-end eyes were undersized & will require honing...
Bruce implied that there may be other sets out with similar undersize big-end eyes...

[paul.ptak]

What should the dimension of the big end be without a bearing shell?

I'm having two sets (8 rods) made by the manufacturer and it sounds like the blueprints they have show two different sizes for the big end.

Paul

[john.bebb]

Hi Paul, et al; -

"What should the dimension of the big end be without a bearing shell?"

Herewith copy/paste from Draganfly
https://www.draganfly.co.uk/ariel/4-str ... nd-1937-58

(para #5): - Standard size of the big end crank journal is 1.375”; the timing side journal is 1.250”; con-rod big end eye diameter is 1.5002/1.5007”

It is NOT stated but I assume the two sizes for the eye as quoted above to be min & max tolerance for ovality.

Cheers, John Bebb

[paul.ptak]

Hi Paul, et al; -

"What should the dimension of the big end be without a bearing shell?"

Herewith copy/paste from Draganfly
https://www.draganfly.co.uk/ariel/4-str ... nd-1937-58

(para #5): - Standard size of the big end crank journal is 1.375”; the timing side journal is 1.250”; con-rod big end eye diameter is 1.5002/1.5007”

It is NOT stated but I assume the two sizes for the eye as quoted above to be min & max tolerance for ovality.

Cheers, John Bebb

Thanks John.

I did see that info on the Draganfly site and was looking for a confirmation as the manufacturer had some conflicting information on their drawings.

I talked with the manufacturer today and the spec they have on record is 1.4999 - 1.5004. I'm going in with the idea that the big end and small end can be honed to fit. Fortunately I have a shop near me that specializes in building race engines so having a pro do the honing on specialized machines is easy for me to have done.

I know the small ends will need to be honed as I have two sets of pistons from different manufacturers and the pins are larger than the factory dimensions, and different between manufacturers, so a visit to the shop is going to happen.

Rods are supposed to be completed today, so I should have them late this week or early next.

Paul

[john.whiting]

There is no practical difference in the dimensions quoted .......dont forget ,when dimensions of ally components. are in tenths ,then a temperature must also be stated. Furthermore ,any one trying to fit shells to a worn journal ,should construct a cast iron lapping tool to round up and correct taper in the journal ,no matter how slight.

[adrian.hannam]

For my new rods, measuring the big ends without shells, all IDs were smaller than 1.5". The smallest one I measured was 38.025mm = 1.497"
The old rods all measured 38.11mm +/- 0.02mm, = 1.5" +/- 0.0005.
I only measured up-down and I am pretty heavy handed with a mic.