Radial engine rods

[AMCKen]

I was at a local engine shop the other day and spotted this setup on the floor. The owner says someone brought it in as a decoration for the shop, but it was never put up, and he gave it to me. Curious as to what engine they may be from. 7 cylinders (obviously). Master rod big end is 3 5/8 inches in diameter and 3 1/4 inches wide. Master rod is 14 inches centre to centre. Slave rods are 11 inches (c-c) with the small ends 1 1/2 inches diameter and 1 3/4 inches wide. No markings of any sort that I can see - no manufacturer, no part numbers, no serial numbers.

 

[Crimea_River]

Given that you're 3 hours north of me, I'm going to throw out a guess here. Avro Anson wrecks were a dime a dozen here in Alberta and it's possible that your rods come from a Jacobs L6-MB engine that powered Ansons that were built in Canada. UK built Ansons were powered by the similar Arnstrong Siddley Cheetah and, since there were British built machines over here, it may be form one of those as well.

We have a few Jacobs and a Cheetah in our museum in Nanton and I'll see if I can verify my guess next time I'm there. One of the Jacobs is being overhauled and I might be able to see the rods.

 

[bobm4360]

Neither the Jacobs R-755 nor the Continental R-670 use a spider to retain the knuckle pins. HTH.

 

[dogsbody]

So this was just laying around an Edmonton engine shop? Lucky you!

Chris, from a bit to the northeast of you.

 

[AMCKen]

Noticed the foxtail seed after I had uploaded the pics. Oh, I see the part you mean - the 7 legged spider that the bolts come through.

Neither the Jacobs R-755 nor the Continental R-670 use a spider to retain the knuckle pins. HTH.

 

[WJPearce]

To me, the master rod looks like it is from Wright Aeronautical. Given the size, I would think it is from one of their larger stroke engines (not Whirlwind). Since it is a seven-cylinder, my guess would be either an R-1300 or R-2600. Attached is a drawing of R-2600 connecting rods, and the R-1300 was basically half an R-2600. I think the drawing is very similar to the mystery rod.

Since only 3,545 R-1300 Cyclone 7 engines were built, and 85,374 R-2600 cyclone 14 engines were built (each with two master rods), the odds favor it being from an R-2600. Of course, I could be completely wrong.

 

[Crimea_River]

I was mistaken. The radial being overhauled in Nanton is an R-1340 so no joy.

 

[AMCKen]

The Wright looks possible. Now all we need are some dimension numbers. Thanks