Con rods

[shaun]

Having removed con rods from block can anybody tell me if there 116 or 125 rods.The rods pictured have no marking and have 3/8 bolts thanks

[shaun]

Having checked all over for conrods identification , I still can't make out what they are someone out there must know , the closest I got was maybe farndon ?

[Famous Frank]

I don't know what they are either. Here are a few pics of some I have in the basement. Personally, I'd only use 125E rods. Anything else would have to go in my lawnmower.

116E's are marked 116E

125E are marked 125E

There is comparison pic attached.

And a pic that should explain why not to save money on connecting rods.

Frank

[Chancer]

They look like the Smethwick Drop Forgings rods that I bought for an all steel X/flow but turned out to be for a short stroke BDA although I would expect the marking to be SDF which means a homeless person here in France!

They look like uprated forged steel rods, get them crack tested though and dont allow an engine balancer to attack them with an angle grinder like some dick head did to mine

PS I also had some Farndon rods at one time so maybe its them that yours remind me of.

[Elan45]

Don't have any idea what rods you have, but I do notice the rod bolts look like normal socket head cap screws. I'm afraid I'd not want to use these at all, unless you really know what is what. I too, have one of those oh oh rods and the destroyed piston and block, probably because I believed the person I got the Carrillo rods from who told me the bolts were new.

Chancer, Do you still have the short stroke "BDA" rods? I've got to build a couple of BDH (1300) engines. Are they for narrow journals?

Roger

[shaun]

I think I'm finally getting there , measured the stroke today and got 77.6 mm so I guess it's got a crossflow crank and has had rods made to suit . The engine is a 1500 bored 40 so giving about 1700cc . I check the cap heads high tensile

[Chancer]

Don't have any idea what rods you have, but I do notice the rod bolts look like normal socket head cap screws. I'm afraid I'd not want to use these at all, unless you really know what is what. I too, have one of those oh oh rods and the destroyed piston and block, probably because I believed the person I got the Carrillo rods from who told me the bolts were new.

Chancer, Do you still have the short stroke "BDA" rods? I've got to build a couple of BDH (1300) engines. Are they for narrow journals?

Roger

No Roger they went years ago, I bought 3 and went looking without success for a 4th, in doing so I found out what they really were as opposed to what the seller told me they were, I was Young and naive, the proof that he knew was that years later I was contacted out of the blue by an unknown person who had been put on to me by the seller saying do you still have the three narrow journal short stroke BDA rods, I desperately need them!

[promotor]

I'm not sure what those rods are (although they look like GAF ones, or Martin) but they've definitely been shortened (which makes sense for a 1500 block with 1600 crank if using standard comp-height pistons) - the key is how thin the top part of the main bearing hole is : the thrust faces that contact the crankshaft aren't a constant thickness all the way around.

[Donels]

That's an interesting rod failure. It looks like a H section rod? All I ever learned about stress analysis suggests that H section rods are fundamentally the wrong way to go with I section rods being far better. But suppliers charge a fortune for them and people keep buying them. Is it BS over brains or am I missing something?

[nmauduit]

That's an interesting rod failure. It looks like a H section rod? All I ever learned about stress analysis suggests that H section rods are fundamentally the wrong way to go with I section rods being far better. But suppliers charge a fortune for them and people keep buying them. Is it BS over brains or am I missing something?

I thought that all things equal (...) H rods were stiffer, for higher torque/power/rev than conventional I rod ... then it appears there are a large number of fake H rods on the market (more than half according to some reputable manufacturers), not produced with the same materials, fabrication process (including temperature and other steps with an effect on material grain structure), possibly event tolerances... I've read somewhere mass production in India can be as low as at $10 a piece, leave a wide margin for packing and reselling abroad.

It would be interesting to know what brand was the faulty one, and if the fault has been traced to originate from the rod itself... Could it also be that these H rods (esp. cheap ones?) do not fail "gracefully" and immediately brake while I ones twist and knock first ?