Mystery Lightweight con rod

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clanger9
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Mystery Lightweight con rod

Post by clanger9 »

On stripping down my late-model CSR engine, I noticed that the con rod is marked with the part number "049998" on one side and "EN351" on the other.

I presume from the EN351 marking that this is a forged steel con rod. I can't find that part number in any of the supplemental parts lists. Can anyone shed any light on it? It looks much more substantial than a normal Lightweight con rod. I'm guessing this was a standard fitment for later CSRs (with the steel flywheels).
1989 Moto Morini Dart 350
1993 Ducati 750SS
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Ozmadman
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Re: Mystery Lightweight con rod

Post by Ozmadman »

clanger9 wrote:On stripping down my late-model CSR engine, I noticed that the con rod is marked with the part number "049998" on one side and "EN351" on the other.

I presume from the EN351 marking that this is a forged steel con rod. I can't find that part number in any of the supplemental parts lists. Can anyone shed any light on it? It looks much more substantial than a normal Lightweight con rod. I'm guessing this was a standard fitment for later CSRs (with the steel flywheels).
Maybe it is just a casting number? sometimes a few numbers different to the part number. It should be more substantial to the normal 250 rods as the big end bearing was uprated from the normal 250 which was prone to failure even on the standard engine. I am not sure but i think the CSR big end bearing is the same as the 350 engine bearing.
Paul
1960 Model 8
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clanger9
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Joined: Sat Jun 20, 2015 9:38 am
Location: Chester, UK

Re: Mystery Lightweight con rod

Post by clanger9 »

Ah, my bad: I think the stamped part number is "042226".
Still none the wiser, as this part doesn't seem to be listed anywhere but at least it looks like a normal AMC part number...
1989 Moto Morini Dart 350
1993 Ducati 750SS
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Stuoyb
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Re: Mystery Lightweight con rod

Post by Stuoyb »

That is the casting number which may be used to make more than one part.
The finished conn rod is a different part no. (As shown in the parts list)
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