G12CSR pushrod

[ksj_LAPSED]

I was checking a very noisy tappet yesterday & found that an exhaust pushrod had broken { the engine still ran } in the middle . If I can't get a new one has anybody ever made one ? what grade of aluminium ? does it have to be hollow or would solid be ok ?

[SPRIDDLER]

Surely it can't be difficult to locate a s/h one?
My first port of call would be Steve at AMC Classic Spares, then Club spares, Russell Motors, eBay......
As an absolute last resort I'd 'repair' it at the break by Aralditeing a say, a 40mm long close fitting pin inside, or a similar length sleeve on the outside.
Hollow alloy tube (HE9 or similar) is available from model maker stockholders. The o.d. is the critical dimension in order to be a close fit for the end pieces.
Although it's purely a guess I wouldn't use solid rod since it will be marginally heavier than hollow and could accelerate wear on the tappet foot over a long period.

....but I'm pretty sure that s/h ones aren't rare.

Edited in view of Bob's personal experience.

[zwarts]

Keith, I make my own twin pushrods and have done for a good many years. I use HE30 solid rod - it's widely available and is perfectly adequate for the job. 5/16 dia rod will need turning down slightly at each end so that the end caps are a snug push-fit. The steel end caps can be re-used from the old rods and fixed to the replacements using Loctite grade 648. I've never had any come loose and that includes those on my racing outfit engine which does live rather a hard life. If you prefer hollow push rods, get a set of VW Beetle pushrods from the breakers - they are the right dia. and more than long enough. There are plenty of secondhand AMC pushrods around but they usually show wear at the point of contact with the cylinder head joint. The steel mesh reinforced head gaskets can produce alarming wear at this point if they encroach on the barrel pushrod drillings.
Cheers, Bob.

[Rob Harknett]

Not so long ago I got a new set of G12CSR push rods from club spares. Have you checked if they have what you want?

[ksj_LAPSED]

thanks chaps just the info I needed club spares are out of stock , I did think of squaring the ends and making a stepped sleeve but if none of the dealers have one I might go down the ally rod route

[39speedtwin]

Just ask Roy.