China Syndrome !!!!

[61BUBBLE348]

Hi Models, the broken rocker was an Intake, I am going to take a couple of spares with me just in case, when I get home I will install the original rockers.

Clyde, I know roll rockers are cast, but how common is it to cast a copy of a stamped rocker, apart from cost of press and dies to stamp them, I am no metallurgical engineer, but I can see how the arse has come out of the rocker, now I believe they are cast.

When I compared both rockers, new and original, 2 things struck me, 1 being the shape of the ball that the rocker pivots on, the original had a band of even wear approx 1/8" wide, with an equal wear spot on the rocker, 2 being the reproduction ball was of slightly different shape and did not fit the repro rocker as well as the original pair of items did, on inspection of the repo ball it had irregular wear marks.

This could be a contributing factor to the failure, increases pressure in the points of contact.

I am sure the guys that build the better engines may be able to chime in, knowing they all use rollers anyway, I have built the engine for street use and it probably will not see 6000 rpm.

Again this forum has enlightened me, what a terrific knowledge base.

thanks guys

 

[3483x2]

I had advertised some OEM Stamped Steel Elgin RK-406 Rockers. At the time none were available by Elgin. Somebody contacted me then about how Elgin had resumed production but from an overseas source with a stamped "43" on the inside of the rocker. He also mentioned DR409's being Chinese.

Yes friends... There is a difference!

 

[09Jud]

I used to put the ball or pivot in a drill press ,let it spin with some lapping compound and move the rocker as it moves in the engine till i saw a good patern lapped in, keep them in sets when you are done and clean them to remove the compound ,and use assembly lube.

 

[61BUBBLE348]

3483X2, The broken rocker was Elgin with the number 43 stamped.

cheers

 

[3483x2]

Wow... I heard the DR 409's (for $65 or so) were crap, but you'd think the Elgin's with the "43 stamp" and it's (so I was told) $127 market price would be a tad better. Now those turn out to be brittle cast as well.

Still have the Elgin OEM stamped steel set from the 80's I was only asking $100 for.

3483X2, The broken rocker was Elgin with the number 43 stamped.

cheers

 

[1960impala283]

Guaranteed unbreakable??? So do they send you another POS? .... Great I wish suppliers would be honest about the products they are selling. I would have gladly parted with more money when I was building. I tried to avoid anything made in China on my build.

 

[61BUBBLE348]

Just a quick update, changed out the rockers last night, no others were broken, which was comforting.

Made some interesting observations in relation to wear between the ball and rocker, in the majority the wear patterns were totally uneven and in a few cases one could assume the rockers had done 100,000 miles not 2000, as if the shape of the socket (rocker) was not designed to suit the machined ball. Not one of the 15 remaining had any sign of a good mating surface.

As others have said, when I build another W, I will either use the original stamped units or change to rollers.

To be fair on SC they may not be aware that the Elgin 43 rockers are substandard, or at least 1/16 are.

I gave the rockers the old tuning fork test, original GM had a slight ring when tapped with a spanner, the Elgins gave a dull thud.

cheers

 

[Don Jacks]

Well Grub,that just tells that they arent stamped steel,but cast steel.

 

[LMBRJQ 60]

I have a set of TRW 44015K what look like stamped steel rockers. I also ave the original rockers etc but the balls etc are not in the order that they were used. This stuff all arrived with the partially rebuilt engine. Question is what do i use?, 250HP original engine nothing flash. the new rockers have 43 stamped into them.
Cheers Steve

 

[johnnyrod]

I have had 2 rockers the stamped steel ones break the same way. Good thing I still have a used set of originals. Thank you for posting I thought I did something wrong when we built the engine.

 

[Don Jacks]

As a practical matter,on a stock engine with the soft [low seat pressure]valve springs,the mixed up rocker balls wont make any difference.I would coat the balls with a good "cam lube"and assemble the thing,you'll more than likely be fine.

 

[poison ivy]

dripper valve covers channel the oil to the rockers, and keep the springs cooler.riginal rockers work well, aftermarket rockers when dropped don't have that money ring. more like a klunk.. failure after only five minutes on dyno...