Yella Terra rocker arm failure

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Anyone else seen this? I developed what sounded to be a lifter tick after about 300 miles on a fresh rebuild. So decided to pull valve covers and check and adjust valves. I am running a hydraulic roller cam. Once the valve covers were off, I just hand checked for any loose rockers. Immediately number 5 intake rocker was very loose. Pulled the rocker to inspect it and noticed the cup where the pushrod sits is missing. Decided to pull all of the rockers to check them all. 15 rockers have crimp marks on the cups. The one missing does not. Appears to me that this is a manufacturers issue. Here are a couple of pics
 

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I had an Aluminum rocker that did not have it's factory crimp on the roller tip axle. Not Yella Terra but Crower. Fortunately noticed the pin pulling out during a routine valve lash. Scary, but these quality control mishaps can happen to any brand, some more then others!!! As stated by Tony-contact YT, you have a free replacement rocker coming your way.
 
I've sent them an email last night and also called them, still waiting for a reply. I know the warranty is 12 months. I purchased them mid April last year when I started the build, just everything took longer than expected with everything else on back order. So I'm literally 2 weeks past the "12 months", we'll see if they stand behind their product. Otherwise, I'll probably order a set of Comp Cam 1830's since they are in stock and seems to have good reviews.
 
The YT parts are of great quality. I have a shaft mount set on a 330 CID Windsor in the Cobra for the last 23 years without a problem. I would contact them with the pictures attached. I'd bet they will make it right. The question is, where is the cup? It is too big to cause much of a problem however, it would be good to retrieve it for display on the "wall of failed parts"display. I hope all works out well. Chuck
 
That's too bad, YT is supposed to be top notch. Hope they take care of you. I'd also be very nervous about finding that missing cup. I've seen lifter circlips pulled through the oil pickup and lock up the pump.
 
I think the cup is too large to get sucked up thru the screen. I'm just hoping it settles into a corner somewhere and lives there. I'll drain the oil once I get the new rockers put back on and try to fish around with a bendable magnet and hopefully find it. I didn't see it lodged anywhere in the head castings and don't see it in the oil drain back either. Sent a follow up email last night, hopefully I'll get a response by Monday.
 
I think the cup is too large to get sucked up thru the screen. I'm just hoping it settles into a corner somewhere and lives there. I'll drain the oil once I get the new rockers put back on and try to fish around with a bendable magnet and hopefully find it. I didn't see it lodged anywhere in the head castings and don't see it in the oil drain back either. Sent a follow up email last night, hopefully I'll get a response by Monday.
A method you can try is to run a good magnet along the bottom of the oil pan towards the drain plug when draining the oil, assuming the piece is magnetic. If the piece is somewhere in the bottom of the pan you may be able to "pick" it with the magnet and drain it as you move the magnet toward the drain plug. Don't ask how I know this could work!
 
I think the cup is too large to get sucked up thru the screen. I'm just hoping it settles into a corner somewhere and lives there. I'll drain the oil once I get the new rockers put back on and try to fish around with a bendable magnet and hopefully find it. I didn't see it lodged anywhere in the head castings and don't see it in the oil drain back either. Sent a follow up email last night, hopefully I'll get a response by Monday.
Strange things can happen, glad you're confident it won't go through the screen.

If you're not able to fish it out, I suggest finding a magnetic drain plug....rare earth magnet, if available.
 
It looks like the upper rocker had a different style of pushrod seat installed, without the splines like the lower. If it was, there would be witness marks in the aluminum body. I'm curious what YT has to say about this issue.

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Still have not received any response from them. I sent my original email Thursday night and also called and spoke to someone. I sent a follow up email Friday night. I know they are 12-13 hours ahead, so this evening should be Monday morning for them. Hopefully I will hear something by Monday or Tuesday, otherwise I will move on and get the Comp Cams rocker set.
 
Here's the response from YT if anyone is interested:

Hi Peter,
Apologies for the delay on this, it’s been handed back to me to communicate with you.
The warranty has expired on the rockers. We do actually have a single arm and hardware available.
Can you send me your address and I will prepare a quote for you?
Thanks,
Richard Annable | Ecommerce Coordinator
Yella Terra

Needless to say, I am very disappointed with their response. Of course, I had to call again last night to check on an update. Seems like my "case" was passed around. Regardless, I will probably purchase a single rocker and put the entire set up for sale. I will be purchasing a Comp Cam set with life time warranty and made in USA. This definitely affects any future purchases that I had in mind for any performance products.
 
Wow, that's pathetic! I get that the warranty period has expired, but this is not a worn out roller tip or trunnion bearing...this looks like a manufacturing defect to me. I won't be recommending their product again. If you're up for the possibility of a verbal beating, you might consider posting on the cleveland facebook group. There's a small chance it would get back to YT and possibly get you a little more help from them (like a free rocker). I suspect they'll offer you a replacement at cost, as things are.
 
Here's the response from YT if anyone is interested:

Hi Peter,
Apologies for the delay on this, it’s been handed back to me to communicate with you.
The warranty has expired on the rockers. We do actually have a single arm and hardware available.
Can you send me your address and I will prepare a quote for you?
Thanks,
Richard Annable | Ecommerce Coordinator
Yella Terra

Needless to say, I am very disappointed with their response. Of course, I had to call again last night to check on an update. Seems like my "case" was passed around. Regardless, I will probably purchase a single rocker and put the entire set up for sale. I will be purchasing a Comp Cam set with life time warranty and made in USA. This definitely affects any future purchases that I had in mind for any performance products.
Wow. I have YT rockers at the top of the list. This is disappointing. I am sure you already did, but I will reply stating your disappointment and the fact that this is clearly a manufacturing issue. I will say that a company of their reputation should take responsibility for their own manufacturing defect (key word to use). If not fixed then I will definitely post in the Cleveland Facebook group since it is in that group where YT is talked about like the best.
 
I am glad this topic was posted, to include the manufacturer's response. Guess who is not going to be on my short list for valve train components when I begin to do an engine build? Burning a fellow enthusiast is just as bad as burning me. Sure, warranty expired. But, it sure looks like a manufacturing defect caused the grief. Had it been me I would have backed my product despite any technicality re: warranty period. A failure is a failure.
 
So I replied to their email, and got another response fairly quickly this time:

Hi Peter,
Expired may have been the wrong word on my behalf. I was advised the warranty did not cover your situation, but I will send your reply to my manager to see what his input is.
Thanks,
Richard | E-commerce Coordinator
Yella Terra | store.yellaterra.com.au

Just being transparent about this situation, so will let everyone know how this plays out. Regardless, I've purchased my Comp Cams set and those will be installed this weekend. I'm more disappointed that I had to contact them multiple times in different ways to get any response. More than likely, I will also post this on the FB Cleveland group too. Just waiting to see what the final outcome is.
 
So after a few back and forth emails last night and my situation given to the engineering manager, they will be shipping me a replacement rocker. This was his response:

"Well, that’s simple ….. it’s an assembly failure due to a missing cup.
This is obvious that the cup is missing & this rocker should never have passed inspection & so I’m extremely sorry that you’ve received the response you did."

"Putting aside the fact that we’ve missed the cup being installed altogether; on the initial installation it would have seemed to be very similar to the res of them & then as the engine fired up it shows that the pushrod has basically made an imprint into the aluminium & therefore an increase length & thus too much clearance causing the tapping noise … it all makes sense."

"Again, I apologize for the missing cup & even more so the unfortunate & incorrect response you received."
"YT 5006 set go to the US all the time & many time with high performance head packages so you should be fine."
 
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