Yella Terra rocker arm failure

[tony-muscle]

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."

Well. That's the response I would expect from a reputable company. Too bad it too a bit long! The first guy probably had no idea what he was doing!

 

[basstrix]

I'm glad they are taking care of you. My question is, do you believe the rocker did not have the pushrod cup installed? I would think that it would have been obvious something was wrong on that rocker/valve position during install. In particular, the lifter preload step, for hydraulic, or lash step, if solid, would have exhibited strange behavior.

 

[INPete]

My engine builder is who assembled the long block. I didn't notice anything different on the rocker adjusters that looked concerning. However, I didn't pay that close attention to them. I just installed the valve covers, put on the intake, oil pump, oil pan, and installed the Holley Sniper 2 system. I was in a time crunch, so I had them assemble the long block to save me some time. It's hard to believe it wasn't there, but that could be the case. At least I wouldn't have to worry about the cup getting lodged somewhere or doing more extensive damage. Initial start up of engine, everything sounded normal and surprisingly ran great with the EFI system. Engine seemed to run strong even when the tick developed. But once I noticed it, I pulled the valve covers. I had made a few good hard runs before the ticking started.

 

[Cleveland Crush]

My engine builder is who assembled the long block. I didn't notice anything different on the rocker adjusters that looked concerning. However, I didn't pay that close attention to them. I just installed the valve covers, put on the intake, oil pump, oil pan, and installed the Holley Sniper 2 system. I was in a time crunch, so I had them assemble the long block to save me some time. It's hard to believe it wasn't there, but that could be the case. At least I wouldn't have to worry about the cup getting lodged somewhere or doing more extensive damage. Initial start up of engine, everything sounded normal and surprisingly ran great with the EFI system. Engine seemed to run strong even when the tick developed. But once I noticed it, I pulled the valve covers. I had made a few good hard runs before the ticking started.

Sure looks like the serrated pushrod cup was never factory installed. After running for a short time, the steel pushrod began to eat the soft Aluminum rocker seat, thus developing excess clearance and the resulting "clicking". Good news is nothing dropped into your engine.

 

[tony-muscle]

It is hard to trust any new components these days. I am also victim of this issue. I am more and more checking new items before installation, specially if they are critical components. However, the issue is how far to check. We can't check every little thing so we are bound to miss things and this is all made worse by the time crunch to get things completed. I know I have skipped some checking steps in favor of getting things done and understanding that it may backfire. Even if you check everything there is still the risk of failure due to material issues so it is almost impossible to be risk free within our time/money budgets.

 

[c9zx]

That is the response you should have gotten the first time. They hire business majors, or worse, a cousin to handle customer service. The YT set should sell easily. Chuck

 

[Hemikiller]

Exactly as Chuck said, that's how it should have been handled. It was quite obvious the seat was never installed. That's the difference between sales and engineering.

Somthing that applies now more than ever - "expect what you inspect"

 

[MAD IRISHMAN]

I've always had good service and product from both Harlan Sharp Rockers as well as Comp Cams. Just curious what the attraction might be for the YTs?

 

[basstrix]

I've always had good service and product from both Harlan Sharp Rockers as well as Comp Cams. Just curious what the attraction might be for the YTs?

YT is one of the few rockers that Jim Miller names as having proper geometry to follow his Mid Lift setup on both sides of the fulcrum. In other words, at mid lift, the valve stem will be at a right angle to moment arm between valve and trunnion as will the pushrod to trunnion moment arm. All of the valvetrain geometry has to be at nominal to achieve mid-lift on both sides, so not sure that's much of a benefit....so long as the rocker in use is fairly close to the mid-lift. Might be important to an NHRA champ, but to me, not so much.

They also offer a couple of versions that adjust at the pushrod cup. One of those can be used on stock rocker pedestals using the 5/16 bolt. Motorsport used to have the same style rocker (I was lucky enough to get a set) and Scorpion used to sell them, but I am only aware of YT's offering, presently.

 

[c9zx]

I've always had good service and product from both Harlan Sharp Rockers as well as Comp Cams. Just curious what the attraction might be for the YTs?

I bought a shaft mount set for my 330 CID SBF, 21 years ago, because they had a good reputation and were cheaper than T&D, THEN. Chuck

 

[MAD IRISHMAN]

I bought a shaft mount set for my 330 CID SBF, 21 years ago, because they had a good reputation and were cheaper than T&D, THEN. Chuck

I ran a set of T&D shaft rockers on my 351 SVO with Yates heads when I ran Super Gas back in the 90s. Cost a pretty penny but absolutely the right choice for that application. Larry Torres makes some mighty fine products!

 

[INPete]

I did get my set of Comp Cams 1830's on Saturday and installed them. Back on the road! Still waiting for the replacement rocker from YT, not sure if I'll put them away for a possible future build or decide to sell them. And yes, I did inspect the CC's before installation. They appeared to be perfectly fine. Next build, I'll have to make due diligence inspecting all parts and probably allow more time too.

 

[INPete]

Ok everybody, you’ll get a kick out of this! I received a package from YT. I noticed the invoice that they sent me 2 new rocker arms under warranty. Sounds great doesn’t it? Look at the pic of the unopened replacement rocker arms!

 

[Cleveland Crush]

Ok everybody, you’ll get a kick out of this! I received a package from YT. I noticed the invoice that they sent me 2 new rocker arms under warranty. Sounds great doesn’t it? Look at the pic of the unopened replacement rocker arms!

Good grief!!! No pushrod cups again??? Another example of inspect everything...twice

 

[INPete]

The left one has the cup that's properly crimped. The right one looks machined, but no cup in it. Just like my original.... I sent the pic to YT's engineering manager. His response: "I'm glad you received the arm & I'm speechless for the arm without the pushrod cup."

 

[Cleveland Crush]

The left one has the cup that's properly crimped. The right one looks machined, but no cup in it. Just like my original.... I sent the pic to YT's engineering manager. His response: "I'm glad you received the arm & I'm speechless for the arm without the pushrod cup."

The "good" new rocker in the Left photo appears to be lacking the cup serrations present on your good original rockers.

 

[c9zx]

Unbelievable! That has to be embarrassing for them. Chuck

 

[INPete]

The serrations are there, just hard to see in the pic. Hopefully this will open their eyes and have a little more due diligence in their "quality control". Surely, they will have someone go thru and check all of the rockers now. I couldn't imagine that I'm the only one that has had this issue, not once but twice in a row.