flintwrench69

iTrader: (11)

Started the car up today, noticed some unusual ticking. It got louder & finally went away but the engine misses. So pulled the valve covers & found cyl 6 intake rocker broke. I know this is a common problem with these rockers but they held up great for the 3 years & 22,000 miles I put on them. I bought them from Scoggin Dickey, is there any kind of warranty on these & how do I go about replacing the broken rocker? Pics

badazz81z28

iTrader: (6)

Looks like metal fatigue...Kind of explains why some parts are intended for race only and not your daily driver.

1slowbusa

iTrader: (8)

That sucks. I have yells terras as well. I don't know about the warranty. Keep us updated on the outcome.

JakeFusion

iTrader: (7)

Those are the new ones that were supposed to alleviate the broken rocker arm problem. You know that because of the offset 1.7 stamped on it.

The problem is it's an aluminum rocker arm. I wouldn't do aluminum in a car that sees lots of miles.

RonSSNova

iTrader: (3)

So much for the upgrade.
What open spring pressure were you running?

I have the old style, lots of drag strip passes, but only about 2k miles.....

Ron

JakeFusion

iTrader: (7)

That would be good to know. Cam lobes used, springs, valves. Hell what lifters are you using.

gouldy

That's not entirely correct. The newest revision has the 1.7 stamped on the right hand side not the left.

vettenuts

iTrader: (4)

The newer design is supposed to be stronger. Unfortunately aluminum has a mush lower fatigue life than steel and these rockers I have always viewed as expendable. Not sure if you have done springs yet but my plan was to do the rockers with the springs, now I am not sure they will go that long.

dr_whigham

iTrader: (49)

I've seen way too many of these getting broken as of late. Personally, I'd get a hold of YT directly, get a new one, take off the other 15, and sell them.

There's a reason why SEVERAL builders tell you to just stick with stock rockers and a trunion upgrade.

miami993c297

iTrader: (6)

I will not be affirmative this stamp position is the "new one"...

- According to YT AUS, the after 2010 upgraded new and last model (for now) Ultralite's are stamped ON THE RIGHT DIDE

- The before 2010 model (the one's breaking more than usual...) are stamped IN THE CENTER

- The before 2007 model are stamped one are stamped ON THE LEFT SIDE.

Those one for the OP pics appear to be old model...
Christian

Darkman

iTrader: (2)

The key question, since the YTs have a known limitation.

vettenuts

iTrader: (4)

The other question is how narrow did you set the original wipe pattern of the rocker. This will also change the loading within the rocker. Now might be a good time to check that before replacing parts.

1slowbusa

iTrader: (8)

This is what I found online. I would call yella terra and try to get the entire set replaced.

What is the warranty on rockers?

STREET TERRA rockers are guaranteed against faulty workmanship and materials for a period of 12 months from date of purchase, subject to conditions below. TELLA TERRA rockers are also guaranteed against faulty workmanship or materials for a period of 12 months from date of purchase. We have such confidence in the quality of Yella Terra rockers, we offer a limited lifetime guarantee against breakage of the extruded aluminium arms, precision alloy steel trunnions or shafts and posilok nuts, while you own them.

This guarantee is subject to the following conditions. You must be the original purchaser and produce an acceptable original sellers invoice. These warranties do not extend to cover faulty installation or maintenance or to subsequent damage whatsoever. Perfectune engineering, the manufacturer, reserves the right to examine any goods under claim and shall be the sole judge of the validity of each and any claim and repair, replace goods at our sole discretion. All freight charges are the responsibility of the claimant.

1slowbusa

iTrader: (8)

I purchased my yella terra about a year ago and in the picture you can see on the second rocker from the left, the 1.7 is on the right side.

miami993c297

iTrader: (6)

- Wipe pattern?
- Lifter preload?
- Pushrod technical info?
- Lifter technical info?
- Camshaft type and cam-card?
- Valve weight?
- Valve spring technical info?
- Rev-limiter set-up?
.......

1slowbusa

iTrader: (8)

Good point, get all the information listed by miami and contact Yella Terra. I would try and if they replace them great, if not then look for another sollution.

Talk is cheap.

7beast

iTrader: (30)

hope they replace the one rocker man then sell them and go with oem rockers

flintwrench69

iTrader: (11)

This is what I believe.

Springs were new with rockers, Trickflow duals, not sure what the life expectancy is with the mild cam I run.

TSP 228 cam, 114 lsa
TFS 215s w/ TFS dual springs.
LS7 lifters, new when installed heads


Don't know what the open spring pressure is, I put lots of track passes as well, bounced off the limiter so I'm not too suprized it happened

I bought mine in June 2010, since it was a known problem then figured I was getting the revised ones but yours look a lil different so I must have the older ones.

Most of what your asking is fairly self explanatory as far as technical info:
TFS 215s
TSP 228 cam, 114 LSA
LS7 lifters, & new lifter trays
Trickflow 7.550 5/16 pushrods

6800 rpm rev limiter
IIRC, .050 lifter preload its been 3 years since I did the work.

sabastian458

iTrader: (5)

Limited life time warranty. Those are not the new ones. Search my history and see my thread on the rockers. Contact info for YT is there for a quick response.

Aggressive lobe ramps combines with high spring pressure cause the failure most of the time. Need to keep your spring pressure under 410ft/lbs.

flintwrench69

iTrader: (11)

400 lbs open spring pressure, according to info on trickflows site.
I'm gonna find out if they will replace the whole set with the revised ones.

Keep in mind when I said Another broken Yella Terra rocker arm, this is the first one I had break. It cant be from improper setup as much as I've driven the car with these.