Rocker Geometry Woes

[EuroDat]

Sounds like your muffler had some coolant in it and took some time to boil out. Hope thats all it is. Good to hear its running again. Ready and Looking forward to the summer

Chas

[71Nissan240Z]

Glad it worked out for you.

[Zed Head]

i decided to drive around the block just for kicks, 

I like this part.  Doom looking in you in the face --- screw it, I'm getting one last ride in.

[rossiz]

@Zed - yes, i was not going to be denied...

made it to the office this morning w/no drama (16 miles) including some wonderful stop-n-go and some freeway cruising. 

i am cautiously optimistic.

[S30Driver]

Excellent news...

Probably condensation from sitting for a month was a contributing factor to the cloud effect at warm up.

[rossiz]

well.... 

 

i was going to post up about how well the car is running with the 2nd head.

i was going to post up about how i did a valve lash adjustment at 500 miles and now the exhaust note has more tooth, and it pulls great right up to 6k and how it has a lot more punch.

 

but just thinking those thoughts jinxed me...

 

driving home from work this afternoon on the freeway, cruising along and a horrible noise came from up front and the car started missing, stuttering and i limped off at the next exit, stalled at the light and barely got it to a very conveniently located shell station across the intersection. thought i'd blown a head gasket - but no change in engine temp, no puff of smoke out the back, no change in the coolant reservoir... pulled the plugs - all looked ok. it would start with much coaxing and only barely ran above 2K rpms. definitely not able to limp it home. called AAA and received the friendly reminder that i had used up 3 of my 4 tow service calls in my service plan year (yes, i know, i know) and they would be out in an hour or so.

 

while i waited, i decided to peek inside the valve cover. pulled out my handy tool bag from the handy storage compartments behind the seats and when i lifted the cover off i was literally shocked at what i saw. the #2 intake rocker had fallen off!!! yes, my L6 is literally "off it's rocker". the middle of the head looked like my kitchen junk drawer - springs, keepers, lash pad - all strewn about willy-nilly in there. 

 

i poked around with a magnet and much to my joy and surprise, i was able to retrieve every single bit - even the two valve stem collets!! i can't believe nothing fell down the "hole of doom" into the front cover. one of the collets gave me a scare until i noticed it hiding inside the socket recess of a head bolt up on the cam tower!. i even retrieved the broken spring that popped off the top of the valve guide seal. the valve was down about halfway, so i don't know if it got damaged - i'll peek in with my endoscope camera and see if there's a mark on the piston crown. 

 

so i collected all the bits in a plastic bag (felt like a crime scene investigator) and got her towed home. will pick up a new seal tomorrow and try to put humpty back together again.

 

to be fair, this is NOT the fault of datsun parts LLC - they were more than fair in sending the second head, even though it was long past the warranty period, they also sent a new head gasket and manifold gasket at no charge. the new head is (was?) definitely an improvement. the fault lies squarely with me on this one - i must not have properly torqued the rocker adjustor, as it was loose and just backed its way down into the head until the rocker just fell off. 

 

from the outside it doesn't look like the parts got damaged or damaged anything else - they miraculously just sat where they fell.

 

the saga will continue...

 

The mess i found:

   

 

The ride of shame (again) - but she looks kinda cute w/those mickey mouse ears!

[Zed Head]

Odd.  It should have kept running on 5 cylinders.  Better check your cam timing,  Maybe the sprocket's loose and you sheared the sprocket dowel.  Might explain a piston doinking a valve, and the fact that it wouldn't keep running on 5.  I hope DPLLC didn't send you cam with a bad dowel (I just can't let the guy off the hook yet).

[Captain Obvious]

Man! You've got the worst luck... It's like you just can't catch a break!

 

I'm a little confused about what it was that caused this failure. You said the rocker adjuster was loose and walked it's way back down into the head until the rocker became so loose that the rocker wasn't retained enough anymore and fell out of position. That can explain how your car got off it's rocker, but what's your theory as to how the valve keeper split collets came out? I'm thinking that those split collet retainers should never come out as long as the valve stem is help in tension.

 

Maybe the rocker flopping around in there hit the side of the washer on top and released the tension on the keepers?
 

[madkaw]

Hate to see this kind of carnage-sorry about your luck. 

[Mark Maras]

OMG! Not again. Thumbs up on finding all the parts, Curious if the inside of the valve cover shows any scars. Can,t imagine the collets coming loose unless something compressed the spring. Considering the fact that you "know" this car in the Biblical manner by now & you mentioned that it is a she, could her name be Lillith? Keep treating her with love, she will give up her tantrums & be your friend.

Mark

[cbuczesk]

I had the same thing happen on my race car last year. I'm sure that I tightened that nut and double checked it but somehow it came loose and the "bolt" backed down until the rocker and lash pad fell off. But that's as far as it went. The keepers and everything else stayed in place. I also wonder what made your keeper pop out. Maybe as the rocker was exiting it pushed the retainer down but the valve stayed in place allowing the keepers to pop out?

 

Chuck

[siteunseen]

Awe man, bummer!

 

What's that needle looking thing beside the keeper in picture #3? 

 

I had to use a sharp pointed pick to get the spring keepers to even separate from one another with the springs fully compressed.