Took the heads off....found gremlin poop...

[Hemidoug]

Pulled the heads to get some work done and look what the gremlins left....1 cracked piston and 3 bent intake valves. Looks like the motor is coming out (again) and it's getting a rectal exam. At least I found it before any further damage. We haven't figured out the why just yet but the best guess it valve train geometry. It might be a roller rocker going over center at max lift or a pushrod hanging up. I had some scrapes on a couple of pushrods....hope to get it back next week. I know what I'll be doing on Father's Day....



   

[chargerrt]

I'm sorry you're having engine problems...that sucks.  The thread title made me laugh pretty good though.  At least you got that going for ya

[Rolling_Thunder]

ouchy

[1969chargerrtse]

  That ain't good.  You are amazing though, you must know that motor inside and out.  Maybe you can pull the motor while you're sleeping?  Save time.  As you said, thank god you found it early.  Hang in there man.

[firefighter3931]

Ah Crap Doug....sorry to see this 

Good thing that you caught it early ! 

Probable causes :

(1) sticking valves (tight valve guides)
(2) valve float (weak or incorrect valvesprings)
(3) Piston to valve clearance too tight


Keep the faith man ! 



Ron

[BrianShaughnessy]

That sucks but glad you found the problem before it went catastrophic. 

[Hemidoug]

Thanks Ron...I will. You forgot to add one thing to your list. Bad valve train geometry.... The general consensus is the roller rockers were going over center on the valve stem at high RPM locking the valve at max lift. The piston would hit the valve and force it back the other way. We will be checking that as well.....That valve was wide open when it was hit.....Now I know why I was only turning 12.6.....

[tan top]

  oh crikey Doug  sorry to see this  .. good job you wipped the heads off  when you did   

[Charger_Fan]

Were you starting to lose compression from the bent valves, is that why you yanked the heads? Or did you hear noises?

[hemi68charger]

Dang Doug !!!  Sorry for the bad news.................  My body drama is your engine drama...............  You'll get her smooth out soon I'm sure........

Troy

[Hemidoug]

Were you starting to lose compression from the bent valves, is that why you yanked the heads? Or did you hear noises?

Na, just a hunch. It didn't feel right at Englishtown and I knew the motor had some bugs in the valve train/heads. Soooooo, I started digging.......

[69*F5*SE]

That hunch saved you a bunch I would assume.   

[Just 6T9 CHGR]

Good to hear you caught it early Doug!  Down but not out

[RD]

hey doug, you pulling the lower end too?  I have always wondered how such issues as yours would affect the bearings on the piston where obstruction has taken place... please keep feeding photos with the teardown.

Jamey

[Hemidoug]

Well, I just dropped the short block off at the machinist....it looks like just one intake and one exhaust valve were bent...the latest theory is valve float on a shift. I don't know what the fix is just yet, we're looking at a couple of options. In the mean time the motor is going to get a full going over to include cam timing, true compression calculation, clayed cylinders, heads cc'd, 5 angle valve job, new rings, head porting and flowing, and depending on compression ratio some head shaving....I want to get back to 10.25 to 1 on the c/r. Also investing in a GOOD set of pushrods as well as getting the valve geometry in shape.

[41husk]

Good luck man! just got the 440 back in the wanna bee tonight.  Sure hate not having it drivable!

[The70RT]

I guess the good thing is you didn't gernade it. I bet things are getting to be a bit expensive. Hopefully the next build will be better than ever 

[resq302]

Doug,  did this happen at E-town when you were making your time runs?  At least you caught it before the Pinks run.  Would have been bad to have the engine go boom possibly on TV.