Topic: 302 SBF Q: should I be worry about this side-to-side rocker arm play?
I'm checking my tbird's egnine before my next race at the end of this month and found that when torqued down to spec (25 lb-ft), one of my rocker arms -- specifically the Cyl #4 exhaust rocker arm, seems to be exhibiting some side to side play that none of the other rocker arms exhibit
- Rocker arms are original stock ones w/ 185K mi on them plus a few Lemons races (1 full race, two which ended up as disasters).
- Pushrods are Sealed Power and new since my last rebuild (19 laps + 1 full race old). All were cleaned, oiled, and inspected for wear at the end tips (none) as well as being straight (rolling on flat surface).
- Hydraulic roller Valve Lifters are ford stock and all new since my last rebuild (1 race old); replaced because several had collapsed when my first engine significantly overheated.
- I did notice the two bolts in the valley that hold the plate that holds the lifter retainers were loose but I tightened those back up.
- NONE of the other rocker arms exhibit this side to side sloppiness on either side of the engine
- FWIW, there doesn't seem to be any play up/down (around the axis of rotation the rocker arm pivots around). I seem to recall that when the lifters collapsed they become sloppy along the axis of rocker arm rotation (which would make sense if the lifter wasn't lifting) vs side to side.
- Finally, I tried rotating the engine by rotating the crank and the behavior/sloppiness doesn't change (still with that rocker arm).
Q: Is this something to worry about considering the level of abuse the engine is going to go through in the next race?
What causes this?
- Is the lifter starting to go?
- Is the rocker arm out of spec/worn?
If so, what should I replace? Just that rocker arm assembly (with pivot), just the pivot, the lifter, or some combination of the above for both the intake/exhaust for that cyl?
I'd rather solve this issue now when I still have time to mail order parts vs right before the race (or evern worse -- during the race).
Any advice you can offer will be appreciated. Tonight I plan to swap the lifter/rocker/pushrod on that side to see if I can better narrow down what item is giving this odd behavior but given that some of you folks are actually mess with cars for a living and therefore have a ton more experience than me, you might have seen this before.
Quick video. You can hear the slopiness and a move it side to side