1 (edited by gunn 2017-03-03 11:11 AM)

Topic: 302 SBF Q: should I be worry about this side-to-side rocker arm play?

All:
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


Background
- 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.

Observations
- 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.

Thanks,
-g

Quick video. You can hear the slopiness and a move it side to side
https://youtu.be/KISap106Guo

Myopic Motorsport's #888 Bosozoku Texino Thunderbird (1995 tbird w/ 93 V8 swap + shopping cart rear wing)

2 (edited by gunn 2017-03-03 11:59 AM)

Re: 302 SBF Q: should I be worry about this side-to-side rocker arm play?

I called a machine shop friend for advice and he suspects that the issue is because that specific lifter has probably just bled down. It's been sitting for a few weeks now since it was last run. When the engine was last stopped, that valve was open/shut/whatever and the lifter was drained.
- If I swap the lifter with another one and the sloppiness follows that lifter, it's probably the that it was drained.
- If I see wear on the underside of the rocker (on the pivot) and the issue moves to a different valve if I swap rockers, it'll be the rocker.

This also jives with similar feedback given in this thread.
http://vb.foureyedpride.com/showthread. … rocker-arm

Myopic Motorsport's #888 Bosozoku Texino Thunderbird (1995 tbird w/ 93 V8 swap + shopping cart rear wing)

Re: 302 SBF Q: should I be worry about this side-to-side rocker arm play?

Wait, engines can be taken apart?

Mistake By The Lake Racing (MBTL) https://www.facebook.com/groups/MBTLracing/
88 Thunderbird "What's the word? Thunderbird!", "What's the Price? Thirty Twice!"
A&D: 2014 Sebrings at Sebring (NSF), 2014 NJMP2 Jurassic Park (SpeedyCop), 2012 Summit Point J30 (PiNuts)

Re: 302 SBF Q: should I be worry about this side-to-side rocker arm play?

I have to agree that it's a lifter issue and not a rocker issue. In fact I don't think anything is really wrong. The lifter bleed down and now has some play. Start the engine up and then recheck it, I think you'll find that there is less play afterwards.

5 (edited by billybobster 2017-03-03 02:15 PM)

Re: 302 SBF Q: should I be worry about this side-to-side rocker arm play?

Guildenstern wrote:

Wait, engines can be taken apart?

Why yes. As I understand it, in the context of Lemons, engines are taken apart involuntarily.

http://www.roadkill.com/wp-content/uploads/2016/02/Fordsche-Engine-Block-1280x853.jpg

There may be voluntary and reversible techniques for taking an engine apart, but I have no specific recollection of these.

10X Loser - Delinquent Racing - '86 TRUMPACO Merkur - '17 Sears Pointless, '16 Pointless, Vodden, Arse-Sweat, Button Turrible, Arse-Freeze - 2015 Vodden, Arse Freeze. '96 Ford Taurus SHO Skunk - '15 Pointless. Button Turrible.

Re: 302 SBF Q: should I be worry about this side-to-side rocker arm play?

Makes checking the oil easier!

Re: 302 SBF Q: should I be worry about this side-to-side rocker arm play?

Tonight I learned that you cannot swap hydraulic lifters in a 302 without pulling off the head. Since that's not going to happen, I swapped rocker arms to see what would happen.

The side to side sloppiness followed the rocker arm+pivot so that's the obvious culpit. Upon closer inspection, you can see where the pivot sits in the rocker arm pocket is shiny like worn metal. It probably wouldn't matter but these 302 parts stupid cheap (it seems like 302 parts could be sold at 7-11 -- $8.50 shipped from rockauto) so I might as well replace it.

-g

Myopic Motorsport's #888 Bosozoku Texino Thunderbird (1995 tbird w/ 93 V8 swap + shopping cart rear wing)

Re: 302 SBF Q: should I be worry about this side-to-side rocker arm play?

gunn wrote:

Tonight I learned that you cannot swap hydraulic lifters in a 302 without pulling off the head.

Who told you that?

http://forums.corral.net/forums/11312752-post8.html

Mistake By The Lake Racing (MBTL) https://www.facebook.com/groups/MBTLracing/
88 Thunderbird "What's the word? Thunderbird!", "What's the Price? Thirty Twice!"
A&D: 2014 Sebrings at Sebring (NSF), 2014 NJMP2 Jurassic Park (SpeedyCop), 2012 Summit Point J30 (PiNuts)

Re: 302 SBF Q: should I be worry about this side-to-side rocker arm play?

Guildenstern wrote:
gunn wrote:

Tonight I learned that you cannot swap hydraulic lifters in a 302 without pulling off the head.

Who told you that?

http://forums.corral.net/forums/11312752-post8.html

Have you tried it yourself?

I tried pulling the suspect tappet out but it won't come straight out  because there's not enough room before you hit the bottom of the head. I got to the point where I would be yanking it them at an angle where the roller bearing would be pressed up against the upper lip of the tappet hole. Instead of risking scoring up that roller bearing, i decided to drop it back into it's hole and tried swapping rocker arms instead.

-g

Myopic Motorsport's #888 Bosozoku Texino Thunderbird (1995 tbird w/ 93 V8 swap + shopping cart rear wing)

Re: 302 SBF Q: should I be worry about this side-to-side rocker arm play?

Flat tappet lifters can come out with the head on, but if it was a roller lifter block the bores are taller- head off.