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Rocker Arm question

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Most of the B engines I've worked on needing rocker bushes/shafts replaced were either neglected or high mileage ones. If PM is neglected (e.g. L.O.F.) the wear rate is seemingly exponential. I've seen 100K Mi. engines as neat as a pin and 40K Mi. ones paggered to ruin. The tips are subject to the same neglect as well. Tough, useable if kept lubed, scored and chewed if L.O.F. changes are neglected.

That said, I'll also tout "modern" lubricants: Castrol 20~50w and the Synth's and blends do a MUCH better job than the old single 30w and non-detergent oils the original spec's called for. Less friction is always a "better thing" but you still have to ~change~ it on a regular basis /ubbthreads/images/graemlins/wink.gif
 
LOF.... Lube, Oil, and Filters?
 
oh yeah... I forgot to ask... when you replace the rocker assy. Do you also need to change out the push rods or can those generally be reused? What about the tappets/lifters? Valve springs? Last check my compression was good. So, I assume my valves are sealing properly, and in theory I shouldn't have to replace the valves and springs, right?

I'm almost afraid of trying to get at the tappets... I almost feel that if I have to go digging after those things I may as well change the cam too.... heh
 
LOF=Lube, oil & filter, yes.

Various schools of thought re: pushrods/tappets. theoretically the rods are turning constantly and "bed" into the tappets & rockers and shouldn't be "juggled" but kept each with its' original set. Unless they appear really worn or bent though, I'd chance replacing just the rockers. Check the tappets too. Especially for cracking at the hardened cam interface surface. They can be "retrieved" using a wood dowel with a piece of paper towel wrapped tightly around one end and jammed into them. Better way is with a good wand magnet. Either way the challenge is getting them BACK in their bores. Patience here is key. Otherwise you'll be pulling the intake and exhaust manifolds to get the access covers off. I've done it many times with everything in situ, but it IS easier with the covers off. Not sure how accessable yours are due to the exhaust manifold but on earlier cars the covers can be removed with the manifold in place as well. Challenging but "do-able."

Careful with that "may as well do the cam too" thingie: slippery slope. Next thing will be "Aww, I may as well just pull the engine and go thru the whole thing." IY$WIM. /ubbthreads/images/graemlins/wink.gif
 
As Dr.Entropy said, you should have no problem re-using the other components when you replace the rockers. However, if and when you replace the cam, fit new lifters at that time as they need to wear together. Old lifters on a new cam can result in premature wear. The pushrods can generally be re-used with any combination of new/used parts as long as they aren't bent.

LOF... In the first sentence I thought you meant "laughing on floor" (laughing at PM). By the second use of the abbreviation I knew you meant Lube Oil Filter!
 
Yeah, I've certianly thought about pulling the engine on more than one occassion. But currect circumstances prevent me from going that far. However, if I ever did pull the engine I'd put a lot of serious thought into swapping in an OD unit or doing one of those 5-speed conversions... because I'm *always* looking for 5th gear while I'm driving... heh /ubbthreads/images/graemlins/laugh.gif
 
The "Searching for 5th Gear Syndrome" is well understood: I drive an Alfa (5-cog) daily, and on occasion will actually shift a four speed out of fourth before I realize I'm an ~idiot~. Habit as embarrassing as plugging that W I D E power brake pedal in an auto tranny car, looking for the clutch in reaction to a surprise situation... once had my Old Fella danglin' forward from the seatbelt, wheels locked, doin' this in his Lincoln 'cause something occurred in front of us and I just reacted out of habit. After the adrenalin had dissipated we had a good laugh over it (at my expense of course).
 
I can relate to that! I got into an automatic trannied Volvo last summer, with a floor shift, and just about banged my face off the windshield when I hit the "clutch" to upshift to second. (Quick look around to see if anyone saw me.)
Now my daily driver is a four speed with an electric OD, and I find myself looking for sixth!
I guess some people are never satisfied, eh?
Jeff
 
i'm guilty of both of the above situations... Even to the point that I've put the B down into third gear before I realize there's no 5th, thinking that's what 3rd was. Fortunately I usually realize this before I let the cutch back out.
 
ya know, the real kicker for me is I haven't driven a 5-speed stick in over 3 years, and I'm still searching for it every now and then...
 
The only 5-speed in our fleet is a Wrangler, and with 33 inch tires on it, 5th gear is useless, so I don't even think of 5th gear anymore!

Bruce
 
You could call shifting to 5th "upshifting for down-slowing."

You *are* close to "PA Deutsche" country, no? /ubbthreads/images/graemlins/lol.gif
 
ok, I just acquired a used rocker assembly. At $24, I couldn't really pass it up considering the issues with the one in my car. Overall, the new to me (hereby known as NTM) assy is in much better condition. However, I have noticed two things that might be of concern.

1) the #3 intake valve has visible fore-aft twist play. This is the only valve on the NTM assy that has this amount of play. Best estimate for how much play is approx. 1/32nd to 1/16th of an inch. Much much less than the worst ones on my current assy.

2) The face of the #4 exhaust rocker appears to have been ground some how by some thing at some point. The face of this rocker is not smooth like the others. It has a definite grain that goes across the face and hits a bit of the arm, like it might have been put to a grinding wheel.

Other than those two issues, the assy. seems to be in good working order. The rockers rock smoothly, and the locator springs ... spring. Now, my question here is can I swap two "good" valves from the old assy. and put them on the NTM assy. to make an overall better rocker assy?

The #3 intake rocker seems to be ok for the most part, and I'm not entirely sure I should replace it. However, the #4 exhaust rocker definitely bothers me. I don't want this course face grinding away at what's left of my valve stems.

Thoughts, and opinions anyone?

thanks

***EDIT note: Apparently I'm having spelling issues tonight
 
Sounds to me as if the #4 arm has been MacGyver'd. The "pads" (the part of the arms contacting the valve stem) are surface hardened. If that'n has been ground as crudely as you describe, condemn that rocker to the "wall of Shame" and replace it. Juggling your "best" old one(s) to the NTM shaft will work. Previous posts by all concerned describe "the best of all possible worlds" where new bits and machining are concerned, but practically (a "driver", a non-racing engine) your fix will work fine. You'll think it a new engine after this work. /ubbthreads/images/graemlins/wink.gif

Word in yer ear: go through the NTM shaft ass'y with "hospital" cleanliness, i.e. disassemble it, clean/wash all parts WELL in mineral spirits, check all the shaft oil passages and the ones in the rockers as well. Same with the arm(s) you transfer from the old shaft. Blowing compressed air thru the oil passages in the arms helps. If you've no access to a compressor try camera shop "canned air." Works well in a pinch.

IIRC there are differences between 18G and 18V shafts (oil port/pedestal variants), but for the life of me I can't recall exactly what they are... check the shafts closely, side by each when they are both apart... NTM shaft may not be "as billed" IYSWIM.

That's the list of things I can think of checking/doing, goin' thru the deed in my li'l pea brane
HTH. /ubbthreads/images/graemlins/cheers.gif

Edit: Already thought of more: Assembly lube as you reassemble and reinstall arms/springs/shaft. A 50/50 "slurry" mix of your normal engine oil and "Motor honey," "STP" or equivalent works great.
 
I assume I can pick up rocker shaft assembly lube at any local parts store, no? I've never had to get any in the past, so that's why I ask. Does it have to be mineral spirits? Or can I use something else like "Simple Green" degreaser? I need to de-crud the used king pin+axel stub assys before I put it on the car. If I can clean up the rocker assy with the same stuff (not necesarilly in the same container at the same time) that'll be great.

I'm hoping to do all this work this weekend. I've had parts stacking up in my room for the past couple weeks, and I finally got most of the new parts I've been waiting on from Moss (i.e. trunion and fulcrum pin sets). I'm gonna stop off at the local OSH and grab up a BFH ( don't already have one /ubbthreads/images/graemlins/rolleyes.gif ) and some cleaning solutions. Besides axle greese for the axle stubs, penetrating oil, and the lube for the rocker shaft, is there anything else I should be picking up for this project (swivel axel swap and rocker assy swap)?
 
You could just use lithium (white) grease for "assembly lube". The mineral spirits is a very good cleaner/degreaser and Home Depot carries it by the gallon. Get a few 1" "bargain" natural bristle paintbrushes there as well... disposable parts washer brushes! If they need to be "stiffer" just cut 'em back a bit with scissors. DO NOT clean the rocker stuff inna same "pot" as the suspension bits! /ubbthreads/images/graemlins/wink.gif

Keep us up on your progress.
 
lithium grease for the rocker assy, or for the swivel axel assy, or both?
 
No harm using it on both as assembly lube. Be sure to grease the pins with a grease gun after assembly (three points on each ass'y) and you should be good to go. Using a light film of lith grease on the the rocker assembly is fine. Oil will get there on startup and the white grease will go into solution. The only situaton to avoid using white grease as assembly lube would be if you intended to let the assembly sit for some time before installing/using it. The 'carrier' in the grease evaporates over time and the grease becomes harder, losing some of its benefit as a "pre-lube."
 
If you bought the bearing kit from Moss, it comes with a little packet of axle grease in it...and plenty of it.

Bruce /ubbthreads/images/graemlins/cheers.gif
 
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