I'm getting my rocker assemblies cleaned-up for installation on the head. I have new tappets, and am putting them in. Question: Should I install lock washers between the rocker arm and the adjusting nut that threads onto the tappet? None were there when I disassembled them, though they were so tight I thought I might break on of the rocker arms. The arms are also threaded where the tappets run through them. Just thought it may be a good idea for some lock washers so they won't "self adjust". For those unfamiliar with my story, these had been sitting untouched (off the engine) for the last 35 years. Thanks for any help. Dave
Use just the nuts.
The bolts you show in the picture look soft, if they are they will give up fast.
Thanks for the response. The bolts used for the tappets were made back in 1980. The heads were round smooth, so I can't tell what grade they are, but the shop that did them had a good reputation back then for quality work. They were made to replace the old ones that had work thin due to lack of lubrication (the head never had a a rocker cover on it, so the arms and other moving parts didn't get much oil).
Any recommendations on replacements?
Boy, I don't Dave.
I would try Dan McEachern.
Thanks, I'll check with Dan. I may also check with Mark Chaffin, as he's now producing repro heads.
The rockers are threaded so the nut is a jam nut, or sometimes called double nut. It's better than a lockwasher. The only time it won't hold is when you have torque pulling the nut and jam nut apart. The only torque on rockers is when they are offset from the valve.
I agree with Herm. The bolts don't inspire confidence. I would take one and try a file on the edge. If a file "cuts" it easy it is probably too soft to last very long.
If you have a heat treating shop near by, you could talk to them. I would bet in Dayton Ohio there will be somebody in your city that can help you. Maybe they could be hardened up (and maybe they have been), but I am skeptical.
I figure he probably wants about 50 Rc or a little more for hardness. What do you think?
hard bolts is a good thing, but i see that those bolts have a shoulder machined on for a washer surface, which tells me they are high quality bolts like they made in the old days, not from china.les is correct however, strike it with a file, if it cuts its soft, if it slides across like its kriptonite you are in like super model t man
I figure he probably wants about 50 Rc or a little more for hardness. What do you think?"END QUOTE"
I don't know Les, I don't have a mental file on that anywhere, as it is over my head.
In the past when I needed something heat treated, or hardened, I made the part out of the steel that they told me, and sent the new parts and the old piece to the place that did it, and they tested it and treated the new pieces to the same hardness and sent them back.
Well, the bolts are not hardened. I was able to file them easily. Now I'm looking for a place locally that can harden them. Thanks for the info, all.
Dave, I used to be in maintenance at a local lead recycling plant. We had Lawson Products as a supplier for bolts and fasteners. They had bolts that they called Tru Torque, they were harder than Grade Eight. Might be worth checking out. Just a thought. Dave
Before spending on new bolts, I would try these, and only change them after they have worn. They might wear some until they make a proper angle to the valve stem.
A rocker broke in half on the Fronty several years ago, and I had it welded back together. That should have killed any tempering, yet that one has not worn any more than the others.
Tempering and hardening are two different things. The Roof rockers I have are HARD and seem to be right through. They have never worn at the tip or in the bore(the original shafts were quite worn). Obviously they were machinable at one stage as they were threaded and bored but now they are really really hard. it is a combination of metal composition and heat treatment
Thanks, all for chiming in. If I can get them hardened locally (I'm looking into what can be done with them at a few places here), I will. I have two sets of these bolts that fit, so I'm sure I'll be set for awhile either way.