Hi. This video shows - step by step - restoration of damaged rocker arms hard welding - grinding - polishing - coating . . . for more interesting videos click ,, HERE " / @paulxchannel
Good Job, as you would be aware, as long as the Camshaft is Case Hardened more than the Rocker Arms, it should be Ok, if the Rockers are Harder than the Cam then you have Problems!
@@pbysome Yeah, for the most part, but eventually parts wear regardless of lubrication, you're better off having a camshaft with a higher Rockwell rating than the Rockers or you'll wear the cam prematurely, you can replace the rockers or weld & grind them for less cost than a new cam - Cheers👍
@@purebloodheretic4682 in my experience rockers, or followers, are of a similar hardness, stellite is often used on followers and chilled steel on cams. Get the clearance correct and use good quality correct grade oil upkeep maintenance and there should be no issues.
NIce job, using relatively simple tools.. i love your grinding machine.. i would have used oilstones after grinding the rockers, first an India stone, and then an Arkansas.. a quick touch up with the polishing wheel afterwards.. and Bob's your Uncle.. the coating afterwards is for sure a good thing..
Paulo belo trabalho ficou show parabéns, cara nos ajude aí em mais informações na sua construção da ferramenta de retifica de sede valeu forte abraço aqui do Brasil
Always Nice Job. With all respect! You must heat with Torch Light the rocker arms after all the repair job but before the final buffing, till you see small tiny flames and metals goes out of the arms that time immediately put it on small can with engine oil you have for recycling. That called metal painting/strength. 3 times per arm & their gonna be as strong as it was and after all make final buffing! Its not necessary but it help for brand new Cams. Keep Up the Good Work as Always!!
these cams are cast, they have to be welded with a cast iron coated electrode. They should also be left to cool submerged in sand, or lime, so that cracks are not generated in the piece. it is possible that after a few hours of work they will break. In any case, they look great on you! engine sound is good. good luck!
Hmm hardfacing the rockers is interesting. I would have gone in with 954 aluminum bronze but I'll be interested to see if the cam holds up. You did get a good heat treat on it so they should both be at a comparable surface hardness. If you see spalling or excessive iron content on an oil analysis that wound indicate one or both parts is coming apart.
good work. maybe better than new, because that doesnt look like good quality.. just a liitle proposal: I would have applied heat for extracting the bolts.
Both cam and rockers look very nice! What alloys were used? I know the cam/lifter interface is a difficult lubrication situation, especially during the unfortunate moments of inadequate oiling that happen. I thought qualities other than just maximum hardness were important. I like these 1st Gen trx350's. High steering effort at low speeds! I think they might have a tight LSD in the front. I used to work on them at a dealer. Saw a cam failure, replaced a few CDI's. Too bad they used drum front brakes...not self adjusting, I think. Many were used hard and hardly maintained. Please comment on alloys used, galling resistance, etc. if you read this!
Did you make the tool that you used to easily remove the rocker arm pin? I'm look to purchase something similar, ER25 5 collet and a collet nut is all I have atm, where can I get the rest of the things? Ty
I have no machining experience. I wonder about the same issue as toastbrot. How do you know that you have the correct radius/height/dimensions on rocker arms that will provide the correct valve opening and duration? Is it all brought into spec with valve adjustment?
Does this get good life? I've always assumed you'd want your cam to be the hard part and the follower to be soft, since the rocker arm is easier/cheaper to replace than the cam. Or do you just make them both as hard as chinese algebra and everything lasts long enough as is?
Technical question: the original cam would have been drop-forged, machined and then case hardened to give it core strength and surface hardness. Will the new cam retain those characteristics being machined from billet? FYI I’m not a machinist but I am involved in a manufacturing. I also had a Honda cam/rocker fail in the same way on a similar age machine. Great work btw.
experience from a underbone racing mechanic: most reasonable part for that damage is lack of oil going to the cylinder head, oil starvation is the main cause of this, maybe from clogged oil filter or just negligence from the owner and also the valve clearance of the valve screw itself, no matter what kind of material used in camshaft as long it has lubrication it will last, we used local brand camshaft or just welded camshaft and grind it, it still serve it's purpose as long as it has lubrication
It would be nice to put a roller on the end of the rockers, being they are being reshaped anyway, put about 15mm roller on it, with about 9mm in bronze bush, about 1.5mm thick, leaving room for a tool steel roller, roughly 2mm thick, may need to reduce the roller a bit, surely 12mm od roller would fit, with 8mm in bush, leaving 1mm for roller and 1mm bushing, roller on both ends???
All good interesting stuff, but the radius of the cam follower alters the lift, duration, valve timing. Seems to me that you just got the radius by grind and guess. I played with follower radius a million years ago, in the days when you had to draw all the graphs by hand. Very time consuming. Sure computers have made it much easier... Oh, and I just scrapped a TRX350 with a good top end.... Seemed a waste, but the bike was just rust and shattered plastic.
