AarhusTr6 Posted December 28, 2020 Report Share Posted December 28, 2020 Hi guys I have my head away with Peter Burgess at the moment who is going to be doing a nice clean up on it. meanwhile I decided to give a cleanup of The Rocker and can see some of the rocker arms are quite sticky whilst others actually spin all the way around ie 360 degrees one of them was really quite stuck and I have been able to get it to move again but my question is should I strip this down because I'm not a great believer in taking things apart unecessarily and I'm concerned about putting it back together again. I think what confuses me is why do some rocker arms move just a bit and another ones I can rotate it fully thanks in anticipation Quote Link to post Share on other sites
DaveN Posted December 28, 2020 Report Share Posted December 28, 2020 You’ve gone as far a sending the head for rework. Personally I would strip the rocker shaft assembly too. Lay it down on a nice piece of board and pull it apart keeping all the parts in order of removal. Quote Link to post Share on other sites
jerrytr5 Posted December 28, 2020 Report Share Posted December 28, 2020 Take it apart and replace the shaft. The 'sticky' ones are probably where they have worn the shaft. It's almost worth considering the shaft as a consumable. If you get the reassembly wrong it will be obvious as the rockers won't touch the valve stem. Jerry Quote Link to post Share on other sites
Tom Fremont Posted December 28, 2020 Report Share Posted December 28, 2020 These will last indefinitely ( 100K+ miles ) bushed with bronze. Both my '250s have these which were done by Rocker Arms Unlimited in the 'States and my spare engine is getting them done by the engine builder. With this upgrade and hardened timing chain wheels these engines should be good for 150,000+ miles between rebuilds with regular oil changes and good control of A/F ratio. Tom Quote Link to post Share on other sites
AarhusTr6 Posted December 29, 2020 Author Report Share Posted December 29, 2020 Thanks for feedback I am not up to the budget of sending away, the cyl' head is costing enough! I dont understand though one thing, Jerry said re - assemble as it came or push rods dont fit? if I put a new shaft on what does it matter? Thanks Richard Quote Link to post Share on other sites
JohnC Posted December 29, 2020 Report Share Posted December 29, 2020 When I rebuilt my engine a while back the rocker shaft was very worn. Ridges very noticeable. I replaced it and shafts as well, but when comparing new & old rockers there wasn't much difference. As Jerry said, treat the rocker shaft as a consumable. They're not expensive. As far as assembly, I think Jerry just means that if you put the rockers in the wrong order they may not be over the relevant pushrod. They are angled in plan view. John Quote Link to post Share on other sites
jerrytr5 Posted December 29, 2020 Report Share Posted December 29, 2020 17 minutes ago, JohnC said: As far as assembly, I think Jerry just means that if you put the rockers in the wrong order they may not be over the relevant pushrod. They are angled in plan view. Yes, that is what I meant. Thanks. Jerry Quote Link to post Share on other sites
AarhusTr6 Posted December 29, 2020 Author Report Share Posted December 29, 2020 thanks so much! I'd click the thanks button if there was one! Quote Link to post Share on other sites
BlueTR3A-5EKT Posted December 29, 2020 Report Share Posted December 29, 2020 Regarding rocker shafts Original Triumph ones are supplied without end plugs, which must be fitted or the oil just dribbles out the shaft ends rather than oiling the rockers. Peter W Quote Link to post Share on other sites
AarhusTr6 Posted December 29, 2020 Author Report Share Posted December 29, 2020 Thanks, if I replace the shaft only, is this being silly or show I also replace the arms too? Peter, I think I understand you - - are these like grub screws on the end of the shaft? Richard Quote Link to post Share on other sites
BlueTR3A-5EKT Posted December 29, 2020 Report Share Posted December 29, 2020 (edited) 31 minutes ago, AarhusTr6 said: Thanks, if I replace the shaft only, is this being silly or show I also replace the arms too? Peter, I think I understand you - - are these like grub screws on the end of the shaft? Richard The plugs for the original shaft are very small bucket shaped core plugs Latterly, screwed plugs are fitted to repro rocker shafts which serve the same purpose to seal the shaft each end. Peter W Edited December 29, 2020 by BlueTR3A-5EKT Quote Link to post Share on other sites
ed_h Posted December 29, 2020 Report Share Posted December 29, 2020 Inspect the rockers and test the fit on the new shaft to decide if They need to be replaced. They wear in the bore and on the tip that bears on the valve stem. Ed Quote Link to post Share on other sites
Tim D. Posted December 29, 2020 Report Share Posted December 29, 2020 If you replace the shaft be sure to give the insides a good clean as they are often full of swarf. I also found that some of the drilling that feed oil to the rockers needed deburring. Without doing this the rockers jammed. In my opinion this should have been done by the producer. Tim Quote Link to post Share on other sites
astontr6 Posted December 30, 2020 Report Share Posted December 30, 2020 14 hours ago, Tim D. said: If you replace the shaft be sure to give the insides a good clean as they are often full of swarf. I also found that some of the drilling that feed oil to the rockers needed deburring. Without doing this the rockers jammed. In my opinion this should have been done by the producer. Tim +1'In my opinion this should have been done by the producer.' But it did not come from a quality supplier? That of course makes you think what else is wrong! Deburring and blowing out the swarf is normal engineering practice, at least it was in may day as an apprentice? Bruce, Quote Link to post Share on other sites
AarhusTr6 Posted December 30, 2020 Author Report Share Posted December 30, 2020 Hi all Sorry if this is too rookie, I guess I could go down the garage and check . . but is the rocker shaft hollow and with pin holes in it to allow free oil flow..?? Richard Quote Link to post Share on other sites
john.r.davies Posted December 30, 2020 Report Share Posted December 30, 2020 Yes, it is, Richard. The internal diameter of the inside bore, and the metered flow from the cam shaft rear bearing, means that flow through the shaft is very slow, especially towards the front, furthest from the supply. With age, that encourages deposits of gunge that can further inhibit flow. A rebuild that re-uses and old shaft should always include the use of a bottle brush up and down the bore! Quote Link to post Share on other sites
Tim D. Posted December 30, 2020 Report Share Posted December 30, 2020 3 hours ago, astontr6 said: +1'In my opinion this should have been done by the producer.' But it did not come from a quality supplier? That of course makes you think what else is wrong! Deburring and blowing out the swarf is normal engineering practice, at least it was in may day as an apprentice? Bruce, The shaft in question came from one of the big two suppliers of triumph parts. Quote Link to post Share on other sites
AarhusTr6 Posted December 30, 2020 Author Report Share Posted December 30, 2020 3 hours ago, john.r.davies said: Yes, it is, Richard. The internal diameter of the inside bore, and the metered flow from the cam shaft rear bearing, means that flow through the shaft is very slow, especially towards the front, furthest from the supply. With age, that encourages deposits of gunge that can further inhibit flow. A rebuild that re-uses and old shaft should always include the use of a bottle brush up and down the bore! Thanks for the education John! Quote Link to post Share on other sites
PodOne Posted December 30, 2020 Report Share Posted December 30, 2020 8 hours ago, john.r.davies said: Yes, it is, Richard. The internal diameter of the inside bore, and the metered flow from the cam shaft rear bearing, means that flow through the shaft is very slow, especially towards the front, furthest from the supply. With age, that encourages deposits of gunge that can further inhibit flow. A rebuild that re-uses and old shaft should always include the use of a bottle brush up and down the bore! Hi John Given this seems to be a long term problem of reduced oil to the front rockers is there anything that can be done to maintain the flow? Reason I ask is that I'm in the process of rebuilding my engine and have purchased a hardened shaft and bushed rockers from Chris Whittor so anything I can do while its in bits would seem sensible. I'm aware of the extra oil feed kit but it seems to receive mixed opinion as to its benefits is there a better way or is it just a case of regular oil changes? Cheers Andy Quote Link to post Share on other sites
john.r.davies Posted December 30, 2020 Report Share Posted December 30, 2020 (edited) Please don't mention the "extra oil feed kit" if that means the external oil line, because that triggers my Witchfinder General haunting, and .... YEaAgh, Brothers and Sisters!!! Verily it is said that the Eternalle Oile Linne is YE SPAWNE of YE BEELZEBUBBe!!!! Downe I sayy, downe on your knees and REPENT!!! Oh, dear, Vincent Price is back. Look, the OD diameter and slow flow isn't the issue. They just allow eventual gunge up, but that takes many years and neglect. Triumph carefully arranged a metered flow, and that is sufficient, unless you have needle roller rockers. John Edited December 30, 2020 by john.r.davies Quote Link to post Share on other sites
PodOne Posted December 30, 2020 Report Share Posted December 30, 2020 13 minutes ago, john.r.davies said: Please don't mention the "extra oil feed kit" if that means the external oil line, because that triggers my Witchfinder General haunting, and .... YEaAgh, Brothers and Sisters!!! Verily it is said that the Eternalle Oile Linne is YE SPAWNE of YE BEELZEBUBBe!!!! Downe I sayy, downe on your knees and REPENT!!! Oh, dear, Vincent Price is back. Look, the OD diameter and slow flow isn't the issue. They just allow eventual gunge up, but that takes many years and neglect. Triumph carefully arranged a metered flow, and that is sufficient, unless you have needle roller rockers. John Fair enough John ! I'll stick to regular oil changes before you come round and burn me at the stake for my herisy! Andy Quote Link to post Share on other sites
AarhusTr6 Posted January 2, 2021 Author Report Share Posted January 2, 2021 Hi all Well I was brave enough to dismantle the rocker today... So some of the rockers were very hard to get off, so needed quite a lot of spray. When I got it all apart i soaked the rockers in petrol and scrubbed them, then cleaned gently inside and on the sides with emery paper and a narrow wire brush. The are now overnighting in petrol and I will clean again and oil them - but overall they look okay but one had a sharp edge and I filed it down. The shaft is not bad, but some rough areas on it. I tried rubbing with emery paper also but the grooves on some are quite deep so I think I replace. Overall, it looked like it suffered dryness. I have 2 curiosity questions though: What material are the rockers and the rocker pillar/holder made from - is it aluminium? The rocker shaft, what do the grooves cut on it do, is it to help oil get around? Thanks for help so far, Quote Link to post Share on other sites
Waldi Posted January 2, 2021 Report Share Posted January 2, 2021 Hi Richard, the pedestals are an aluminium alloy. The shaft is a rather soft steel. You can buy tuftrided shafts from Moss and others, I have one, but not installed it yet. The flat area’s are to aid lubrication. Make sure the bore is clean too because debris may plug the oil holes easily and check for alignment of the bore in head, pedestal and rocker shaft. The rockers are made from cast iron I think. Avoid new repro ones, think Roger had a failure (fracture) a couple of years ago, do not know what caused it. The tips are insert-hardened, check for wear. I dressed a couple, but if you have to remove too much material replace them, because the hardened layer is not thick. Cheers, Waldi Quote Link to post Share on other sites
AarhusTr6 Posted January 2, 2021 Author Report Share Posted January 2, 2021 1 hour ago, Waldi said: Hi Richard, the pedestals are an aluminium alloy. The shaft is a rather soft steel. You can buy tuftrided shafts from Moss and others, I have one, but not installed it yet. The flat area’s are to aid lubrication. Make sure the bore is clean too because debris may plug the oil holes easily and check for alignment of the bore in head, pedestal and rocker shaft. The rockers are made from cast iron I think. Avoid new repro ones, think Roger had a failure (fracture) a couple of years ago, do not know what caused it. The tips are insert-hardened, check for wear. I dressed a couple, but if you have to remove too much material replace them, because the hardened layer is not thick. Cheers, Waldi Dank Je Waldi I hope to keep the rockers, and buy a new shaft but will give the shaft a good scrub and clean. Richard Quote Link to post Share on other sites
ed_h Posted January 2, 2021 Report Share Posted January 2, 2021 I think Waldi is right about the rockers being cast iron--You get that characteristic powdery swarf when you drill them. I didn't notice evidence of an insert on the tip, though . The tips are hard, maybe case hardened. Removing 8 to 10 thousandths from the face didnt seem to expose soft material, just judging from a crude file test. Ed Quote Link to post Share on other sites
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