Marcel Posted March 21, 2019 Report Share Posted March 21, 2019 . In February, in that lovely week I decided to take my 6 out for a drive, I was just thinking how well the car was driving when my lovely symphony of 6 cylinders changed into a possessed erratic kettle drum, nearly all power was lost and I pulled over. After getting the car home I removed the head cover and found one of the inlet valve was seized open, bent push rods and a damaged rocker. Only reworking the head last year I didn’t really expect to be removing my head this early. I had total oil starvation in the head, an expensive failure. I hadn’t looked at the rockers or shaft as these had been replaced before I brought the car less than 5000 miles ago, after disassembling the shaft I was horrified at the total lack of quality control of the components, these were updrated rockers. Have the look at the photos and tell me what you think, the supplier tells me this is completely normal and they have 40 other on the shelf to sell on. The top rocker shaft is my original shaft and lower one is my new quality shaft now supplied by Mark at Jigsaw racing, what a difference. Look at the oil channels in the rockers Ive now replaced all my valves, a rocker, replaced the damaged guide as I had replaced them all last year, light skim of the head while it’s off and fitted an external oil feed now. Hope to get the car running again next week. Quote Link to post Share on other sites
astontr6 Posted March 22, 2019 Report Share Posted March 22, 2019 I hope that you have filled in Roger's Q R form for sub standard work? Who was the original supplier? In my view people on the forum should be told so they do not fall into the same trap and expense. Bruce. Quote Link to post Share on other sites
Mike C Posted March 22, 2019 Report Share Posted March 22, 2019 (edited) AS you alluded to, the lube oil path is not complete in the top shaft. And these are still for sale? Edited March 22, 2019 by Mike C Quote Link to post Share on other sites
Marcel Posted March 22, 2019 Author Report Share Posted March 22, 2019 I’m trying to sort out the problem to the supplier, the technical department say this normal and customer services I’m still awaiting a reply after over a week. These parts should not be on the market. To me this is wrong the bushes have been pushed in and when drilled through from the outside have completely missed the oil channels. Every one is within a 1/4” but all different showing me they tried but failed. Quote Link to post Share on other sites
JochemsTR Posted March 22, 2019 Report Share Posted March 22, 2019 Marcel, who made your cylinderhead? Looks absolutely beautiful. Jochem Quote Link to post Share on other sites
astontr6 Posted March 22, 2019 Report Share Posted March 22, 2019 41 minutes ago, Marcel said: I’m trying to sort out the problem to the supplier, the technical department say this normal and customer services I’m still awaiting a reply after over a week. These parts should not be on the market. To me this is wrong the bushes have been pushed in and when drilled through from the outside have completely missed the oil channels. Every one is within a 1/4” but all different showing me they tried but failed. Quote: 'These parts should not be on the market.' I have a suspicion that this quality has been on the market for years like dodgy lay shafts which had been on the market for over 25 years! This is why Roger's form s/b filled in ASAP to cure the problem. Unfortunately, our TR suppliers often bury their heads in the sand and come out with their famous words . 'nobody else has complained' Keep on it Marcel! Bruce. Quote Link to post Share on other sites
RogerH Posted March 22, 2019 Report Share Posted March 22, 2019 Hi Marcel, I'm trying to get my head around what is going on. I'm not too knowledgeable on the TR6 engine but I assume it is similar to the TR4. The oil to the rockers comes from the back end of the cam shaft in pulses. Up the rocker shaft pedestal, along the rocker shaft and into the rockers. The shaft has a flat on it at the oil hole. When the hole in the rocker aligns with the flat on the shaft you get a squirt out of the rocker hole. This flat on the shaft will also feed oil into the rocker bush oil channel and act as a tiny reservoir. The hole in the rocker does not need to align precisely with the oil channel in the bush as the flat on the shaft will transfer the oil. On the 4A it is a split bush (two of them) so the oil channel is all around the centre of the arm. Your pics show that the shaft bush and arm should work. The bush surface looks tatty rather than smooth due to decent lubricated contact. Have you looked to see if there is a blockage between the back end of the cam and the rocker shaft hole at the arm. before putting the head back on spin the engine over to see if oil comes out of the hole below the shaft pedestal. If yes then fit the pedestal and shaft and repeat t see if oil comes out of the shaft at the dodgy rocker arm position. It is difficult to make any diagnosis from a few pics but I would stay clear of the external feed.. Roger Quote Link to post Share on other sites
astontr6 Posted March 22, 2019 Report Share Posted March 22, 2019 Roger, I would expect the oil hole to break into the oil groove on the rocker as the rocker shaft is a well known failure point on a TR6. I have had 3 so far in 45 years! The heat treatment of the rocker shaft is also critical and I suspect that the repro ones are soft? Moss do offer a specially heat treated version! Bruce. Quote Link to post Share on other sites
RogerH Posted March 22, 2019 Report Share Posted March 22, 2019 Hi Bruce, from an engineering point of view I would agree that the hole should align with the oil groove but does mass production allow that. The flat on the shaft should allow for oil transfer. Does the hole align on anybodies rocker arms? Having said that I have not seen a TR6 rocker shaft so may be taking utter hollihocks. Roger Quote Link to post Share on other sites
Marcel Posted March 22, 2019 Author Report Share Posted March 22, 2019 Hi Jochem Thanks for the compliment, I did most the work myself, got a local chap who I know to skim my head as I don’t have machine large enough myself and after we put the valve guides in he remachined the valve seats. I did all the porting. I used the profile I got out the book tuning Triumphs over 1300cc. I'm hoping to get it on the rolling road this summer. Quote Link to post Share on other sites
tr graham Posted March 22, 2019 Report Share Posted March 22, 2019 Marcel i had similar problems with a car I purchased , somebody had reworked the head then re assembled the valves with lightweight caps , I found that the springs had worn the caps ,and the residue was in the valve guide , and eventually the valves jammed open. graham Quote Link to post Share on other sites
Waldi Posted March 24, 2019 Report Share Posted March 24, 2019 Hi Marcel, that looks like a nice engine bay:) If you have bronze valve guides, make sure they have sufficient clearance to the valve stem. I reamed my bronze guides myself, but when Andreas (Triump V8 on this forum) checked them he felt the were to tight, so I followed his advice (off course) and we reamed them a bit further. Waldi Quote Link to post Share on other sites
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