iain Posted January 15, 2017 Author Report Share Posted January 15, 2017 (edited) Hi Iain, are you saying 6 lobes are fairly central to the follower bores and two are off-set by apprx 1/3. Can you compare with an old cam? Roger Hi Roger yes that's correct. Won't be able to compare camshafts until I take the front off the car and get the cam out,...Or maybe I can by laying it over the top. Will report back. Deep joy Iain Edited January 15, 2017 by iain Quote Link to post Share on other sites
Tom Fremont Posted January 15, 2017 Report Share Posted January 15, 2017 Hi Iain, A well known cam supplier told me TR cam lobes are offset from the tappet centreline and require the use of flat tappets, not crowned ones. The visual difference in these is so slight that you may not be able to tell the difference except by smearing a very slight amount of oil on the bottoms and sticking them together. They will adhere if flat, and won't if crowned. You could try this experiment with a pair whose bottoms are yet unblemished. Crowned tappets will wipe the lobes of TR cams in as little as 150 miles ( not wipe off, but pit noticeably ). Still, I don't think this will produce a knocking sound. The only sound I recall from wiped lobes was a rattling at ~ 3000 rpm. Cheers, Tom Quote Link to post Share on other sites
iain Posted January 15, 2017 Author Report Share Posted January 15, 2017 Hi Tom I read and noted this comment from your earlier post....They do stick together, with the exception of the one that has wiped. Cheers Iain Quote Link to post Share on other sites
Chilliman Posted January 15, 2017 Report Share Posted January 15, 2017 Another question for the knowledgeable, should the cam lobes be central to the bore of the cam followers? Iain, that was always something that concerned me when building mine but I've checked numerous good quality cams and they all sit with the bores offset to the cam lobes, don't ask me why but some lobes appear more offset than others? It's good to know the problem at last but was it really just poorly machined tappets causing all that grief. I'm looking forward to the pics. Don't forget I've got good spare stuff to compare with if you need it....... Quote Link to post Share on other sites
iain Posted January 15, 2017 Author Report Share Posted January 15, 2017 Hi John I am sure you and Tom are right re the off centre cam lobes I have just had a look at the old one and it seems to be the same. I shall have a discussion with the supplier tomorrow. All parts have come from the same place so that should help and I used their preferred machine shop. Cheers Iain Quote Link to post Share on other sites
Guest ntc Posted January 15, 2017 Report Share Posted January 15, 2017 Iain Ask them how old the parts was. Quote Link to post Share on other sites
iain Posted January 15, 2017 Author Report Share Posted January 15, 2017 (edited) Iain Ask them how old the parts was. Hi Neil I am guessing that at some point in the past there has been a problem? With the cam or the followers? Cheers Iain Edited January 15, 2017 by iain Quote Link to post Share on other sites
Guest ntc Posted January 15, 2017 Report Share Posted January 15, 2017 Hi Neil I am guessing that at some point in the past their has been a problem? With the cam or the followers? Cheers Iain Iain That is a understatement to say the least. Quote Link to post Share on other sites
iain Posted January 15, 2017 Author Report Share Posted January 15, 2017 Hi Neil Still not sure if that's the followers or the cam? Please can you clarify? Ta very much Iain Quote Link to post Share on other sites
Guest ntc Posted January 15, 2017 Report Share Posted January 15, 2017 Hi Neil Still not sure if that's the followers or the cam? Please can you clarify? Ta very much Iain Both alas ask how old ? and demand to see proof Quote Link to post Share on other sites
iain Posted January 15, 2017 Author Report Share Posted January 15, 2017 Cheers Neil Any clues as to time frame of these duff bits......Sorry to keep asking but forwarned is forearmed. Many thanks Iain Quote Link to post Share on other sites
Guest ntc Posted January 15, 2017 Report Share Posted January 15, 2017 Iain To protect all partys if it is older stock ie 3 years or above,many have fell foul of both been made of cheese,fact. Quote Link to post Share on other sites
iain Posted January 15, 2017 Author Report Share Posted January 15, 2017 Oh.......That's a bit of a bummer. Cheese would be harder than these. Iain Quote Link to post Share on other sites
Guest ntc Posted January 15, 2017 Report Share Posted January 15, 2017 Iain I hope this not the case for you,I had one last 12 miles there has been many posts in the past. Quote Link to post Share on other sites
iain Posted January 16, 2017 Author Report Share Posted January 16, 2017 (edited) Well not a lot of progress. The followers run smoothly in the bores but for one reason or another it would appear some have stopped rotating and worn badly......They would with no proper lubrication. If these side drilled followers stop rotating you are clearly doomed as lubrication will only be at the one point. The original followers would have prevented this as the bucket fills with oil and overflows in to the bore. The bore is clearly designed with a reservoir at the high point of followers travel,it's sleeve is 2-3 mm wider to allow some accumulation of oil. Iain PS These followers also have a bevelled edge only slight but why? Edited January 16, 2017 by iain Quote Link to post Share on other sites
RogerH Posted January 16, 2017 Report Share Posted January 16, 2017 Hi Iain, I wouldn't panic about the side drilled holes in the followers. I do not think they are there for follower lubrication. Everywhere inside the engine gets covered in oil mist. I am more convinced that the hole allows oil to flow down and get onto the follower/cam lobe contact face. Roger Quote Link to post Share on other sites
iain Posted January 16, 2017 Author Report Share Posted January 16, 2017 Hi Roger Fair point. I'm am struggling to find an answer to the none rotation. The followers are identical dimensions to the originals 23.80mm in diameter with no variance so why did they stop rotating one can only guess at a lack of lubrication. Given that the oil pump is plastering the barn let alone the engine bay when the lid is off I find this hard to explain. Iain Quote Link to post Share on other sites
Guest ntc Posted January 16, 2017 Report Share Posted January 16, 2017 You only need the holes on a wild cam for racing or rally and the valve clearence is big so the noise don't matter Quote Link to post Share on other sites
Motorsport Mickey Posted January 16, 2017 Report Share Posted January 16, 2017 As far as I remember the holes do a neat job of allowing the "foot" of the cam follower to drop off when they instigate a crack which transfers radially around the circumference and meets the other side ! Mick Richards Quote Link to post Share on other sites
iain Posted January 16, 2017 Author Report Share Posted January 16, 2017 That's neat! Not. So who's followers to use? Iain Quote Link to post Share on other sites
GT6M Posted January 16, 2017 Report Share Posted January 16, 2017 I did say they would be dooing this seen it loadsa times befoer me own engines included that why i said it be this Bit of a pita for ye though M Quote Link to post Share on other sites
iain Posted January 16, 2017 Author Report Share Posted January 16, 2017 Cheers Marcus Yup, I was just trying to avoid the inevitable.:-) Iain Quote Link to post Share on other sites
Guest ntc Posted January 16, 2017 Report Share Posted January 16, 2017 Iain Some pics might help ,I reckon the cam and followers are wrong match.Did you find out how old? Quote Link to post Share on other sites
iain Posted January 16, 2017 Author Report Share Posted January 16, 2017 (edited) Hi Neil Cam is a Kent Fast Road. Followers I need to check with supplier either phophated or tufrided side drilled. As recommended by the supplier of the cam. Don't want to name names. Iain Edited January 16, 2017 by iain Quote Link to post Share on other sites
Guest ntc Posted January 16, 2017 Report Share Posted January 16, 2017 Good idea,you have PM Quote Link to post Share on other sites
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