Davemate Posted October 18, 2015 Share Posted October 18, 2015 I need to know in "simple English" how to install a cam into a short blockI'm picking up my shirt block on Tuesday and I'm hoping to fit the cam,oil pump and fit the sump so I can fit the bottom end back into the car. The head and all the other bits will be done later(soon as time allows)I've read my thick workshop manual but it only gives instructions with the head fitted, ie fit cam with crank set at 45 degrees before TDC and then once head is fitted you set the tappets and aligne everything up.Is there another way to set the cam up as I want to fit the timing cover and fit things up without the head being onHope I'm making sence ! Quote Link to comment Share on other sites More sharing options...
RobPearce Posted October 18, 2015 Share Posted October 18, 2015 It's certainly possible (I did it myself not long ago on Tessa). There was a thread on here not long ago about setting cam timing. The usual rule is to find the point where the valves are "on the rock" - exhaust closing and inlet opening. This is easier than identifying peaks or troughs, and also lines up with a convenient crank position - TDC.So the question is how to find that balance point without the head fitted. And the answer is very nearly the same as it would be with the head. Just pop the tappets and pushrods in. Press down on the pushrods with two fingers and rotate the cam until you can feel the inlet lift. Continue until the exhaust stops dropping then rotate back until it begins to lift. Half way between that and the first point is the correct alignment. Quote Link to comment Share on other sites More sharing options...
nang Posted October 19, 2015 Share Posted October 19, 2015 I made up a couple of dummy short pushrods exactly the same length which I fitted inside the cam followers. Set up dial gauge and turned camshaft until I got equal height. (Hope this makes sense)Tony. Quote Link to comment Share on other sites More sharing options...
JohnD Posted October 19, 2015 Share Posted October 19, 2015 The technique is known as "Equal lift on overlap", which may help you find more detailed desription.What is omitted above is that the equal lift must be on the FOURTH cylinder when it and No.1 are at TDC, IE not on the fiiring stroke but at the end of one 4 stroke cycle and the beginning of the next, when the opening of exhaust and inlet overlap.John Quote Link to comment Share on other sites More sharing options...
JohnD Posted October 19, 2015 Share Posted October 19, 2015 The technique is known as "Equal lift on overlap", which may help you find more detailed desription.You don't need equal length dummies - that would be precision enginering of an order foreign to Triumphs!You need to be able to measure the lift on two valves, or cam followers, hence the dummies, so dummies more or less equal are convenient.I use two pieces of wooden dowel, wrapped with tape so that they are a sliding fit in the follower.What is omitted above is that the equal lift must be on the FOURTH cylinder when it and No.1 are at TDC, IE not on the fiiring stroke but at the end of one 4 stroke cycle and the beginning of the next, when the opening of exhaust and inlet overlap.John Quote Link to comment Share on other sites More sharing options...
piman Posted October 19, 2015 Share Posted October 19, 2015 Hello John, not on a six cylinder engine, it needs to be the sixth cylinder.Alec Quote Link to comment Share on other sites More sharing options...
JohnD Posted October 19, 2015 Share Posted October 19, 2015 But the fourth cylinder on a four cylinder engine. Which, as far as I can tell is what the OP was asking about .JohnGods teeth you try to help, and ... Quote Link to comment Share on other sites More sharing options...
JohnD Posted October 19, 2015 Share Posted October 19, 2015 And, Davemate, Richard Feynman was challenged by a journalist that surely such a great physicist and teacher could explain quantum theory to the "average person"."If I could explain it to an average person it wouldn't have been worth the Nobel Prize"Thank goodness "Equal lift" is nowhere in that league, but Feynman also said in response to similar question, that anyone who didn't understand something needed to study more. Do some more reading about it, and come back if you have a problem. And, I hope, when you have tackled it and succeeded!JOhn Quote Link to comment Share on other sites More sharing options...
Davemate Posted October 19, 2015 Author Share Posted October 19, 2015 And I was hoping to just line the dots up 🤔 Quote Link to comment Share on other sites More sharing options...
RobPearce Posted October 19, 2015 Share Posted October 19, 2015 Quoted from Davemate And I was hoping to just line the dots up 🤔 If the dots were made on that pair of pulleys, while fitted to the same crank and cam you're fitting, when the valve timing was correct, then you probably can. However, you also need to know which pair of bolt holes were used and which way up the cam was... and the easiest way to confirm that is probably to try setting the cam to "equal lift". Quote Link to comment Share on other sites More sharing options...
piman Posted October 19, 2015 Share Posted October 19, 2015 Hello John,"Which, as far as I can tell is what the OP was asking about ."Well I assumed it was a six as that is what Dave has been working on lately. You must admit that your post would be very misleading on a six cylinder engine?Dave, it really is not that difficult, At TDC the firing stroke cylinder the two cams will be as an inverted 'Vee' looking end on at the cam and the opposite TDC cylinder will be a 'Vee',what you are doing is to get equal height to both ends of the Vee, and the crank at TDC. Alec Quote Link to comment Share on other sites More sharing options...
JohnD Posted October 19, 2015 Share Posted October 19, 2015 Dave,"Is there another way to set the cam up"? you asked.We told you, I got scolded (Pax, piman!) and you're fed up!I've written up ELoO several times, so have a look here - http://www.tr-register.co.uk/forums/index.php?/topic/13546-uprated-camshaft-timing-settings/OR here: http://sideways-technologies.co.uk/forums/index.php/topic/6120-cam-install/John Quote Link to comment Share on other sites More sharing options...
Davemate Posted October 20, 2015 Author Share Posted October 20, 2015 Thanks chaps for all you info Today I fitted and timed the cam up, to my total surprise my order of a new set of followers arrived from mr witor (only ordered them yesterday) so I could fit them and insert the two pushrods into number six pot. I got both pushrods rocking, set the crank to TDC and popped the chain on So I ended up doing it properly Don't know what I was worried about Quote Link to comment Share on other sites More sharing options...
Trolleybus Posted October 20, 2015 Share Posted October 20, 2015 Here is another TDC method. Cam lift at TDC.Establish top dead centre, Place a pushrod in the cam follower and mount a dial indicator so it is in the same plane as the pushrod.I used number one intake.Make sure the cam follower is on the heal (bottom) of the lobe and zero the dial indicator.Now turn the camshaft in the same direction as the crankshaft until the lift at TDC is achieved.My cam card from the supplier stated 1.143mm.It is a 28 Btdc 66.5 Abdc on intake cam Quote Link to comment Share on other sites More sharing options...
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