AidanT Posted December 26, 2020 Author Report Share Posted December 26, 2020 7 minutes ago, Pete Lewis said: are the other two allen key socket cap bolts ?? thats the harmonic damper ring bonding Hi Pete No they are just loose nuts, left them on so I have a historic pic of what bolts nuts and screws go in which hole! Determined to put in back together the same way it came apart Link to comment Share on other sites More sharing options...
Colin Lindsay Posted December 26, 2020 Report Share Posted December 26, 2020 15 minutes ago, AidanT said: Bolt out but to next problem. I assume the timing cover should be all bolts but.. please refer to the pic. Any ideas how to move these? The slots aren't great and they are about 15mm across, my biggest screw driver won't touch them Be careful with them. They're hard to replace. If you need replacements some suppliers will try to fob you off with Philips-head versions stating that is all that is available but search for 5/16 x 3/8 pan head slotted machine screws and you'll find them. Link to comment Share on other sites More sharing options...
AidanT Posted December 26, 2020 Author Report Share Posted December 26, 2020 14 minutes ago, clive said: You need bigger screwdriver! And ideally a hammer-through type Clive I've got an impact driver, never thought of that- just need an appropriate driver head - off to eBay! Link to comment Share on other sites More sharing options...
Anglefire Posted December 26, 2020 Report Share Posted December 26, 2020 46 minutes ago, AidanT said: Clive I've got an impact driver, never thought of that- just need an appropriate driver head - off to eBay! I used an impact driver - mine (some 30years old) came with several bits including slotted and cross head. Link to comment Share on other sites More sharing options...
AidanT Posted December 26, 2020 Author Report Share Posted December 26, 2020 Well sometimes I forget what I have in the tool chest! Manual impact driver and a load of heads including wide flat heads TADAAA! Ok so opinions please on the following pictures. I thought the tensioner from all the comments above was going to be scary!! Not a bit of curved spring metal on the inside of the cover!!! Got me there guys!!! Btw chain moves some 18mm on total left to right it feels nice and smooth when you run your finger down the side Link to comment Share on other sites More sharing options...
Pete Lewis Posted December 26, 2020 Report Share Posted December 26, 2020 its been apart before the centre dot timing marks are from a previous world the chain looks fine . but you need to read up about cam timing as the 4 holes in the sprocket allow 1/4 tooth incremental adjustment and getting pistons and cam lobes at top dead centre is not a dark art but is very close . you may need to ask about a piston stop and a dial indicator to get it all spot on on rebuild or use the large rocker equal gap and feelers method as in the WSM. Pete Link to comment Share on other sites More sharing options...
Colin Lindsay Posted December 26, 2020 Report Share Posted December 26, 2020 4 minutes ago, Pete Lewis said: its been apart before the centre dot timing marks are from a previous world Same as my GT6 engine, a punched dot along a straight line. Link to comment Share on other sites More sharing options...
NonMember Posted December 26, 2020 Report Share Posted December 26, 2020 As Pete says, the chain and gears look fine. The tensioner is showing some wear but if it's original (or of same quality) it will probably outlast a lot of the available new ones. It would benefit from a clean and there's a spot of surface rust on the cover that wants scrubbing off. Link to comment Share on other sites More sharing options...
AidanT Posted December 26, 2020 Author Report Share Posted December 26, 2020 Thanks all In terms of timing a gauge with a magnetic base doesn't seem too expensive When removing the cam sprocket, how many ways does that re-fit? So are there just two places to bolt to, so you can only get it right or 180 out?, or can it only go back one way??? Thanks Link to comment Share on other sites More sharing options...
Anglefire Posted December 26, 2020 Report Share Posted December 26, 2020 You can flip the single chain sprockets over too - which gives you several permutations to get down to the fine angles possible. Link to comment Share on other sites More sharing options...
thescrapman Posted December 26, 2020 Report Share Posted December 26, 2020 Teeth on cam sprocket look a little pointy to me. but they do look even each side Link to comment Share on other sites More sharing options...
Iain T Posted December 26, 2020 Report Share Posted December 26, 2020 You can find tdc using a piston stop. I'm sure there are some instructions on the forum or guggle it. Doesn't require a dial gauge and possibly more accurate. Iain Link to comment Share on other sites More sharing options...
Pete Lewis Posted December 26, 2020 Report Share Posted December 26, 2020 you need a dial indicator if you want to connect the chain and you dont now if the lobe is at tdc theres a lot of rotation either side of the cam lobe with no change in lift so you use a DTI and big protractor disc on the cam rotate cam to give a known lift mark protractor turn cam other way to get the same lift marl the disc tdc is halfway between the two marks doing the same on a crank is easy if you bolt a home made stop on the block face which will block the piston rising fully again use big disc and mark the stopped position in both directions halfway is TDC the 4 holes in the sprocket each pair gives 1/4 tooth turn the sprocket over and the same applies you get another pair of 1/4 tooth so the 4 positions give a full 1 tooth adjustment you can do all the above tests and find the dot marks are spot on or as normal as pevious work may not have any of the correct settings and they are actually hopelessly miles out as you are going to a lot of trouble and asking lots its an area you need to get your head round its pretty easier than it reads there can be a TDC mark on the flywheel but like the front that needs the rear plate and F wheel fitted same as TDC pointer is only on the timing cover and thats not fitted either Pete Link to comment Share on other sites More sharing options...
AidanT Posted December 27, 2020 Author Report Share Posted December 27, 2020 10 hours ago, Pete Lewis said: so you use a DTI and big protractor disc Is this DIY or can you buy one? Think I'd be pretty crap at something like that though maybe a print off the web backed by a bit of card?? Link to comment Share on other sites More sharing options...
Colin Lindsay Posted December 27, 2020 Report Share Posted December 27, 2020 There are a lot of them online, just search 'timing gear protractor' or the like, but most of them seem to be purchase items and I'm not sure how accurate they'd be if translated to a print version. It's bound to be do-able if you find the proper template; someone must have uploaded one. Link to comment Share on other sites More sharing options...
AidanT Posted December 27, 2020 Author Report Share Posted December 27, 2020 Hi Thanks Colin but I think I have my head around this at least for the crank- it could actually be blank as all that's needed is along with the gauge is to mark the disk at the two points the gauge shows the max height and split the markings in the middle- that's tdc How do you get the gauge to reach the cam lobe? And which one for tdc? Link to comment Share on other sites More sharing options...
NonMember Posted December 27, 2020 Report Share Posted December 27, 2020 16 minutes ago, AidanT said: How do you get the gauge to reach the cam lobe? And which one for tdc? With the crank at TDC No. 1 firing, the valves on No. 6 should be "on the rock". What this means is that the exhaust valve is still closing when the inlet starts opening, so the TDC position is when they're equally open. To measure this, the book method is to fit the valve gear and set an artificial tappet clearance, to plainly identify the fully closed position. Then rotate until you can measure both valves equally lifted (or the clearance equally reduced, if that's easier). You could do the equivalent with two dial gauges and just the cam followers fitted. I'm sure somebody here will have a cunning trick using a few pieces of string... Link to comment Share on other sites More sharing options...
Anglefire Posted December 27, 2020 Report Share Posted December 27, 2020 I created a protractor in acad - I've attached the pdf version. Just print it out on stiff paper or card. Cam Timing.pdf 1 Link to comment Share on other sites More sharing options...
AidanT Posted December 27, 2020 Author Report Share Posted December 27, 2020 Thanks for the pdf Just thinking about the cam, surely one of the other lobes on the cam must be at the top when the crank is at TDC??? Link to comment Share on other sites More sharing options...
Pete Lewis Posted December 27, 2020 Report Share Posted December 27, 2020 just fit the cam followers and you can measure lift from the top of the block might need anything stable dropped in the follower as an extension pete if you dont have a dial indicator wait till the heads on and use the WSM method of a wide but equal tappet gap ..its quite easy to do just read the book a couple of times to get the gist of what you are doing all you need is the crank accuratley ( have alook at the back plate and f wheel for tdc marks ) at TDC and a set of feelers Link to comment Share on other sites More sharing options...
DanMi Posted December 27, 2020 Report Share Posted December 27, 2020 I used a second cam follower upside down and 2 dial gauges, you need to find the point when both cam lobes of no4 (4 cyl) have equal lift one opening one closing and the value doesn't matter. At that point the crank needs to be no1 tdc. I wouldn't use the marks on the wheel as there is about 5 degrees of movement on the bolt holes. I would if doing it again do the cam timing with only no1 piston in as that will make turning the crank easier. This is assuming a standard camshaft. Link to comment Share on other sites More sharing options...
Pete Lewis Posted December 27, 2020 Report Share Posted December 27, 2020 Hi Dan hence many make a piston stop it all depends on what state of build you have, in bits, part build ,,,,ready to run with no timing cover fitted there are few options apart from put the cover on off on off Pete Link to comment Share on other sites More sharing options...
DanMi Posted December 27, 2020 Report Share Posted December 27, 2020 Agreed Pete but I meant not use the stamped marks on the cam wheel, from previous alignment, without measuring the timing as the wheel on the cam has quite a lot of rotational movement from the bolt holes. I just made up a pointer for the crank, but using the flywheel would be easier Link to comment Share on other sites More sharing options...
Iain T Posted December 27, 2020 Report Share Posted December 27, 2020 On 06/04/2020 at 10:14, JohnD said: "So, seeking for further amusement" I reviewed my files and found this: This piston stop is easily made from a piece of square/rectangular tube, or some angle iron. It will allow you to find more accurately the TDC than is possible with a dial guage. If you want to do the job without removing the head studs, then two lengths of tube with washers on top, will secure the stop in place over the studs. Jphn PS "Seeking for further amusement" Stanley Holloway, may amuse you. His version of "Albert and the Lion" is famous, and he did many others, for instance "Sam Small" Post from JohnD showing a home made piston stop. Iain Link to comment Share on other sites More sharing options...
Roger K Posted December 27, 2020 Report Share Posted December 27, 2020 Interested to know how that is more accurate than using a dial gauge? Link to comment Share on other sites More sharing options...
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