Pete Lewis Posted August 17, 2023 Report Share Posted August 17, 2023 you can write a private e mail from the email tab in you profile pete Link to comment Share on other sites More sharing options...
nicrguy1966 Posted August 17, 2023 Author Report Share Posted August 17, 2023 26 minutes ago, JohnD said: Believe it or not, the Post Office does provide an excellent service, even to those parts of the UK that do not speak 'Received English'. John I dread to think how much it would cost to post a GT6, even second class Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 17, 2023 Report Share Posted August 17, 2023 (edited) you can send a private e mail from this site either from your profile page or the envelope icon on the top blue header or click on the members avatar to get the e mail Pete Edited August 17, 2023 by Pete Lewis Link to comment Share on other sites More sharing options...
JohnD Posted August 17, 2023 Report Share Posted August 17, 2023 Nicr, I can't test your entire car. much as I'd like to. Post me your crank pulley, which weighs 1600 grams and would cost (with less than 400 grams of cardboard) a bit over £6 First Class . John Link to comment Share on other sites More sharing options...
nicrguy1966 Posted August 17, 2023 Author Report Share Posted August 17, 2023 2 hours ago, JohnD said: Nicr, I can't test your entire car. much as I'd like to. Post me your crank pulley, which weighs 1600 grams and would cost (with less than 400 grams of cardboard) a bit over £6 First Class . John That makes a lot more sense than my idea! Hopefully it will not come to that. First I need to inspect the pulley, then try setting the crankshaft to TDC then see what the timing indicator position is. After that, maybe I'll think about removing the pulley, but it's something I'd prefer to avoid, especially as the car is currently drivable with its weird timing advance setting. Link to comment Share on other sites More sharing options...
JohnD Posted August 17, 2023 Report Share Posted August 17, 2023 Indeed! Good plan! Link to comment Share on other sites More sharing options...
nicrguy1966 Posted August 19, 2023 Author Report Share Posted August 19, 2023 (edited) Update! I did a few tests this morning. 1) The timing marks seems fixed firmly to the pulley. No way I could move them in either direction, even with a screwdriver wedged into the TDC marker. 2) With the plug out of cylinder 1, I could easily feel the piston position with a screwdriver and although it doesn't move much at the top of the stroke, I could easily detect movement around 10 degrees before and after the TDC mark. So it seems the TDC mark is in the right place. 3) This time I took a photo of the strobe at idle (a smooth 650rpm). The mark is showing more than 20 degrees BTDC. 4) When rev'ed to 2000rpm, the timing mark is so far advanced, it's not visible from the angle the photo was taken at, so maybe 40 degrees BTDC! Even when set 'by ear' and running smoothly,I have noticed a lack of power at high revs and open throttle (e.g. accelerating from 50 to 70 in top gear). 5) When removing spark plug 1, I noticed the mixture was a little rich. Nothing too extreme, but worth noting. I would have expected a lean mixture given the K&N air filters. So that's all the latest news. Any idea what to try next? Edited August 19, 2023 by nicrguy1966 Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 19, 2023 Report Share Posted August 19, 2023 cam timing or dodgy strobe ?? Link to comment Share on other sites More sharing options...
nicrguy1966 Posted August 19, 2023 Author Report Share Posted August 19, 2023 1 hour ago, Pete Lewis said: cam timing or dodgy strobe ?? I don't think it's a dodgy strobe as whenever anyone tries to tune the car with a strobe it ends up awful, not just me. I assume I'd have to remove the timing chain cover to check the cam timing? Link to comment Share on other sites More sharing options...
johny Posted August 19, 2023 Report Share Posted August 19, 2023 You could do it from the cam sprocket marks or the rocking valve method as described in the workshop manual which uses the position of cylinder 1 inlet and outlet rockers at TDC to indicate correct cam timing... Link to comment Share on other sites More sharing options...
nicrguy1966 Posted August 19, 2023 Author Report Share Posted August 19, 2023 35 minutes ago, johny said: You could do it from the cam sprocket marks or the rocking valve method as described in the workshop manual which uses the position of cylinder 1 inlet and outlet rockers at TDC to indicate correct cam timing... I'll do some research! Link to comment Share on other sites More sharing options...
RedRooster Posted August 19, 2023 Report Share Posted August 19, 2023 1 hour ago, johny said: You could do it from the cam sprocket marks or the rocking valve method as described in the workshop manual which uses the position of cylinder 1 inlet and outlet rockers at TDC to indicate correct cam timing... What he says. RR Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 19, 2023 Report Share Posted August 19, 2023 yes can be done from the rockers no need to strip anything down just need feelers 1/2"af spanner and screwdriver follow the manual or we can spell it out if thats helpfull Pete Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 19, 2023 Report Share Posted August 19, 2023 all this but why????? has the car had a long standing problem or has a problem arrived out the blue ???? {Pete Link to comment Share on other sites More sharing options...
nicrguy1966 Posted August 19, 2023 Author Report Share Posted August 19, 2023 (edited) 30 minutes ago, Pete Lewis said: all this but why????? has the car had a long standing problem or has a problem arrived out the blue ???? {Pete It's been a problem I've been ignoring for years, but something's not right and if I can fix it, I'd like to. A problem is still a problem even if it's old. The first job is to work out why the timing is so extreme. Edit: If I fix it, I'm hoping for better performance or better MPG, or maybe both. Edited August 19, 2023 by nicrguy1966 Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 20, 2023 Report Share Posted August 20, 2023 a vacuum gauge on the inlet manifold gives a good indication of timing and general running needs an idle reading around 18 -21 ins /hg doing a simple rocker cam timing test is worth reading up on as the chain wears the cam timing gets later but that wont upset ign as you just turn the dizzy to accomodate the changes the tensioner is on the slack side of the chain so as the links and pins wear the drive side gets ...longer and cam gets later all these things help if performance is diminishing Pete Link to comment Share on other sites More sharing options...
nicrguy1966 Posted August 21, 2023 Author Report Share Posted August 21, 2023 On 19/08/2023 at 17:35, johny said: You could do it from the cam sprocket marks or the rocking valve method as described in the workshop manual which uses the position of cylinder 1 inlet and outlet rockers at TDC to indicate correct cam timing... I only have the Haynes Manual, not the official Workshop Manual, and as far as I can tell, it doesn't contain anything about checking the cam timing using the "rocking valve method". Do you know if a description of this has ever been published online? Link to comment Share on other sites More sharing options...
johny Posted August 21, 2023 Report Share Posted August 21, 2023 Ah you need the free to download bible kindly offered at vitessesteve.co.uk 1 Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 21, 2023 Report Share Posted August 21, 2023 basic rules are you turn engine so rockers 11 &&12 are on the rock/in balance (one going down one coming up) set rockers 1 &2 tappets to 0.050" turn engine to align TDC for no1 on compression and then measure the tappet gaps on the wide setting doesnt matter what the gap is so long as they should both be the same /equal . any variance needs a bit of chain/sprocket twiddling on another day the cam sprocket has 4 holes and the sprocket can be turned over this will give each fixing at 1/4 tooth adjustments increments. so with a good pair of glasses and six hands its quite easy and adjustable if its needed Pete Link to comment Share on other sites More sharing options...
nicrguy1966 Posted August 21, 2023 Author Report Share Posted August 21, 2023 1 hour ago, johny said: Ah you need the free to download bible kindly offered at vitessesteve.co.uk Downloaded, and I've found the section on checking the cam timing. This will be very useful in the future, not just while I'm scratching my head over timing advance. Thanks for the link. Link to comment Share on other sites More sharing options...
nicrguy1966 Posted August 21, 2023 Author Report Share Posted August 21, 2023 43 minutes ago, Pete Lewis said: basic rules are you turn engine so rockers 11 &&12 are on the rock/in balance (one going down one coming up) set rockers 1 &2 tappets to 0.050" turn engine to align TDC for no1 on compression and then measure the tappet gaps on the wide setting doesnt matter what the gap is so long as they should both be the same /equal . any variance needs a bit of chain/sprocket twiddling on another day the cam sprocket has 4 holes and the sprocket can be turned over this will give each fixing at 1/4 tooth adjustments increments. so with a good pair of glasses and six hands its quite easy and adjustable if its needed Pete Another project for next weekend! Even if this doesn't reveal anything wrong, it's a good excuse to check and adjust the tappets, which haven't been done for a while. As always, I'll report back once I've done the work and washed my hands! Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 21, 2023 Report Share Posted August 21, 2023 (edited) general tappet adjustments are use rule of 13 and 0.010" on a cold engine rule 13 1 down set 12 10 down set 3 etc if the rocker pads are worn then feelers will bridge the wear and give a false feel to the feeler fit Pete Edited August 21, 2023 by Pete Lewis Link to comment Share on other sites More sharing options...
nicrguy1966 Posted August 21, 2023 Author Report Share Posted August 21, 2023 3 minutes ago, Pete Lewis said: general tappet adjustments are use rule of 13 and 0.010" on a cold engine rule 13 1 down set 12 10 down set 3 etc if the rocker pads are worn then feelers will bridge the wear and give a false feel to the feeler fit Pete I had a reconditioned engine fitted about 15 years ago (with hardened valve seats for unleaded petrol), so there shouldn't be 50 years of wear to worry about, and those 15 years haven't been high mileage. I wonder if my timing issues originate from that engine swap? I probably drove it for several years trouble free without ever checking the ignition timing. Link to comment Share on other sites More sharing options...
Pete Lewis Posted August 21, 2023 Report Share Posted August 21, 2023 hardened seats only go on the exhaust seats thats fine but has nothing to do with the rocker pad that wears where it rubs the head of the valve stem and makes a groove in the rocker pad this makes a normal feeler a poor fit at judging the real gap Kickadjust make a ratchet socket and driver but they are fiddly an need an accurate gap in the first to set up the clicks ...pretty useless but a good idea of sorts wire pin gauges are best but try to find them ....no hope have fun keep on this one day all will be revealed ....well !!! Pete Link to comment Share on other sites More sharing options...
Ian Foster Posted August 21, 2023 Report Share Posted August 21, 2023 2 hours ago, nicrguy1966 said: I had a reconditioned engine fitted about 15 years ago It is possible that the cam was installed incorrectly. The check procedure will show if it is out. Ref Pete's question above, is this a new or longstanding issue? Ian Link to comment Share on other sites More sharing options...
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