RobDob Posted April 4, 2012 Share Posted April 4, 2012 Hi, I have a 88 with 178k on the engine which as far as i know hasnt had a top end rebuild. Engine doesnt smoke or use any excessive oil and pulled well. I decided last weekend that i would check the valve clearances just as a matter of course. Before this the engine didnt really sound very tappety and sounded pretty good. After strictly adhereing to the prescribed procedure (as found on Pelican / Haynes manual etc.. using TDC method and Z1 Timing on crank) i find that the engine is very tappety / noisy. So, took the valve covers off again to check and all seems fine when checking againt know procedure, however i have noticed that even when setting the valve clearance to the right amount say on no 1 cylinder, if you then rotate the crank a bit further from the adjust Number 1 valve TDC to move to the next valve, then the previous valve clearance i.e. Number 1 cylnder then becomes bigger i.e. more slack and out of tolerance (quite significantly). I used number 1 Cylinder as an example here i think they all do it but mainly Cylinder 2 and 5 are the worse... Is this usual? Im confused by it. When i first checked the clearances i did think that some of the valves were tight... Thanks, Rob Link to comment Share on other sites More sharing options...
R2D2 Posted April 4, 2012 Share Posted April 4, 2012 Hi Rob Welcome to the forum. Are you sure you were at TDC? I.e. was the distributor rotor also pointing to cylinder no. 1 mark when you were at Z1 on the pulley? Cheers Nathan Link to comment Share on other sites More sharing options...
RobDob Posted April 4, 2012 Author Share Posted April 4, 2012 Hi Nathan, Thanks for your reply. Yes i made sure that the rotor arm in the dist was pointing to cylinder no 1 and z1 mark on the crank was aligned. There are two marks on my pulley, one says z1 and one slightly before this which is BTDC, i used z1. I'm stumpted at the moment. Thanks, Rob Link to comment Share on other sites More sharing options...
jevvy Posted April 5, 2012 Share Posted April 5, 2012 As I understand it a bit tappy is better than totally quiet but obviously not too tappy. Perhaps yours has been too tight for a while and now you have the correct gaps you can hear the tap? The gaps can only be checked when the crank is in the correct position for that valve - as soon as you move it(even a smidge) then the gap size is irrelevant. You might want to have a search for the "backside method" as it gives you another way to check your measurements during the process. Good luck and welcome to the forum Link to comment Share on other sites More sharing options...
Nige Posted April 5, 2012 Share Posted April 5, 2012 Is this the first time you have done the clearance? Was the engine proper stone cold when you checked the clearances? Link to comment Share on other sites More sharing options...
R2D2 Posted April 5, 2012 Share Posted April 5, 2012 Hi Nathan, Thanks for your reply. Yes i made sure that the rotor arm in the dist was pointing to cylinder no 1 and z1 mark on the crank was aligned. There are two marks on my pulley, one says z1 and one slightly before this which is BTDC, i used z1. I'm stumpted at the moment. Thanks, Rob Hi Rob The one slightly before TDC is to be ignored - you were correct to use Z1. As Jev says the backside method is at the very least a good sanity check http://www.pelicanparts.com/techarticles/9...valveadjust.htm Make sure you've got the right gauge feelers though. Good luck Nathan Link to comment Share on other sites More sharing options...
RobDob Posted April 5, 2012 Author Share Posted April 5, 2012 Hi Guys, Thanks for the replys. Jevvy, I think they were a little too tight to statr with to be honest. I checked a couple of real offenders (noticably cylinders 5 and 2, exausht) and they were quite tight when i first checked them. Its very tappety now, was no where near as bad before i did the adjustment. r.e. "as soon as you move it(even a smidge) then the gap size is irrelevant", i thought that with the timing set to TDC then this is the point where the rocker would have the most play hence why you set it here. The rest of the duration of the cam would then put the rocker under load and hence no gap at all.. Nige, it is the first time for me, the engine was completely cold, left it overnight to be sure. Nathan, thanks for the info on the backside method, seems like a better approach to me. Will give that a go... Will keep you posted. Thanks, Rob Link to comment Share on other sites More sharing options...
sladey Posted April 5, 2012 Share Posted April 5, 2012 Don't forget the psychological effect of intently listening to the engine - they are noisy engines and if you're listening for an elephant banging around inside you'ld probably be able to pick it out. once you've done something like this it's hard not to be hyper-sensitive to listening to what you've done. I also wrote some notes after I did it for the second time - dunno if they are of any use http://www.ddk-online.com/phpBB2/viewtopic...p;hilit=tappets Link to comment Share on other sites More sharing options...
RobDob Posted April 7, 2012 Author Share Posted April 7, 2012 Hi Guys, Figured out what my problem was. I was reading the cylinder order the wrong way round! So what i thought was cylinder 1 was in fact cylindet 6... What a donkey. Anyway, i adjusted them this morning and it sounds great now. Thanks for your input. Rob Link to comment Share on other sites More sharing options...
sladey Posted April 16, 2012 Share Posted April 16, 2012 Better to be a donkey and solve the problem than have a more serious problem - well done on sorting it out Link to comment Share on other sites More sharing options...
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