jk136 Posted March 15, 2010 Share Posted March 15, 2010 Ive just done a head gasket change on the gfs Ford Ka. Simple enough.... But then I tried readjusting the tappet clearences and I think I cocked up a bit as the car now seems to have a misfire. One of the valves needed adjusting quite a bit - so I thought, and by my thinking, Ive adjusted it too much and gone too low and the piston has come up and bent the valve slightly. The engine does sounds sweet as in the bay (well, as sweet as a KA engine can sound), but there is a puup puup puup noise coming from the exhaust. The 'ticketty' tappet sound had disappeared too. The other thing which I noticed was that when you disconnect each HT lead, the engine dies, except the 4th cylinder. By my thinking, there is no compression, because the valve is out of its seat, so the mixture is just seeping out through the exhaust and not causing the engine to stall....? Would the bent exhaust valve be a likely diagnosis for this problem? Quote Link to comment Share on other sites More sharing options...
David Reid Posted March 15, 2010 Share Posted March 15, 2010 IMO it would be impossible to adjust a tappet far enough to enable the valve to contact a piston, i dont think you even have enough adjustment to do it. I suspect you have just done the clearances too tight and when it gets warm its held open slightly hence running on 3 cylinders and no tapping noise. What clearance did you adjust them to? Are you familar with the rule of 9 for adjusting them? Quote Link to comment Share on other sites More sharing options...
jk136 Posted March 15, 2010 Author Share Posted March 15, 2010 Originally no, I didnt do the rule of 9, but adjusted how I thought it shoud be then tried the engine and it was still tappety. So I backed them off a bit and started again using the rule - when number 1 valve is compressed, adjust 8, then 2 and 7, 3 and 6 etc etc. And now it sounds fine - better than ever. Just the puup puup noise from the exhaust now! I think I may have bent no.4 exhaust valve the first time around because it seemed to adjust quite a bit... and I had to back it off alot the second time around... I forget which way round it was but one was 0.2mm and the other was 0.5mm Quote Link to comment Share on other sites More sharing options...
GMan Posted March 15, 2010 Share Posted March 15, 2010 do a compression test on it, if it's bent you will have 0 compression Quote Link to comment Share on other sites More sharing options...
SUPRALOOPY Posted March 15, 2010 Share Posted March 15, 2010 Originally no, I didnt do the rule of 9, but adjusted how I thought it shoud be then tried the engine and it was still tappety. So I backed them off a bit and started again using the rule - when number 1 valve is compressed, adjust 8, then 2 and 7, 3 and 6 etc etc. And now it sounds fine - better than ever. Just the puup puup noise from the exhaust now! I think I may have bent no.4 exhaust valve the first time around because it seemed to adjust quite a bit... and I had to back it off alot the second time around... I forget which way round it was but one was 0.2mm and the other was 0.5mm Thats the rule of nine. Also were those clearances stated on the rocker cover as they do differ. Quote Link to comment Share on other sites More sharing options...
jk136 Posted March 16, 2010 Author Share Posted March 16, 2010 Thats the rule of nine. Also were those clearances stated on the rocker cover as they do differ. Yes they are printed on the rocker cover... Something like 0.2 0.5, 0.2 0.5, 0.5 0.2, 0.5 0.2. Quote Link to comment Share on other sites More sharing options...
shima60 Posted March 16, 2010 Share Posted March 16, 2010 ahhh join the club. i was in a rush one day on the old civic run around forgot the do one of the tappets all together started the engine and BAM loud clank and miss fire the death of the coupe. my own fault for being me really. Quote Link to comment Share on other sites More sharing options...
jk136 Posted March 16, 2010 Author Share Posted March 16, 2010 ahhh join the club. i was in a rush one day on the old civic run around forgot the do one of the tappets all together started the engine and BAM loud clank and miss fire the death of the coupe. my own fault for being me really. Well Ive had another look at it tonight, as one of the guys at work said that sometimes plugs can break down under pressure, so even if it sparks whilst outside, it may not inside. So to illiminate this, I swapped it with another 'working' plug but got the same result. I have also been told to check is the pushrod itself. Normally, the pushrods will bend before the valve does, but I ran out of time tonight to whip the rocker cover off and check. Finally, I removed the offending plug and cranked the car over, obviously alot of pressure and 'some' debris came from in and around the spark plug hole.... but is it me, or should I get a strong odour of petrol or not, or at least a fine mist coming out if the spark plug hole is open? It looked pretty dry in there as i turned it over.... Quote Link to comment Share on other sites More sharing options...
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