sentra Posted September 29, 2008 Share Posted September 29, 2008 chasing a tick, having only ever played with piston engines with hyd lifters, some homo put solid lifters in mazda b6t and to adjust you ahve to remove t/belt, camshaft, so before i bothered going through that rigmorole i thought id ask if anyone thought there numbers were particularly bad. cam over valve stem stz inlt: (0.25,0.25)(0.38,0.38)(0.20,0.20)(0.23,0.20) exh: (0.23,0.23)(0.25,0.30)(0.28,0.15)(0.25,0.20) from what i gather from other motors of the same style but with factory solid lifters the clearance should be ~ in .15 ex .30? chur Quote Link to comment Share on other sites More sharing options...
Unclejake Posted September 29, 2008 Share Posted September 29, 2008 ^ I assume this is a four valve, twin cam and the readings were taken cold? I also am assuming that the valve stems use buckets and shims..... If neither of the above are true then I don't understand your readings and you should completely ignore me. #2 inlet is most likely the ticking culprit but it is very strange that both valves are so far out but out by an even amount. Does this engine have an oil spray bar onto the camshafts and if so how does the camshaft look on #2 inlet? Quote Link to comment Share on other sites More sharing options...
sentra Posted September 29, 2008 Author Share Posted September 29, 2008 wherei was going was "do those numbers = certainly noisy or a bit of a meh yeah mabey?" yeah 4 valve twin cam, i just went and quadtripple checked it and those numbers are correct, everything looks a+ condiation, cam looks just run in (aftermarket) & lobes measures up same as others, lifters have perfect running pattern it comes factory with hla's and someone has put in a solid cam & lifters (cant figure out how it is oiled i should just take it apart and out hla's back in it but am waiting on a post hoist before i can be fucked working on a gaybo east west motor Quote Link to comment Share on other sites More sharing options...
kpr Posted September 29, 2008 Share Posted September 29, 2008 yup the two .38's on the inlet. probably best to change that .15 on the exhaust as well. .25 in .30ex is what kelfords recomened on my cams (4age) but they are tighter than that factory for memory Quote Link to comment Share on other sites More sharing options...
Unclejake Posted October 2, 2008 Share Posted October 2, 2008 Sentra (cunt) . I am curious about your tick and why you would want to rip the head and sump off right now. Have you eliminated the valve clearance thoughts? I shall assume you have. Does it go away at higher revs? If so I would head toward a single worn gudgeon. Is it always there? If so I think you are looking in the right place (the valve train) or if 'tick' isn't exactly the right word I would consider a too great bore to piston clearance and resulting piston slap. It is of course remotely possible that the previous engine builder neglected to put all the pistons in facing the correct way - but I have never personally heard the noise such an error would create. I also assume you have felt the oil (off the dipstick) and it still has a sliding cushion feel between the finger tips. I have seen and been impressed by your drunken welding skills so please forgive me if I am teaching you to 'suck eggs': An old and very useful diagnostic tool is a long screwdriver or super long socket extension bar. Place one end of the bar against your ear and the other on the engine and you will locate the source of the noise within 100mm at the top of the motor and a bit less acuratley at the middle/bottom of the motor. Once you have that information you can act in a more focused manner that is likely to save money and time. If this was an imperial engine with pushrods it would already be awesome but sometimes a man has to work with what he has got. May the Gods be with you and your rotary. (regards to MMM and please forward any nude photos you have of Pies to vvega) Quote Link to comment Share on other sites More sharing options...
Guest vvega Posted October 2, 2008 Share Posted October 2, 2008 sometimes you can never take away the burning from things you have seen nekid pies bic's would be one of them u/j is on the money + could be a pinhole leak in the ex/ headers / flange / gasket they can also make a tick tic noise Or someones just hooked a dirty great relay to your points just to piss you off Quote Link to comment Share on other sites More sharing options...
Raizer Posted October 2, 2008 Share Posted October 2, 2008 Or someones just hooked a dirty great relay to your points just to piss you off Thanks for the idea! Quote Link to comment Share on other sites More sharing options...
KKtrips Posted October 2, 2008 Share Posted October 2, 2008 does it change with tempreture? Quote Link to comment Share on other sites More sharing options...
peteretep Posted October 2, 2008 Share Posted October 2, 2008 when i heard it, the noise was always there, cold and hot, and it followed the revs, but not really getting any noticably louder(ie not becoming a tick to a smash), but imo its definately a 'tick' rather than a slap Quote Link to comment Share on other sites More sharing options...
sentra Posted October 4, 2008 Author Share Posted October 4, 2008 yeah twas a multitude of valvetrain things-> cam base circle is 4mm down from stock to get the grind they wanted on it to make this work, the valves & seats have been cut & the stems not ground turns out the lifters were hydraulic & have been ground so they run at full extension when riding on the base cicle ala what you do with adjusting screw on a race motor with hlas ? which is fine, but they have gone though the hardning on the lifter (on the valve side) which has subesequently worn into clearance hence tick. (new stem height means lifter is out of range on a stock cam & holds a few valves open slightly) which is fine & now i have a few repair options id like opinions on. (any solid lifters are aftermaket & big $) the best in my opinion-> run ground cam, dissassemble hlas, plug oil hole, replace plunger with appropriate length of toolsteel & grind to get correct valve clearance. #2: get an factory cam ground down to suit the new stem height. (ie just grind base circle & end up with extra lift) #3: grind lifters ala how they have done it #4: remove head, get valve stems ground to factory, put it back togther with a factory cam. etc etc blah blah blah 1 Quote Link to comment Share on other sites More sharing options...
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