Guest Civilizeddog Posted May 21, 2012 Share Posted May 21, 2012 I finished some minor engine maintenance this winter and while putting one of my 93's camshafts back in, there is a SMALL chance that I missed the timing by one tooth. I am certain I was at TDC when I was removing and installing the camshafts and the timing arrows appeared to be spot on. My question is, if I did miss my timing by one tooth, what kind of difference in performance would I notice and how much of a difference in performance could I expect? If anyone reading this has made this folly please chime in. Any and all comments (even flames I guess) are welcome, thanks! Link to comment Share on other sites More sharing options...
Guest Posted May 21, 2012 Share Posted May 21, 2012 Re-check the Cams, You don't want to take the chance of having a valve kiss the Piston! Link to comment Share on other sites More sharing options...
Earthshake Posted May 21, 2012 Share Posted May 21, 2012 I'm not sure how tight the tolerance is on a '93, but I would be concerned about a valve hitting a piston. Link to comment Share on other sites More sharing options...
Member Contributer gll429 Posted May 21, 2012 Member Contributer Share Posted May 21, 2012 oh for gods sake... did you align the timing marks when you took the bike apart? take pix? if not ..do so next time.. did YOU mark the cams, so you have the correct head postion? if not...do so next time. THIS time.. SLOWLYrotate the motor by hand a few times.. and see if all the timing marks line up .. if the motor STOPS dont force it.. back off and recheck that cam. Link to comment Share on other sites More sharing options...
Guest Posted May 22, 2012 Share Posted May 22, 2012 Don't get so stressed out gll, I know its frustrating when other people are not as smart as you, just hang in there buddy and we will get through this. Yes I aligned the timing marks, yes I took pics, no I did not mark them myself since there are great big etched arrows on the gear and since they were aligned when I achieved TDC I figured I didn't need to write on the gear. I did rotate the motor by hand, it turned fine. I've taken her out on the road and I have noticed a loss of the broad power band I had become so accustomed to last summer. I now have to up-shift much faster than before as the RPMs max out very quickly and my top end speed maxes at 90, 95 on a downhill, and maybe 100 after a minute of open throttle and a strong gust of wind pushing me along. This is why I am wondering what one would notice performance wise if timing was off just a tad. Link to comment Share on other sites More sharing options...
Member Contributer gll429 Posted May 22, 2012 Member Contributer Share Posted May 22, 2012 did you remove all 4 cams? misplace them? cam may LOOK the same but wear in differently. why remove them in the 1st place? did you adjust the valves? Link to comment Share on other sites More sharing options...
Guest Posted May 22, 2012 Share Posted May 22, 2012 I wanted to check valve clearances, a few were out of spec. Replaced the shims that needed replacing and proceeded to button her back up. I placed each cam shaft in its own container and labeled each container accordingly. Everything I removed was photographed and put in its own container and labeled. I took notes with every step. I am going to buy a positive stop tool and get back in there to find out what's really going on. I've been reading up on off timing symptoms and it sounds very likely that I may have advanced the timing. Any recommendations on a good positive stop tool or is one pretty much the same as the other? Link to comment Share on other sites More sharing options...
Member Contributer gll429 Posted May 22, 2012 Member Contributer Share Posted May 22, 2012 you already found your problem.. you adjusted the valves.. i am guessing at least 2 are out of spec now.. being too tight... therefore not closing all the way when the bike is warmed up. its possible the crank moved forward or back a tad.. making all the cams line up.. but still be out of sync with the crank.. Link to comment Share on other sites More sharing options...
Guest Posted May 22, 2012 Share Posted May 22, 2012 Why would they be out of spec? I checked them with feeler gauges before and after, they were correct after I was finished. By moving the crank I would probably get a false positive when lining up the timing marks to the cylinder head casting... crap. How to fix, just do it over? Follow up question, how do I keep the crank from moving, is there some way to lock it in place? Link to comment Share on other sites More sharing options...
Member Contributer gll429 Posted May 22, 2012 Member Contributer Share Posted May 22, 2012 yep.. recheck all the marks.. and do over if needed. you say the valves are in spec.. set them with a mid to large gap.. as for the positive stop.. i use a spark plug with everything stripped off and tapped in the middle for a long bolt. its best to have a pal hold the crank in place with a long breaker bar Link to comment Share on other sites More sharing options...
Member Contributer trjerm Posted May 22, 2012 Member Contributer Share Posted May 22, 2012 just redo the one thats out. I just adjusted the valves on my 4th gens and only removed one cam @ a time, changed shims then reinstalled cam and rechecked clearance before moving to next one.I did have to set timing marks approx 1 tooth above level with valve cover,when loose, so that when cam positioning caps were in place and torqued the timing marks would line up. Be sure to turn eng over by hand and recheck timing when done. Link to comment Share on other sites More sharing options...
Member Contributer 5232eagle Posted May 22, 2012 Member Contributer Share Posted May 22, 2012 for what its worth i changed the timeing belt on a honda civic once and i had the cam off one notch ,i could tell the engine had less power and also the coolant temp was much higher. Link to comment Share on other sites More sharing options...
V4 Rosso Posted May 22, 2012 Share Posted May 22, 2012 I've been reading up on off timing symptoms and it sounds very likely that I may have advanced the timing. It sure seems so. And yes, when the cams are not timed properly it has a severe impact on performance. One tooth is not just a tad, it is about 16 crankshaft degrees off. Get in there and recheck/redo the camshaft timing. You don't need a positive stop tool, just follow the Honda service manual procedure, it may take more than one go to get it right. Link to comment Share on other sites More sharing options...
Guest Posted May 22, 2012 Share Posted May 22, 2012 I'll get back in there today and see what's doin'. Thanks for the input everyone! Link to comment Share on other sites More sharing options...
Member Contributer IntAceptor Posted May 22, 2012 Member Contributer Share Posted May 22, 2012 When I do mine, I find an area where there is no tension on the valves from the cam lobes and then using an etching tool, mark the mating teeth in the gears before removing a cam to replace a shim or two. This way, from the get go, don't have to worry about aligning the timing marks up with the engine and I am absolutely sure things are going back in the proper place. During the initial measurements, I do line up the proper marks to check for the right gap. Link to comment Share on other sites More sharing options...
Guest Posted May 22, 2012 Share Posted May 22, 2012 Trjerm, your a genius man! I think that's EXACTLY what I did damn it... When I took the camshaft holders off they DID move up just slightly but yes, the timing arrow did move up a degree and I DID NOT compensate for that when reinstalling them. I'm glad you said that. I know exactly where to look today when I get back in there. I can't believe I didn't think of that. Link to comment Share on other sites More sharing options...
Guest Posted May 22, 2012 Share Posted May 22, 2012 IntAceptor, that is also a good idea, that way you know you won't be getting any interference from the valve bucket pushing up on the lobes and you know your mark is true. Thanks for that gem, I'll use it. Link to comment Share on other sites More sharing options...
Member Contributer trjerm Posted May 22, 2012 Member Contributer Share Posted May 22, 2012 make sure you bring the caps down in steps using the tighting sequence shown in the manual, the caps are very pron to cracking if youn just crank them down. Link to comment Share on other sites More sharing options...
Guest Posted May 22, 2012 Share Posted May 22, 2012 Oh believe me, the common service manual has been my bible for the past 3 months. Link to comment Share on other sites More sharing options...
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