cam timing help please 02' 426


4 replies to this topic
  • 7808

Posted May 31, 2011 - 07:58 AM

#1

i just installed a hot cams stage one exhaust cam with auto decomp but im having a hell of a time getting everything TDC lined up, is there no way to lock the cams? i downloaded a manual but it seems kind of vague on the cam installation part, pretty much says 'install cams, then install cam chain, make sure timing is correct of not adjust".. the manual also says "install chain on cams and install cams in trays.." i never removed the intake cam though, i was able to get the chain on/off just by having the exhaust cam half out, but even with the tensioner out its still pretty hard to line up the cams, looks like intake is sevral teeth advanced and the exhaust a few less but still advanced in reference to crank

also i never disconnected the decomp lever cable or removed it, with a auto decomp cam do you still leave that hooked up?

  • Yamaryder29

Posted May 31, 2011 - 08:39 AM

#2

take the tensioner out, line up the mark on the flywheel. It should be the "I". then install the exhaust cam with the 2 dots at 9 and 12 o'clock and no slack on the front side of the chain (opposite the tensioner side). Next, install the intake cam with the two dots at 12 and 3 o'clock(if there are 3 dots install them at 9,12,and 3 o'clock. After this is done, install the cam caps and then the tensioner. Double check all marks, then turn the motor over a couple times, then tripple check the marks once more to be sure they are still lined up. If they are, you should be good to go.

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  • grayracer513

Posted May 31, 2011 - 08:50 AM

#3

Easy things first: The decomp lever is inconsequential once you install the auto decomp cam. You can leave the whole thing, remove the whole thing, or take the cable and lever off, leaving the shaft to fill the hole. If you do the latter, BE SURE to leave the return spring on the shaft lever.

Timing the cams with just the exhaust out can be a bit annoying. It's always seemed easiest to me to time the exhaust first, then position the chain on the intake sprocket based on the number of pins between the cam 12:00 marks, and set the intake in place. Always roll the crank and both cams backward 5 degrees or so, then turn the crank forward to TDC again and check the timing using the marks at 9:00 and 3:00. the 12:00 marks are only an assembly reference, and not to be used for timing per se.

  • 7808

Posted May 31, 2011 - 09:19 AM

#4

thanks guys, im gona try again when i get home today

  • 7808

Posted June 01, 2011 - 03:38 PM

#5

take the tensioner out, line up the mark on the flywheel. It should be the "I". then install the exhaust cam with the 2 dots at 9 and 12 o'clock and no slack on the front side of the chain (opposite the tensioner side). Next, install the intake cam with the two dots at 12 and 3 o'clock(if there are 3 dots install them at 9,12,and 3 o'clock. After this is done, install the cam caps and then the tensioner. Double check all marks, then turn the motor over a couple times, then tripple check the marks once more to be sure they are still lined up. If they are, you should be good to go.


worked good got it done and it starts WAY easier:thumbsup:





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