Thread: installing cams and TDC....

so during my cam install, while trying to get the motor set at TDC while looking on the crank pulley and truning it over .. there are no visible timing marks on the pulley....

wen the cam gears at 10 n 12 and the motor is TDC( i think )there is an easy spot when turing the crank pulley which makes me think its at TDC....Which way will the cam lobes be pointing?

i do have 20 links in btween the 10 n 12 mark

how else can i tell if im set the right way to takout/install hte cams?

The cam lobes on both cams will be pointing away from each other when it's at TDC. Not exactly 180 degrees but 'generally' away from each other. Easiest way is to verify TDC is to pull the no 1 spark plug out. It's the one closest to the pulley side.

Stick a long screw driver in there and turn the crank pulley over until the piston is at it's highest point. That's TDC for the motor.

Oh and on the cam chain, there should be 9 complete outside links between the two markings on the cam sprockets. Or 11 including the two links that go over the teeth with the markings on the sprockets. Check the JWT website. They have a nice write up with pictures, so you are sure your cam timing is correct.

(ps: I'd look for another crank pulley with the right markings or at least reference one and make the necessary marks on yours)

thats not entirely 100% true or for that matter accurate.

theres a certain point of dwell time, when the piston is neither travelling up or down, which will last a few degrees of movement either way, the centre of that dwell time, is true tdc, the only way to find it is to use a dti and a degree wheel.

so heres some pics.......
[img][IMG]http://i149.photobucket.com/albums/s71/ordepg/IMG_1243.jpg[/img][/IMG]
[img][IMG]http://i149.photobucket.com/albums/s71/ordepg/IMG_1244.jpg[/img][/IMG]
[img][IMG]http://i149.photobucket.com/albums/s71/ordepg/IMG_1245.jpg[/img][/IMG]


so heres the before and after....do the lobes look the same? i sur hope they do to me....this is my first n only time installing cams

[img][IMG]http://i149.photobucket.com/albums/s71/ordepg/IMG_1246.jpg[/img][/IMG]
[img][IMG]http://i149.photobucket.com/albums/s71/ordepg/IMG_1247.jpg[/img][/IMG]

Make sure that you put lubrication on all the wear surfaces before you bolt it together. I don't see any in the picture.

I think this is one of the worst ways to do a cam change.

Always do one cam at a time. This means never take off both cam bearing cams at the same time.

This method above is the way JWT has it on their site. This method has caused many a problem for people.

There is a much easier way to do cams that is way more fool proof than this.

I hope all goes well with your install.

yeah if its just changing out cams i do one at a time and dont even bother taking off the gear while the cams are still in postiion. What ill do is before i even remove the tensioner ill loosen the bolts for the cam gears just so i can easily get them off to switch them over. Then remove the tensioner after lining back up to tdc. Ill start with the exhaust cam first, Mark the chain where the dot is which really isnt totally necesary cuz you can always go by where the other cam dot is and count 20 pins over.

Then put the gear on the new cam, set it into postion and tighten it down. Then move to the intake cam and do the same. You will always be keeping good tension on the chain if you do it this way and you are very very unlikely to skip a tooth on the crank. Skipped teeth usually occur when you have both cams out at the same time. So far its worked with no isssues and i have removed and installed cams more times than i can even account for.

True, but I am hoping the guy will be able to see where the old markings are if he is fairly close (within a cm or so on the crank pulley) to tdc in the first place. I really doubt he has a degree wheel considering he posted this up.

Pedro you should get the markings on the pulley fixed cause how will you def need it to get your timing right as well.

I did my cam install with the JWT guide using the triangular wood piece and I haven't had any problems since the install. I didn't even touch the tensioner.



^I argee. This is a must. Get those bad boys lubed up. Then follow the break in period. If you are running on the stock ECU, they will have to learn the cams. You will loose low end as well, but they come alive around 5K after the break in period.

ya i hope it goes right for me too....ya this was following the jwt site how to....



i did switch them one at a time. cuz i thought i would **** it up alltogether, until i put the wood block in the chain and i tried to move the chain around and it didnt....i tried to do them with the tensioner stillin nu it woudnt let me so i took it out for the time being....i dont think i had both cams out at the same time, but i did have both gears off at the same...i have before pics like wat i posted above so i can get them back as close as possible...



ya i think im victim of the oem crank pulley seperation on my sr...setting the timint was a bitch..



yaeh i used the wooden block as well. i made 100% sure that it wouldnt let the chain move ata all..but i had to take out the chain tensioner cuz there wasnt enought slack.....


well im gonna finish up this install..and lube it all up. any last tips? i hope all goes well before i start er up........:o