Timing Help Please

[aaronscomp]

Ok so i just put my motor back together after i bought and foudn out the idiot droped a screw in cylynder 1. So i ripped the motor apart to get it out and change the head gasket. I put everything back together and it just pops and sometimes starts and runs like crap for like 20sec. Im beggining to belieave im a tooth off on the exhaust side heres a pic let me no what you think. Thanks

[silvia s14.5 rb25det]

take some time. heres what you need to do. (master techs correct me if i'm wrong) take the upper cover back off carefully. scrape off the silicon off the head and the cover.take your spark plugs out so you can rotate the crank easier.after that set #1 piston at TDC. stick a long rod haha down in the cylinder to help indicate TDC.the little pin on the lower cover should be very close to lining up with the second mark on the crank pulley when you get to TDC on piston #1.take the top cam chain guide off.take the cam chain tensioner off. be careful not to drop anything down into the lower cover or you will be pulling that s**t off too and resiliconing stuff sucks A**take off the cam sprockets and chain.line the two dark chain links with the two dots on each sprocket and just hold them in place with your fingers and set it on a table.since your motor is at TDC on cylinder #1, the notches where the sprockets fit on the cams should be in the right spot to when you put the sprockets on the dots on the sprockets should be like if the two dots were sitting on the top of the letter V. you can also refer to a manual that shows the position of the cam sprockets when it's at TDC on cylinder #1.pick up the cam sprocket with the chain sitting on the right teeth. timing marks.you might have to take one cam out and then put it back in to get the yellow link on the idler sprocket. after that, kinda hold the sprockets to the notches in the cam with the cam bolts in about 2 threads. the cams wont slide on yet.get someone to turn each cam (start with intake) so the sprockets slide on in that "V" position from earlier. you should not have to turn the cam much AT ALL to make them fit onhand tighten each sprocket bolt after you slide each sprocketrepeat for exhaust. torque cam bolts to hang on the bolt 60ft/lbsput tensioner back on with a pin or something stuck in it to hold it back. turn the crank so the slack on the cam chain is on the left side of the assembly, hold the slack there and pull the pin out.

you have timed your motor correctly my friend. you will notice that if you turn the crank a few times it will seem like the dark chain links and the dots on the cam sprockets wont line up anymore. this is because of the odd number of chain links on the tensioner side. this also insures that the chain and sprockets wear evenly. however the timing marks at TDC on piston #1 on the crank pulley, the idler sprocket and the cam sprockets will align to indicate TDC on piston #1

if i remember correctly all of this should be correct.

do research


Modified by silvia s14.5 rb25det at 11:22 PM 6/26/2009

[liquid_cool]

take a pick of your cams position from the top please..so we can see the lobes position of the #1 cylinder.

there is an easyer way to time allso...its called timing marks on your crank dampner....if you keep your engine clean..you can see them..to find TDC..top dead center..

#1.) remove spark plug from #1 cylinder#2.) Place plastic bag down the hole (not all the way in obviously)#3.) bump engine over..not crank..till bag goes flying out..with a pop sound.

now look at that crank..you should be somewhere close to top dead center on the compretion stroke...use a socket and long rachet on the crank to adjust the position of the marks from there...now look at your lobes on your cams...the #1 lobes should be pointing away from eachother but still slightly upwards pointing...like exahust should be inbetween 2: and 3:00..and intake inbetween 9:and 10:ockl....the actual timing marks that drive everyone crazy..dont really matter..as long as you are in the compretion stroke of the #1 cylinder..you can then set up the timing ..its simple.

[DjPantsSpecR]

I didnt read these two gentlemans posts, as im busy and at work, i apologize if they already answered you.

You are one tooth off on the exhaust cam. Rotate it one tooth CW.

However, in your haste there is no guarantee that that is the only problem, you may have lined up the idler sprocket to the lower chain wrong (37 teeth and 18 teeth means you8 can be half a tooth, or 9 degrees off.) The car will still run, it will just be down on power, you may not even notice.

But for now FOR SURE, pull the number one spark plug out, put a long extension into the spark plug hole, and crank the motor a little forward and a little back to MAKE SURE you're at TDC on number one.

If you are, pull the exhaust cam, rotate it one tooth cw, button it up, AND CHECK YOUR DISTRIBUTOR.

It should be pointing at the number one wire. Get a timing light out, and see if it fires up. This is teh EASIEST way to see if youre half a tooth off. You wont be able to set base timing at 20 degrees without having to rotate the distributor a ridiculous amount.

But if you dont do anything else, rotate that cam before you start bending valves. However, if you dont check for TDC too, you WILL bend valves.

EDIT: i wrote ccw a bunch when i meant cw, that was a close one. The best cam alignment guide is from JWT, even the fsm is crap.
Modified by DjPantsSpecR at 10:07 AM 6/27/2009

[aaronscomp]

I pretty much did all that i set it TDC for 1-4 i checked with a flashlight. I then went over to my other de in the gurage set it to TDC. I was off a tooth on the intake side too. After gettting the cams right it still does the same thing. Ive got it to run just very crappy and dies out eventually. I put everything TDC and nothing at all if i switch plug wire 2 and 3 around it will pop but wont fire up.