issues after rebuild.

[huntington19]

I rebuilt my ka in july and it hadn't started since this past thurs when redid the connection wires to the fuel pump. I did a compression test and it said 150 across all 4 cylinderes. at TDC my cams are lined up. however...the marks on the gears don't line up.. so i just lined them up by the lobes. redid the distributor timing 4 times and i got it to run but very poorly. it shut off after a few seconds. it sounds like a timing issue.. but i've run out of ideas..

also..i have s13 cams in my s14 ka.. i heard that the color striping is flipped between s13 and s14....

s14: green=exhaust; orange= Intake
s13: green= intake; orange= exhaust

is that right?? if so.. if my cams are flipped could bad valve timing be the cause for low compression??

AND one last question... is there a difference in thickness between s13 head gaskets and s14 ones?

help help help!!!!!

[SoguRacing]

sounds like you need to do more research on your own. It more than likely is valve timing. Even being off a few degrees will make your engine run horrible if the valve timing is off. recheck them again and do some more research.

[huntington19]

yeah. i definitely need more info. i'm just praying that valves aren't hitting pistons in the mean time. thanks for the advice.

[ManoNegra]

low compression could be the cams overlap is wrong
you need 4 extra roller links to bring your timing within 3°
front cam lobes need to be flat and pointing away from each other at TDC
been a while since we've done this so I can't remember the right color of intake/exhaust cams
(we usually measure the lobes to make sure - pita but safer)

then here's also always the chance that you put things together wrong and bent a valve...


edit:
are you doing two s13 exhaust cams or just regular cams?
the 4 extra roller links bit is to bring two s13 exhaust cams in line
disregard that if you're putting in a stock setup

[let5l1de]

Be sure you inserted the s13 cams in the green = intake and orange = exhaust configuration.

double and triple check all your timing components.

Did you rebuild the head? If you did, you must check the shim/bucket to cam clearance. The clearance should between .013" - .016" for intake and exhaust.

If you are unsure of bent valves, use clean compressed air with a line (and gauge) screwed into the spark plug hole. The piston should also be in the bottom of it stroke with the valves and or cams in the closed position.

~m

[huntington19]

thanks for the help guy. turns out i had the cams installed flipped. my mistake. but after i reinstalled them the correct way and messed with the distributor timing she fired right up. now the only issue is really rough idle. could it be caused by my o2 sensor closest to the block being fried or the egr valve being closed off.

that's my issue at this point. lol any advice on that??

[ManoNegra]

timing could still be off.... or bent valves.

[huntington19]

if it were bent valves wouldn't you hear noise coming from the head??

[let5l1de]

Only when the valve(s) and piston(s) had smashed (like this:snoop::boink::mephfawk::wtc:) for the first and last time...

Perform a leak down test an all cylinders. You may also measure the lash between the cam and shim. If tolerances are over .016" on any valve or all for that matter, most likely the valve head is not allowing the valve stem to fully seat back into position (install height) creating larger tolerances...

Tell us what you find.

~m

[huntington19]

oooookay so after rewiring up to the harness and installing my new o2 sensor. i fired her up and the idle is still a little rough. mind you i plugged all the left over egr and evap lines that had somewhere along the line been forgotten about. the idle is a little below 1000 rpm. and it shudders. but after thinking about it my guess is that it's because of the cams. they're more aggressive than stock s14 cams and there could be some valve overlap. however...it's drivable.. and i can finally take her home :) thanks for all the advice. if you've got anymore about the cam and valve overlap thought let me know. :)