sr timing issues

[420sx]

serious sr timing issues.
ok let me write a little short fucking sad story.

anyway, im doing a rebuild for extra cash so i can score a cage.

the car s13 coupe with sr. redtop.

replaced the headgasket. everything going gravy. put the motor in, pluged in etc. its all good till.....



try to crank - the motor wont build compression. just wont. turns over compression test shows below 20. wtf.... ok, i tripple check the cams:

TDC..... 10 intake 12 exhaust. 20 links in between on top. lobes facing 9 and 3 respectifully. chain is on tight, everything is gravy. cas is stabed in right.....

try to Leak down test...... nothing. no bubbles. i thought MAYBE i fucked up following FSM on headgasket.... did what it said torque all to 28, them 53 then loosen and torque to 32. done. wtf.... no air bubbles in leak down everything is fine.

i find the intake compression stoke. set to tdc again. alight the cams. set the chain. everything fsm spec.

nothing... fucking torque a lil more.

what the fuck guys
im super frustrated.




chime in, im almost out of ideas.:rant:

[bardabe]

Did you put the piston rings int he right order and gap? that makes a big ass diference. I know from experience. if not Valves are leaking, headgasket is torqued to spec and its not building compression. I can almost be sure its the Pison Rings.

[slider2828]

Well you sure counting 20 links will work? The chains should be tight on both sides down to the block, but between the cams, there is actually a little slack. Match up the timing marks is the most accurate and you can search on this forum to find the right pictures.

How did you do the compression test? 3 Plugs in and 1 plug out where the tube goes. Keep the throttle open and make sure there are 4 full cranks and then read the numbers.

Good luck let see what you come back with

[statik]

could you have switched the cams? honestly im not sure if that can cause this, but if the leak down is good at TDC on each cylinder then it sounds like the rings/valves/hg are fine, only thing I can think is the valve opening/closing is wrong so you can't build compression

[420sx]

im going to retourque the head and reinstall the cams. ill come back when its done tonight

[-=RS13=-]

i thought MAYBE i fucked up following FSM on headgasket.... did what it said torque all to 28, them 53 then loosen and torque to 32. done.


This is done wrong.

Final torque is definatly not 32 Ft/lbs

Arp's are torqued to 80 Ft/lbs, stock i think is 32, then turn the each bolt 90 degree's.

[statik]

This is done wrong.

Final torque is definatly not 32 Ft/lbs

Arp's are torqued to 80 Ft/lbs, stock i think is 32, then turn the each bolt 90 degree's.

thats assuming hes using Arp's, which he never said

[420sx]

yes. i called arp they told me to torque like stock(!!wtf). i searched quick found it was 80lbs

[slider2828]

he is right though, regardless of arp, the last torquing sequence is two 90 degree torques in sequence for sure!

[statik]

yes. i called arp they told me to torque like stock(!!wtf). i searched quick found it was 80lbs

oh boy, did you not get the little piece of paper inside the box? =]

[420sx]

no he had arp studs and cometic.
he overheated - he ran a temp gauge BEFORE the oem thermostat and also ran a fan thermo switch that plugs in inlet pipe and blocks 70% of flow. but thats "fine" by him. cause hes an expert.

they are torqued to eom spec right now and it WILL NOT build compression. oh boy... im gonna take off the cams again and torque in steps to 80lbs.
i hope that solves the problem.... but im sceptical already, i never had such a hard time with a head before

[slider2828]

Damn either he didn't torque it right or he did overheat. But whatever HE did, he screwed up with blocking the fan and running the temp gauge at the wrong spot.

[-=RS13=-]

thats assuming hes using Arp's, which he never said

Even if he was using stock bolts its still wrong.

32 ft-lbs???

Looks like you missed the other half. SR FSM

http://img180.imageshack.us/img180/5278/hemg2.png (http://imageshack.us)

But arp's go 30 ft-lbs -65 ft-lbs -80 ft/lbs

[bshotts]

Glad somebody caught the last step he did...always helps to read the whole procedure through. Wish you luck with this 420...keep us updated!

[420sx]

yea i did the 90s. but i have to redo it tonight since arp torque spec is different. wtf that rep told me it was oem. ass

[420sx]

im gonna retorque the arp's and set the camps etc. if if dont get compression then im out of ideas. wtf.

[zoototheyork]

you are 180 degrees off?

[zoototheyork]

you are 180 degrees off?

[420sx]

UPDATE.

dead a leak down test.


RINGS ARE SHOT.... i told the dude its cheaper to buy another motor.
builds compression only with oil. temporarily seats the rings but goes away very quick. ;(

morale of the story:
kids, before u pull the motor for a headgasket swap do a leakdown test thorowly