2.6 Astron EFI lost compression in all 4 cyl

[damian]

need help please

just "stalled" while driving home and won't restart
turns over fine

valves move so timing chain ok.
all plugs ok, no oil water or fuel on em.
has spark.
has fuel.
has no compression on ALL 4 cylinders (only checked with the old stick a finger in test)
not blowing air into radiator.
no hole in the block where a piston has tried to escape.

I'm lost?

help please - ideas?

[geezer101]

What condition is the timing chain? Is the timing still in sync? Pull the rocker cover off and bring the crank pulley to TDC- take a look at what the cam's doing. It would take a monumental blow out to rob all cylinders of compression.

[mstrrab1992]

wow....lost compression in all 4? cant be 4 bung rings, LOL, did u hear a boom? crank may have snapped at the front??? for it to have NO compression.....Is there a massive hole in the side of the block?? Lol.. for it to have no compression =\ thats a doozey.

[Billsy]

sounds like the chains skipped and youve got bent valves

[A112H]

+1 for chain skipping a beat or 3. If the tentioner gives up and the chain gets super slack that will do it. Pull the rocker cover and I bet the chain will be loose, still connected but loose.

[damian]

thanks for the advice guys

yeah she just died (appeared to stall) last night as I pulled into my brothers driveway.
I've got a feeling it's timing chain skipped a couple teeth, and the more i think about it, the more it does sound like a tensioner loose in there - that would explain the noisy motor since Sunday night.

These motors are non-interferrance i presume? or not, as Billsy seems to imply (bent valves)?

I will take the rocker cover off this weekend and have a looksee

[mstrrab1992]

if it has no balance shafts its quite common for them to skip a few teath.

[damian]

i haven't done any mods to the motor, so i presume it still has the balance shafts in

[damian]

ok, rocker cover off, timing chain looks perfect.
little bit of slack, but nowhere near enough to be able to skip teeth.

with No1 at TDC, rotor is pointing towards no2 cylinder - this is normal?
i sorta thought at TDC, rotor would point towards no1 ??

after chatting to superscan, think it's prob blown the HG between cylinders, hence no compression, but also why no oil in water or vice versa.
should really go buy a comp tester...

will rip off head next weekend and looksee and report back

[mstrrab1992]

if theres water in ur oil, ur cylinder bores may be full of oil and water from a blown headgasket?

[geezer101]

This should help you on your way (with a bit of luck)
http://www.sigma-galant.com/viewtopic.p ... .6L#p49864

[damian]

Mr stab reread my post above
mate. no water and oil mixing.

geezer cheers buddy. hmmm, so it appears my timing IS out by 90 deg.

ok, but chain seems fine? will just have to pull the head off and look

tried turning it over before taking rocker cover off
it sounds like it almost wants to start
and it was kicking smoke out the intake inlet?
didn't smell electrical, smelt like, well, a car. exhaust to be precise.

thinking about it, chain must have slipped
how else can timing be out 90
and it explains the sudden (apparent) loss of compression

so compression test
then remove head and report back

[damian]

whoops double post

[mstrrab1992]

i take back what i said, i didnt read it properly, my apology, i didnt see "No oil in water or ..... "

[damian]

nah that's cool buddy, need all the advice I can
Benno is the mechanic, wanted to nut it out before he gets back from os

ha! he's back today, but gotta give him a week off.

next event is November 6 motorkhana
then state titles khanacross on 19th Nov
but should have the stigma of love back up and running for the 19th

[81GL]

Timing is out eh? talented.

Has the distributor got a metal gear on the end or a nylon one? I've seen a few nylon ones wear out before.

[damian]

metal.
drives on dizzy look fine, not worn or loose

compression test
inspect dizzy
head off
see what we find

[A112H]

I think I would pull the front cover off before the head. If the tensioner has gone and there is no mechanical damage to the valves, head, pistons or block you might get away with a new tensioner and re setting the cam timing.

[C_Fernance]

What about the rotor button inside the dizzy? They are located on the shaft with a plastic key and i've managed to sheer off 2 of them (1 in a magna efi dizzy, the other a GH Sigma).

With the sigma the battery had come loose and I didn't know. Was driving great till I went to take off quickly at a set of lights. Took off OK, then started missing, backfiring and so on. Stalled as soon as i put my foot on the clutch. Tried restarting and it would turn over but not fire. Turns out the battery had hit the cap, sheered the rotor key, and then moved back to the tray as I pulled over. Was a bit of head scratching on the side of the road wondering what was wrong till i noticed the cap wasn't sitting on 100% right.

[mstrrab1992]

What about the rotor button inside the dizzy? They are located on the shaft with a plastic key and i've managed to sheer off 2 of them (1 in a magna efi dizzy, the other a GH Sigma).

With the sigma the battery had come loose and I didn't know. Was driving great till I went to take off quickly at a set of lights. Took off OK, then started missing, backfiring and so on. Stalled as soon as i put my foot on the clutch. Tried restarting and it would turn over but not fire. Turns out the battery had hit the cap, sheered the rotor key, and then moved back to the tray as I pulled over. Was a bit of head scratching on the side of the road wondering what was wrong till i noticed the cap wasn't sitting on 100% right.

read

metal.
drives on dizzy look fine, not worn or loose

compression test
inspect dizzy
head off
see what we find

[geezer101]

He didn't mention the rotor button. And a stuffed rotor will definately not cause complete compression loss. Money's on timing chain jump. Had a timing belt strip a few teeth once but first looking at it, it appeared it should run(got the spark, injectors cycling, engine turning over...) Checked the cam location and bingo.

[mstrrab1992]

ohhhh, right. my bad. thank you geezer

[damian]

thanks all, will report back when we've pulled it apart.

plan is:
compression test (and maybe leak down test too)
pull dizzy off and inspect
pull front timing cover off and inspect
pull head off and inspect

[rx22nv]

Hold up, when the pulley mark is at TDC, and the cam dowel is at the lowest position, it just means you are on the wrong stroke. Rotate the engine one more time and then you should have the pulley on TDC, the cam dowel pin at the 12 o'clock position and then You should check the timing and also check the dizzy.

I seriously doubt the chain would slip a half revoution exactly.

Check your valve clearances, maye sure they aren't too tight. Too tight means valves open and no compression. Do this when the motor is at TDC.

[damian]

cheers rx22nv.

got my cuz is a qualified mechanic to look at it with me.
timing chain giude or tensioner has let go, chain is loose as.
definately slipped.
when motor is at tdc, the rotor button is pointing to no 2 lead

dizzy in perfect nick

zero compression in all 4 checked with compression tester.

car sent to the wreckers after stripping all the good stuff, and offering/giving away panels and left over parts on magna forums.
it served its purpose - a cheap bit of fun until the Stigma gets back on the track.
Paid $200 for it - wreckers picked it up and gave me $130, got $40 back on rego, $80 for various parts.
Sweet

time to concentrate on the Stigma again

Cheers to all for your help and tips, sorry I couldn't give closure with pics of what went wrong.

...Money's on timing chain jump...

someone pay the man

[geezer101]

What? I got it right!!?! Cash only thanks...

[A112H]

+1 for chain skipping a beat or 3. If the tentioner gives up and the chain gets super slack that will do it. Pull the rocker cover and I bet the chain will be loose, still connected but loose.

[damian]

whoops, you two can split the cash ;)

[Billsy]

I want my cut too :p

Not the best outcome. But realistically after what happened. The obvious answer
If you need a née head I've got a couple to pick from.

[A112H]

whoops, you two can split the cash ;)

LOL