question on p79 head.
#26
just out of curiosity... that 11:25... is that from the front of the engine or from the drivers side? because i put it in from the drivers side when the engine was out of the car. i may need to drain the oil and re-install the oil pump. unless i can adjust the distributor shaft from the distributor side....?
#27
no need to drain the oil, just pop out the pump and try re aligning the dizzy shaft as per the manual. i had to take out my sway bar for some reason, just the frame mounts to squeak the pump out. dunno if thats common
#28
Yeah, gotta drop the sway bar from it's frame mounts (don't disconnect the control arm links).
A good read about setting the timing on rebuild: https://www.zdriver.com/forums/280zx...embling-26217/
A good read about setting the timing on rebuild: https://www.zdriver.com/forums/280zx...embling-26217/
#29
ok, found the problem. turns out the PO messed up HIS install of the distributor shaft and just moved the spark plug wires around to compensate. we didnt know and left the wires on the cap while rebuilding. my timing is fine. we had to move the wires. now it starts, and runs!
next thing... we need to rewire the car. we have a mystery short. anyone know of a good how-to? is it possible to rewire all the accessories without messing with the EFI?
next thing... we need to rewire the car. we have a mystery short. anyone know of a good how-to? is it possible to rewire all the accessories without messing with the EFI?
#30
The EFI harness is pretty much separated from the rest of the car harness.
As for fixing a short, give more detail on the problem... Tracing a short is a whole lot easier than custom making a 500 wire bundle harness.
As for fixing a short, give more detail on the problem... Tracing a short is a whole lot easier than custom making a 500 wire bundle harness.
#31
okay, but this could take a moment... i will explain the series of events.
before we took the engine out and rebuilt it, the starter would go click but not turn over. (this is with a jump pack installed)
while waiting for the engine parts to get back from the machine shop, i took the dashboard out in an attempt to make a fiberglass one, as mine is cracked like crazy. i currently have the "other" wiring harness just kinda hanging out in the passenger footwell.
installed the engine-
cranked it over, numerous times without a problem, started it up, adjusted the timing and turned it off in anticipation of taking her for the first ride.
its dark now, and i have to install the steering wheel, and i wanted a tach, headlamps, and oil pressure guage. so we grabbed the guages, hooked up the tach, installed the wheel, and flipped the headlamp switch. no headlamps. checked the fuse box, and 1 15 amp, and one 20 amp fuse were blown. the far right fusible link (when standing at the side of the car) was blown as well.
replaced all the fuses/fusible links.
now- when i put the key in, here is the series of events that happens.
turn key to acc, fuel pump primes.
turn key to start, fuel pump turns on, (sounds the same as when it is priming) which stops once i release the key.
once i release the key, the auxilliary cooling fan (injector cooler) turns on, and stays on until we remove the previously burned fusible link or remove the key.
just to be clear, we had no problems until plugging in the tachometer/oil guage (and a few other things that might be incorrect, but still matched the connector. particularly; one 3 prong T-Shaped connector under the steering wheel, and the long 2-row connection at the center of the back of the speedo cluster.
everything is now disconnected, fuses and fusible links replaced, problem persists. electrical gremlins make me want to crush the car with my bear hands.
P.s. i meant bear. not bare. if i had bear hands i would crush this thing.
before we took the engine out and rebuilt it, the starter would go click but not turn over. (this is with a jump pack installed)
while waiting for the engine parts to get back from the machine shop, i took the dashboard out in an attempt to make a fiberglass one, as mine is cracked like crazy. i currently have the "other" wiring harness just kinda hanging out in the passenger footwell.
installed the engine-
cranked it over, numerous times without a problem, started it up, adjusted the timing and turned it off in anticipation of taking her for the first ride.
its dark now, and i have to install the steering wheel, and i wanted a tach, headlamps, and oil pressure guage. so we grabbed the guages, hooked up the tach, installed the wheel, and flipped the headlamp switch. no headlamps. checked the fuse box, and 1 15 amp, and one 20 amp fuse were blown. the far right fusible link (when standing at the side of the car) was blown as well.
replaced all the fuses/fusible links.
now- when i put the key in, here is the series of events that happens.
turn key to acc, fuel pump primes.
turn key to start, fuel pump turns on, (sounds the same as when it is priming) which stops once i release the key.
once i release the key, the auxilliary cooling fan (injector cooler) turns on, and stays on until we remove the previously burned fusible link or remove the key.
just to be clear, we had no problems until plugging in the tachometer/oil guage (and a few other things that might be incorrect, but still matched the connector. particularly; one 3 prong T-Shaped connector under the steering wheel, and the long 2-row connection at the center of the back of the speedo cluster.
everything is now disconnected, fuses and fusible links replaced, problem persists. electrical gremlins make me want to crush the car with my bear hands.
P.s. i meant bear. not bare. if i had bear hands i would crush this thing.
#33
okay... so i have a bad alternator, and a weird problem... sometimes i will turn the car off and the injector fan stays on...
the car starts and runs fine, but in order to do this i removed fuses for everything except headlamps, tail lamps, turn signals, etc.
also... my tach no longer works, so thats fun. but now my speedometer does, since i replaced the cable and pinion gear. however, it is about 10mph slow at 70 mph. (compared to GPS)
the car starts and runs fine, but in order to do this i removed fuses for everything except headlamps, tail lamps, turn signals, etc.
also... my tach no longer works, so thats fun. but now my speedometer does, since i replaced the cable and pinion gear. however, it is about 10mph slow at 70 mph. (compared to GPS)
#34
This should happen when the coolant temp was ever over something like 230*F when running. Fully explained in the FSM.
You have to pull everything for the car to start? If you just try to start it without pulling, what happens?
Check coil wires (blue one is tach signal).
Check coil wires (blue one is tach signal).
#35
ok... so instead of removeing the oil pump we found the bolt on the back of the distributor which lets you adjust it further than the normal advance/retard. we loosened it up, and put in at center. (previous owner had it at full retard)
now we have the timing at 4~6 degrees BTDC (anyone know what it should be at 10:1 compression?) but it still wont start.
in order to do all this, we removed the distributor, replaced it, and unplugged the throttle body side of the vacuum lines that come from under the thermostat.
we replaced them, but i could have done it incorrectly.
more worrisome, is that while it was running, we didnt have the air filter attached. we now have the air filter attached. the afm cover popped off while we were installing it. could there be a problem there? with the air cleaner installed, would i have to decrease the idle set screw? im so lost right now.
should i not have moved the bolt on the opposite side of the distributor from the advance/retard adjustment screw?
now we have the timing at 4~6 degrees BTDC (anyone know what it should be at 10:1 compression?) but it still wont start.
in order to do all this, we removed the distributor, replaced it, and unplugged the throttle body side of the vacuum lines that come from under the thermostat.
we replaced them, but i could have done it incorrectly.
more worrisome, is that while it was running, we didnt have the air filter attached. we now have the air filter attached. the afm cover popped off while we were installing it. could there be a problem there? with the air cleaner installed, would i have to decrease the idle set screw? im so lost right now.
should i not have moved the bolt on the opposite side of the distributor from the advance/retard adjustment screw?
#36
ok... so instead of removeing the oil pump we found the bolt on the back of the distributor which lets you adjust it further than the normal advance/retard. we loosened it up, and put in at center. (previous owner had it at full retard)
now we have the timing at 4~6 degrees BTDC (anyone know what it should be at 10:1 compression?) but it still wont start.
in order to do all this, we removed the distributor, replaced it, and unplugged the throttle body side of the vacuum lines that come from under the thermostat.
we replaced them, but i could have done it incorrectly.
more worrisome, is that while it was running, we didnt have the air filter attached. we now have the air filter attached. the afm cover popped off while we were installing it. could there be a problem there? with the air cleaner installed, would i have to decrease the idle set screw? im so lost right now.
should i not have moved the bolt on the opposite side of the distributor from the advance/retard adjustment screw?
now we have the timing at 4~6 degrees BTDC (anyone know what it should be at 10:1 compression?) but it still wont start.
in order to do all this, we removed the distributor, replaced it, and unplugged the throttle body side of the vacuum lines that come from under the thermostat.
we replaced them, but i could have done it incorrectly.
more worrisome, is that while it was running, we didnt have the air filter attached. we now have the air filter attached. the afm cover popped off while we were installing it. could there be a problem there? with the air cleaner installed, would i have to decrease the idle set screw? im so lost right now.
should i not have moved the bolt on the opposite side of the distributor from the advance/retard adjustment screw?
Air filter should make a huge difference in idle speed
Rebuild the AFM if you haven't already an re-glue it with a proper sealant. I like shoe goo or Goop for the AFM since it lets you take it apart again if you need to otherwise it's water tight.
#37
ok. so it still wont start. i "rebuilt" the AFM, checked the timing, (we are at 8 degrees right now) fixed a minor fuel leak around my new pallnet, checked all my fluids, checked my plug wire order... so now, it will crank and crank, click a couple times and backfire. any other ideas? what could have changed? could it be that little black box on the side of the distributor? my timing light still flashes when it is attached and we crank it over.
#38
Back to the basics...
An engine needs 3 things to start (assuming it's mechanically sound):
-proper air
-proper fuel
-proper spark
Are all 6 injectors spraying fuel?
Are all 6 spark plug wiring sparking at the plugs?
Is the cam timed correctly to the crank?
An engine needs 3 things to start (assuming it's mechanically sound):
-proper air
-proper fuel
-proper spark
Are all 6 injectors spraying fuel?
Are all 6 spark plug wiring sparking at the plugs?
Is the cam timed correctly to the crank?
#39
yeah we've been punching ourselves trying to work it out.
i dont know how to check for proper air, although we have rebuilt the AFM, PLUGGED IT IN W/O the air box, with the air box, without the afm plugged in, and with the afm completely removed with no change.
the chain is timed correctly with everything, as we were driving it all over the place with the timing at 0 degrees btdc before we decided to fix the timing. (we wanted to run some 87 octane out of it while the timing was so retarded, so we could put premium in it)
we dont know how to check if they are spraying fuel, (without getting it everywhere) but with a 9v, they actuate.
are the plug wires sparking at the plug? i will go check that right now. the timing light flashes on plug 1, and the spark happens at the ignition coil, however.
heres the new series of events- we stopped to adjust the timing. we used the light and at full advace, we were at tdc for the spark. we removed the distributor completely, found the upside-down bolt, and moved it to the center. (the one opposite the advance/retard setting) then re-attached the distributor.
(we removed the vacuum lines that dangle below the distributor that lead to the throttle body, however, so if i installed them incorrectly, could that be the problem?)
we adjusted the distributor to be at 8 degrees btdc, re-attached the vacuum advance hose, plug and wire, then re-attached the aforementioned vacuum lines.
so there you have it. i will check the wires now. be back in a moment.
i dont know how to check for proper air, although we have rebuilt the AFM, PLUGGED IT IN W/O the air box, with the air box, without the afm plugged in, and with the afm completely removed with no change.
the chain is timed correctly with everything, as we were driving it all over the place with the timing at 0 degrees btdc before we decided to fix the timing. (we wanted to run some 87 octane out of it while the timing was so retarded, so we could put premium in it)
we dont know how to check if they are spraying fuel, (without getting it everywhere) but with a 9v, they actuate.
are the plug wires sparking at the plug? i will go check that right now. the timing light flashes on plug 1, and the spark happens at the ignition coil, however.
heres the new series of events- we stopped to adjust the timing. we used the light and at full advace, we were at tdc for the spark. we removed the distributor completely, found the upside-down bolt, and moved it to the center. (the one opposite the advance/retard setting) then re-attached the distributor.
(we removed the vacuum lines that dangle below the distributor that lead to the throttle body, however, so if i installed them incorrectly, could that be the problem?)
we adjusted the distributor to be at 8 degrees btdc, re-attached the vacuum advance hose, plug and wire, then re-attached the aforementioned vacuum lines.
so there you have it. i will check the wires now. be back in a moment.
#42
ok. so we have spark, we have fuel, we (presumable) have air, and yet all we are getting is a backfire. could we have slipped a link on the timing chain? it seems like we would be hearing valves smacking the piston if that were the case.
im thinking theres gotta be something im missing. and it is driving me up a wall. i just want it to drive!
im thinking theres gotta be something im missing. and it is driving me up a wall. i just want it to drive!
Last edited by ZZzzz; 09-03-2012 at 06:29 PM.
#44
yep. and the timing light says we are at 8 degrees btdc. im lost.
edit: we re-gapped the plugs before this mess and they are at .034, because i read that you need to shorten the gap to get it to spark under higher compression. it ran fine before, is there some reason i might want a smaller gap even than this?
edit: we re-gapped the plugs before this mess and they are at .034, because i read that you need to shorten the gap to get it to spark under higher compression. it ran fine before, is there some reason i might want a smaller gap even than this?
#45
have you checked the cylinder head temp sensor? that sensor alone will cause the same problem you're having at the moment. If it's not that check the air flow meter's spring tension. If it's too tight or too loose it will run wrong also.
#46
i am ashamed.
i found the culprit.
i also did the impossible.
we installed the distributor backwards.
180 degrees off.
incidentally, 180 degrees will make you read your timing as correct even though it is completely backwards, because on a 4 stroke, the crank rotates twice for each rotation of the camshaft. i dont even know how it went on that way, but the problem is resolved.
now, with the timing correct, (8 degrees btdc) the thing pulls so hard it makes me giddy. next stop is brakes and suspension.
anyone looking to get rid of a rolling chassis with no rust holes and/or major dents? i'll post some pics of my z soon so you guys can ask me why im wasting my time. lol.
i found the culprit.
i also did the impossible.
we installed the distributor backwards.
180 degrees off.
incidentally, 180 degrees will make you read your timing as correct even though it is completely backwards, because on a 4 stroke, the crank rotates twice for each rotation of the camshaft. i dont even know how it went on that way, but the problem is resolved.
now, with the timing correct, (8 degrees btdc) the thing pulls so hard it makes me giddy. next stop is brakes and suspension.
anyone looking to get rid of a rolling chassis with no rust holes and/or major dents? i'll post some pics of my z soon so you guys can ask me why im wasting my time. lol.
Thread
Thread Starter
Forum
Replies
Last Post
Bookmarks