90' 300zx non turbo - Infamous Nissan

nismo_sean · 03-02-2014, 05:48 AM

so i bought this car with the intent of fixing it up and auto-x ing the crap out of it..

here's the pics from the craigslist ad..

long story short, it ran (barely) when i bought it, i made it about 7 miles before it sounded awful and lost power and hitting the gas made it die..

i towed it home and got it in the garage..

took out these awful seat covers, lol

and got started pulling the motor apart to diagnose it..

the timing belt was intact(thank god) but it was a tooth off, not really surprised it ran like shit, lol

got it back in time counted the teeth on the belt like 6 times, even marked it lol did a leakdown test, and to my dismay the results came as so..

cylinder #1 - nothing, leaking out intake valve
cylinder #2 - 80% leakage, intake valve
cylinder #3 - nothing, intake vale leak
cylinder #4 - 25% leakage, good
cylinder #5 - 25% leakage, good
cylinder #6 - 80% leakage, intake valve

soo im pretty dissapointed with those results, i got the intake plenum off(what a pain in the a$$) and i pulled the intake valve covers, couldnt really see anything

i guess tomorrow i will continue teardown.

i really hope a full head rebuild with all new valves and lifters isnt required, i cant afford that, lol

nismo_sean · 03-02-2014, 05:49 AM

more pics

nismo_sean · 03-04-2014, 10:50 PM

so, im getting antsy wanting to pull the motor out and see the damage, but its friggin' 15 degrees outside...

i cant wait until summer..

but i want to drive it this summer, lol i just can't win..

97_hardbody · 03-07-2014, 01:20 AM

Damn. That was my dream car in high school too. What plans you have for the motor now? just doing a rebuild and keeping it stock or adding power for your auto-x enjoyment?

nismo_sean · 03-07-2014, 03:24 AM

internals will be stock, but i would like to do headers back, full exhaust, and maybe some motor mounts, mostly i will be doing suspension mods to make the most gains though..

..not much progress yet, lol, its been sleeting all afternoon and theres a layer of ice on the driveway maybe 3/4 inch thick so far.
i did get the cat back section of the exhaust off earlier though.
hopefully i can get the trans out this weekend..

nismo_sean · 03-07-2014, 03:27 AM

also after some thorough research i found that the early models (such as mine) the intake valves were made of a softer inferior metal and were prone to wear and bending

i also found a guide on how to clean/rebuild the hydrolic lifters, that alone could save me $700!

i am already expecting to replace all the intake valves, maybe(hopefully wont need to) replace the exhaust valves.

new rings and bearings for the bottom end while i have the motor out and apart..

this will probably turn into a very slow build..

nismo_sean · 03-14-2014, 10:04 PM

so here is where im at going into this weekend, got the exhaust off..

make a very wobbly extension...

...and pulled the trans.

the head bolts were M10 allen keys...

that was fun...

three easy steps..

1

2

3

good intake valve on right, bad one on the left...

alabama_lowlife · 03-14-2014, 11:11 PM

Go ahead and replace the efi harness and all the damn fuel injectors while you have it apart!! I'm not even playin, save yourself some MAJOR headaches later.

nismo_sean · 03-15-2014, 03:01 AM

yes, i am definately replacing the efi harness, probably the alternator to trans harness too...

nismo_sean · 03-26-2014, 02:59 AM

UPDATE!!

found a silver paint factory... :/

heres a video of what rod knock sounds like...

03-14-2014, 11:11 PM	#8
alabama_lowlife Owner and Administrator Join Date: Sep 2008 Location: jack, alabama Age: 39 Posts: 9,505 Vehicle: 08 altima, 1970 Datsun 521, 1995 Nissan Hardbody x2 Thanks: 730 Thanked 1,769 Times in 1,457 Posts	Go ahead and replace the efi harness and all the damn fuel injectors while you have it apart!! I'm not even playin, save yourself some MAJOR headaches later. __________________

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03-02-2014, 05:48 AM	#1
nismo_sean Join Date: Jun 2012 Location: greensboro, nc Posts: 205 Vehicle: 95 hb Thanks: 55 Thanked 21 Times in 18 Posts	90' 300zx non turbo so i bought this car with the intent of fixing it up and auto-x ing the crap out of it.. here's the pics from the craigslist ad.. long story short, it ran (barely) when i bought it, i made it about 7 miles before it sounded awful and lost power and hitting the gas made it die.. i towed it home and got it in the garage.. took out these awful seat covers, lol and got started pulling the motor apart to diagnose it.. the timing belt was intact(thank god) but it was a tooth off, not really surprised it ran like shit, lol got it back in time counted the teeth on the belt like 6 times, even marked it lol did a leakdown test, and to my dismay the results came as so.. cylinder #1 - nothing, leaking out intake valve cylinder #2 - 80% leakage, intake valve cylinder #3 - nothing, intake vale leak cylinder #4 - 25% leakage, good cylinder #5 - 25% leakage, good cylinder #6 - 80% leakage, intake valve soo im pretty dissapointed with those results, i got the intake plenum off(what a pain in the a$$) and i pulled the intake valve covers, couldnt really see anything i guess tomorrow i will continue teardown. i really hope a full head rebuild with all new valves and lifters isnt required, i cant afford that, lol

03-02-2014, 05:49 AM	#2
nismo_sean Join Date: Jun 2012 Location: greensboro, nc Posts: 205 Vehicle: 95 hb Thanks: 55 Thanked 21 Times in 18 Posts	more pics

03-04-2014, 10:50 PM	#3
nismo_sean Join Date: Jun 2012 Location: greensboro, nc Posts: 205 Vehicle: 95 hb Thanks: 55 Thanked 21 Times in 18 Posts	so, im getting antsy wanting to pull the motor out and see the damage, but its friggin' 15 degrees outside... i cant wait until summer.. but i want to drive it this summer, lol i just can't win..

03-07-2014, 03:24 AM	#5
nismo_sean Join Date: Jun 2012 Location: greensboro, nc Posts: 205 Vehicle: 95 hb Thanks: 55 Thanked 21 Times in 18 Posts	internals will be stock, but i would like to do headers back, full exhaust, and maybe some motor mounts, mostly i will be doing suspension mods to make the most gains though.. ..not much progress yet, lol, its been sleeting all afternoon and theres a layer of ice on the driveway maybe 3/4 inch thick so far. i did get the cat back section of the exhaust off earlier though. hopefully i can get the trans out this weekend..

03-07-2014, 03:27 AM	#6
nismo_sean Join Date: Jun 2012 Location: greensboro, nc Posts: 205 Vehicle: 95 hb Thanks: 55 Thanked 21 Times in 18 Posts	also after some thorough research i found that the early models (such as mine) the intake valves were made of a softer inferior metal and were prone to wear and bending i also found a guide on how to clean/rebuild the hydrolic lifters, that alone could save me $700! i am already expecting to replace all the intake valves, maybe(hopefully wont need to) replace the exhaust valves. new rings and bearings for the bottom end while i have the motor out and apart.. this will probably turn into a very slow build..

03-14-2014, 10:04 PM	#7
nismo_sean Join Date: Jun 2012 Location: greensboro, nc Posts: 205 Vehicle: 95 hb Thanks: 55 Thanked 21 Times in 18 Posts	so here is where im at going into this weekend, got the exhaust off.. make a very wobbly extension... ...and pulled the trans. the head bolts were M10 allen keys... that was fun... three easy steps.. 1 2 3 good intake valve on right, bad one on the left...

03-15-2014, 03:01 AM	#9
nismo_sean Join Date: Jun 2012 Location: greensboro, nc Posts: 205 Vehicle: 95 hb Thanks: 55 Thanked 21 Times in 18 Posts	yes, i am definately replacing the efi harness, probably the alternator to trans harness too...

03-26-2014, 02:59 AM	#10
nismo_sean Join Date: Jun 2012 Location: greensboro, nc Posts: 205 Vehicle: 95 hb Thanks: 55 Thanked 21 Times in 18 Posts	UPDATE!! found a silver paint factory... :/ heres a video of what rod knock sounds like...