Help plz, car cranks but no start after droping rebuilt motor in

[Khaserwolf]

I have a 78 280z, took the motor out with a few friends, we rebuilt her and droped the motor back in 3 months later but it wont start, it cranks over but wont start. we ran test, it has fuel, and spark but it wont start. The test show the spark is bit weak from the coil. Now also we hooked the starter up exactly the way it sapose to from pictures took before uninstall. but now the starter turns with out having foot on clutch and it sounds week. we took it up to a auto zone, ( i must mention, I hate auto zone lol), they tested it and said the starter is still good. Would a slow turning starter be a issuse, is there any thing u think i missed hooking up that would provent it from not starting, Any help would be very very much welcome. This is my first Z and I love the car and i only got to drive it for 3 weeks before we was forced to tear it down.

[loy]

Make sure your timing is correct. Maybe the distributor is off by 180?

[Khaserwolf]

well we re did the timming twice and it did the same thing with each time we redid the timming, the distribitor is pointing at cylinder 1, piston one is top dead center. lol heck im even thinking of trying to put more gas in it just in case, oh yea, my gas gage seem to be stuck on 1/4th a tank lol. i got the car off a online add and I realized i bought some one else problem lol

[Zmanco]

With the engine at TDC and the dizzy pointing to #1, pull the valve cover and make sure that both the cam lobes for #1 are pointing up and not depressing the valves. The most common problem is to mount the dizzy 180 degrees off. Just making sure that it points to #1 when the damper shows TDC won't catch this and you'll never get it started.

[jacob80]

If you're sure you're getting spark and fuel, then it has to be a timing issue (whether it be mechanical or electrical).

 

Follow ZManco's advice and you'll be alright

[Khaserwolf]

ok ill take a look at it and let u all know what position its at.

[GOTHALOSISM]

Also 1,5,3,6,2,4 counter clockwise

 

Make sure you have a fully charged battery as well.

[ktm]

Also 1,5,3,6,2,4 counter clockwise

 

Make sure you have a fully charged battery as well.

 

Thank you. Check your firing order as Goth mentioned. It's easy to get the plug wires confused.

 

A weak battery can cause issues with the starting as well. If the engine can't spin fast enough to develop sufficient compression, the car won't start.

 

Have your battery checked (a load check at your favorite "Zone") and check the connections (ground and power).

[Khaserwolf]

ok i see the timing is still way off, we will work on that tomarrow, but would a weak starter also hurt it as well? the battery is still reading 12 volts

[dagold]

Make sure your grounds are good.

[hoov100]

[beebeecivic]

If your gas guage is not working, the fuel sender unit my be full of rust aka your tank is rusted. Probably wont solve the problem but worth taking a look at.

[Khaserwolf]

ok i got the motor the the zero mark on the timming and open the cyl. ! spark plug and its at top dead center.but i looked at the cam and it seems off and the timming mark that on that v grove is way off. so would that make it not start. I know u all will probably say yes but im asking any ways, im still new lol also i see the diagram picture of the dis. cap you put up and ill cheak that in the moarning. So once i get timming right, what else would make it not start. Any thing with the vaccum lines? i really need a vaccum line diagram lol

[Khaserwolf]

ok so i took the front cover off, (Gurrr) and No the 2 lobes was not what they was sapose to be, so im starting over all over again, i just pary i dont snap any more bolts, lol i already snaped 2 bolts. If this cover have to come off again after this im buying new bolts lol. Any ways, so i was also looking on another topic about timmming and saw this video. Timing video

 

 

And I hope that a is right for my 280z. Because if so later today im going to try timming it just like that. only think, the gear on the crank, that sapose to have a notich on it, would any one know how i would find it? but atm the camshaft 2 front lobes on cyl. 1 is completly off the springs.

[Orangy]

Seeing how this is a '78 and assuming its still EFI, check the wiring. There's a red wire that goes from the negative battery terminal and grounds to the firewall. If that wire isn't hooked up you won't start up. It's for the EFI system. I had that happen when I changed my clutch last year. Took me forever to figure that out.

[Khaserwolf]

Seeing how this is a '78 and assuming its still EFI, check the wiring. There's a red wire that goes from the negative battery terminal and grounds to the firewall. If that wire isn't hooked up you won't start up. It's for the EFI system. I had that happen when I changed my clutch last year. Took me forever to figure that out.

REALLY NOW, i dont remmber seeing it, any way you could provide a picture. I honestly dont remmber seeing it

Edited August 7, 2010 by Khaserwolf

[ModernS30]

How are you sure you are getting fuel? Try starting it on starter fluid. Are all of your sensor hooked up? It sounds very much like a timing issue. Especially what you were saying about the cam. Some of your posts are kinda hard to understand. Grounds will for sure cause it not to start. How did you check spark?

[Khaserwolf]

Ok after redoing the timming best i could, put the car back together, it doing the same thing. Ok after cheaking every thing

 

1. Yes we got spark to the spark plugs

2. we hooked up a diffrent battery to the car and the starter sounded stronger but still no start. And after disconection and reconecting the starter, it still tries to start when key turned, with out the clutch being pressed down.

 

3 now for ssome reason im not hearing the fuel pump, but it was working before we took car apart. Now i getting fuel from the fuel line at the filter. but it dont seem strog of flow when pump on like it use to.

 

4. I still havent found a red wire then grounds the negative to the engine block, so i made a ground to do that and still nothing lol.

 

How would I check if the injectores are fireing? or is there any thing else that would make then not fire??

[Pharaohabq]

There's only a few things that would cause your engine not to run. 1 Fuel, gotta have it to burn. 2. Spark, gotta have it to ignite the fuel. and 3. Proper timing. Assuming you have compression and all since you just rebuilt the motor.

 

Fuel, You will need to get some hose and a gas can, take loose the fuel line from the engine, and run it out to the gas can, Be careful here, GAS IS FLAMABLE AND DANGEROUS. but you'll need to run it and ensure a good flow. If not, you'll likely need to replace your fuel filter, or worse clean out your gas tank and replace filter and pump.

 

Spark, When you've got your fuel lines cleaned out and reconnected and all gas is enclosed safely away, you can pull off a plug wire and put it on a spare plug, balance it on your vavlecover and see if it sparks when you crank, no spark, = likely bad coil/wires/dist rotor/cap.

 

As for the timing marks, Check out the timing picts on this guy's car domain page: 280z timing pict page You'll see all the timing marks you need. I think also on the back of the upper gear there are two marks that aren't shown that should be level with the head. If you make sure those all match you should be good on the timing. As for busted bolts, you should replace the busted ones unless you want oil leaks. And stop over tightening your valve cover and it won't strip and sieze your bolts.

 

Good luck and hope you get it started. Oh the Haynes manual or the FSM are really helpful for this.

 

Phar

[Khaserwolf]

Ok so we found oit the injectors are getting no power, we hooked a noid light up and saw it wouldnt even light up. So im going to take all the wires alose and re hook every thing back up. So any advice of what u think is the main thing for the harness. Yes im useing the stock 78 fuel injection set up.