240z cranks but won’t start

[Idontknowwhatimdoing]

So I recently rebuilt my spare l24 by replacing main/rod bearings, piston rings, head gasket, oil pump, water pump, timing chain/sprocket/tensioner/guides, valve stem seal gasket, distributor stator/ ignition control module, ignition coil, plugs/wires... I’m sure I’m missing a few things but I’m sure you get the gist. 

I haven’t had any luck starting the engine. Starting fluid just makes the car backfire through the exhaust 

My l24 has triple Weber 40 DCOE’s (NOT running chokes or vacuum advance) a 280zx distributor and the rest is pretty much stock. The engine does have compression.

SPARK  

I have checked spark with a spark tester and I have spark in ALL the cylinders. 

FUEL 

I have confirmed that the carbs are spraying fuel into the intake chambers. Plus I have disconnected the fuel line to the carbs to make sure they are receiving fuel. 

TIMING

I believe I have set the engine in the correct TDC and have included pics for verification. 

 

Any advice and information would be greatly appreciated!

 

 

Edited November 21, 2018 by Idontknowwhatimdoing

[Zed Head]

Things look about right.  How about valve lash?  Any chance it's too tight and you have valves hanging open?

You didn't show firing order either, or rotation direction.  I've put my wires on backwards before.  The engine actually started but it ran like the wires were on backward.

[Idontknowwhatimdoing]

I will double check the valve lash, I adjusted them when I threw the head on. As far as the firing order I have them at 15-36-24 counter clockwise 

[Zed Head]

Have you tried rotating the distributor to a new spot?  Your picture of the distributor shows the trigger wheel in a position that will give retarded ignition timing.  If the timing mark is on zero then it's going to be very retarded for starting and running.  Turn the distributor body clockwise and that should advance your timing.  By the time the damper mark is on zero the spike on the star should have already passed the spike on ring.  

[Idontknowwhatimdoing]

Nice eyes! I was actually messing with the position of the distributor today. When I would advance it, the car would just crank, no backfires, no strange noises just crank. However I never fully advanced the timing through the dizzy (had to charge the battery) I will advance the distributor timing once the battery is charged. Thanx for the speedy replies 

[Idontknowwhatimdoing]

22 minutes ago, Zed Head said:

By the time the damper mark is on zero the spike on the star should have already passed the spike on ring.  

I am unfamiliar with this terminology. Can you explain?

[Zed Head]

I was just giving too much detail.  When the two spikes pass each other is when spark will happen.  Based on where the spikes are your ignition timing is retarded.  Marked up the picture, below.

I think that it might start if you advance your ignition timing.  Loosen the adjustment screw at the base of the distributor and rotate the distributor body slightly clockwise while you're trying to start it.  You can do it with everything assembled you don't need to see the internals. 

It's actually pretty common to have to move the distributor back and forth to find the spot that will start the engine, after reassembling everything.  Then use your timing light for the final setting.

[SteveJ]

The distributor is WAY out of wack here. Please note in the attached photo where the vacuum advance is on my distributor (ZX distributor).

You need to take a few steps back. Make sure you're at TDC on the compression stroke, align the oil pump properly and re-install the distributor.

Did your car always have the ZX distributor, or did you do the conversion? Was a ZX distributor mounting block used?

[240260280]

Yup, your spindle seems to be off.  Set crank to 0degrees (TDC). Pull the distributor, then share a photo of the top of the spindle, it should look like this:

 

[SteveJ]

2 minutes ago, 240260280 said:

Yup, your spindle seems to be off.  Set crank to 0degrees (TDC). Pull the distributor, then share a photo of the top of the spindle, it should look like this:

I need to remember to archive that photo. Of course, I was hoping you'd see this thread and post that photo.

[240260280]

11:25 is more like 11:27 

[grannyknot]

3 minutes ago, 240260280 said:

11:25 is more like 11:27 

Pacific Standard Time of course for Seattle.