KA24DE new swap in Datsun 620 - no start condition.

[620_Brian]

I have a separate "build thread" somewhere here an Ratsun but I felt this needed its own.....

 

Sorry for the long post but I want to get all the data out there to help get this resolved.....

 

Over the past year, I have entirely rebuilt a 96 KA24DE and swapped it into a 79 Datsun 620. 

Bottom end and head was assembled by the reputable shop that did the machine work,.

I did timing assembly and torqued down the head myself.
It has the standard KA/240 5 speed behind it (also rebuilt).
Wiring Specialties harness custom made for this application and a 96 KA Auto ECM.
Everything is plugged in and terminated per wiring specialties documentation.
Grounds all over the place, chassis, body, starter, alt, ecm.
Brand new battery.

Proper S14 dizzy.
Good spark on all 4.
Walbro 255 FP and a Tomei FPR set at around 40psi.

Stock KA red injectors (I think).
Triple checked the timing - i.e. - I put it at TDC with the finger in the #1 hole trick, long ratchet extension dropped in plug hole is at its top movement.

Crank pulley is on 0deg, the #1 
Cam lobes are pointing out at TDC (pics below).

Also did a noid test - injectors are flashing (vid below) and I removed the fuel rail and rigged up water bottles under each injector. They all spray while cranking (a LOT actually).

 

I just cant get it to start / idle on its own. 

 

some pics / vid:

TDC cams:

TDC crank pulley:

FPR:

 

NOID vid:

 

 

What am I missing?
Any help is greatly appreciated.

 

Dumb theory - Its almost like the injectors are spraying TOO much and flooding the cylinders - like its not presenting an nice atomized spray on the compression stroke - its more like a giant puddle that the plugs cant ignite? I don't know.

 

Edited August 23, 2019 by 620_Brian

[]2eDeYe]

Have you pulled the plugs after cranking to see if they are wet and fouled?

 

 

[620_Brian]

Yes I have and yes they are very wet - still sparking after a good drying though.

 

Note -  I do plan on changing the oil right away once I get it to start/ idle  because I'm pretty sure there's gas in the oil from all this cranking and flooding.

Edited August 23, 2019 by 620_Brian

[]2eDeYe]

You're positive the dizzy isn't 180 out?

 

[Stoffregen Motorsports]

Does this motor have a cold start injector?

 

I had a similar problem years ago and I'm trying to remember the cause. I know there's a way to fire the injectors off manually. That had something to do with it.

 

Hopefully you get it figured out by the time I remember...

[620_Brian]

Yes I'm positive the dizzy is correct - in fact I've torn the front of the motor off twice now this week second guessing myself.

Everything lines up perfectly and in time. TDC, dots on sprockets, marks on chains, cams pointing out.

When I continuously crank it with a timing light connected, the light flashes perfectly on 0deg mark, dizzy is within its adjustment hole.

Also with the noid light in the injector #1 plug I can slow down the vid and see the noid in sync with the 0deg timing light flash.

Like I said ^ I have even removed the fuel rail, rigged up water bottles and watched all 4 injectors spray.

It looks like its way to much of a spray to me but whatever.

 

One other thing - I can get it to sort of run with the injectors unplugged and spraying start fluid...

 

Stoffregren - I removed all of the IACV stuff off the back of the intake manifold and made block off plates during the build....I was told it runs fine without.

The intake literally has two vacuum ports - one for the brake booster and one for the FPR.

 

I bought new plugs today..I'm going to reassemble everything again so the MAF and the IAT are sending something to ECM and try it again.

Ill grab some codes after that and go from there...

Ill post a new video of what I find..

My neighbors are going to hate me - open header!

 

I also have some other injectors to try but they are the purple SR versions - probably way to much flow.

 

Open to any other suggestion too.

 

"get a KA they said, it runs on like 6 wires they said, it'll be great they said" 🙄

Edited August 23, 2019 by 620_Brian

[datzenmike]

Wouldn't the spark plug fire slightly advanced of TDC? and wouldn't the injector squirt fuel before that? Fuel has to be in and mixed before spark

 

 

 

[620_Brian]

Well..IF I have the dizzy set to 0deg TDC based on the timing light flash on the crank pulley, it fires at exactly the same time at the injector.

I assume that's what the dizzy adjustment is for - if its set at 0deg then they are in sync.

Not where you want it for a running engine of course, just as a test that im in time.

Then you'd adjust it to 20deg or whatever to dial it in.

Am I assuming correctly there?

 

Edited August 23, 2019 by 620_Brian

[datzenmike]

Don't know but I would think the fuel has to be there first. It may be a function of the timing setting. 0 seems a little late to me. My L20B is 12 BTDC and starts. 

 

Hey I have no idea with EFI just throwing shit at the wall to see if any sticks.

[620_Brian]

👍

[]2eDeYe]

Sounds like it''s fuel if you can get it to run on starting fluid. What's the history on the injectors you are using?

 

[620_Brian]

They came with the “free” KA I got. 

Theyre about the only thing still original so ya.

They’re suspect. 

[datzenmike]

Runs 'sort of' on starter fluid proves it runs and ignition is there and close to correct of not totally correct. Again, if the gas is one millisecond after the spark it won't light. Probably won't light during either. 

[620_Brian]

Righto.

So now that I’ve proven in theory that the timing is there at 0 DEG TDC  with the noid light and the timing light (exactly in sync), I just have to twist the dizzy to get the proper running timing.

I think the FSM calls for 20 DEG BTDC or something.

[datzenmike]

could be 20. The CAS sets the running timing.

[620_Brian]

Set the timing per FSM. 

Got it running by unplugging the CTS (it’s original also, and tested bad), new plugs and turning the FPR down to 10psi. 
I’m going to order new injectors I guess?
Not really sure what this fuel delivery problem is. 

[thisismatt]

Why don't you replace the CAS before injectors?

[620_Brian]

The CAS is in the distributor on this one.  

Not really serviceable from what I understand. 

I have 2 - S14 dizzys.

They both act exactly the same. 

Unless there’s something I don’t know about the CAS?

[thisismatt]

Sorry, misread your comment about the CTS.  

[620_Brian]

brap brap

 

[Trophy24]

Success!

[620_Brian]

Bad injectors. Problem solved. 
See my build thread for joy. 

[banzai510(hainz)]

Dude that is bad ass nice looking motor!