Bense's H23A Swap HowTo & Discussion Thread.

Swap is certainly still being worked on about every other day. I have taken my time with every single step along the way. Things that are covered in grease, crud have been purple powered and scrubbed. Rather than extending the CKP sensor wires over to the distributor, I unwrapped my harness section by section and re-threaded the CKP wires back towards the distributor. I did the same with the o2 sensor plug, and whatever else needed it.

So far, in this project I have:
* replaced timing belt and water pump
* h23a1 manual timing belt tensioner swap
* removed balance shaft belt
* removed IAB butterfly plate
* rebuilt my F23A1 transmission with h23a1 gears (usdm final,3rd, 4th, jdm 5th)
* replaced clutch and pressureplate
* removed catalytic converter (it was the easiest way to get the header mounted to the exhaust)
* made a "custom" distributor adapter harness that allows me to plug my original accord f23a1 harness into the JDM distributor.
* replaced driver side outer CV boot.
* Replaced most hoses, new alternator/ac belt.
* Replaced radiator (found out original was cracked and had been JB welded.)
* Made a throttle cable adapter bracket.


To do:
* Find my chips so I can burn the H23A ROM that Blundar sent me.
* Re-wire 3-wire IACV to work as 2-wire until I can get an OBD1 2-wire IACV adapter plate.
* Move F23A1 dual throttle cable pulley over to H23A throttlebody.
* Filter for the intake.


I attempted to start the vehicle with the OBD2B H23A automatic ECU. Engine just turns over and doesn't fire. I tried starting with the F23A1 PAA ECU (just to see if the engine will idle) and I smell fuel. It doesn't fire and there is a fuel leak somewhere in the engine bay, I am unsure where.

I have read that others have had to wire in a resistor box for the JDM injectors, I am not sure if this is needed for these. If so, would using my original F23A1 injectors prevent me from having to do this?

I currently have the barb that comes out the top of the throttlebody hooked up to the EVAP canister valve, which then has a hose to a black plastic cylindrical component (I assume that it's a check valve), that is then connected to a fuel return line.

The other fuel line that is connected to (I guess it's the FPR) with the two 10mm head (M6-1.0) bolts onto the fuel rail is the one that was originally on my F23A1. Perhaps I should put the H23A on instead.

The larger fuel line has one washer between the hose banjo fitting and the fuel rail, then there is one uniquely shaped washer between the fuel line banjo fitting and the 22mm nut nut that fastens the fuel line to the fuel rail. This seems to correspond with the inadequately documented factory service manual.

If anyone has any suggestions for my fuel leak, please advise. I have a plethora of pictures, but I am attempting to hold off bombarding this post with unnecessary clutter.

That's weird, my paa ecu was able to start my h23a as a temporary solution. And there's no need to wire in a resistor box

Love the build. I have an H23A myself....well now my wife does and she loves it.

Ok maybe i can shine some light on your problems hope i can be of assistance. If i remember correctly it should be wierd washer fuel line washer and lil mushroom filter. I had a fuel leak at that same exact spot. And the fpr please put the h23 back on sohc and dohc have a slight difference atleast mine did yours could be different. Also check for the dizzy wiring check to see if the braided wire that surrounds the original ckp,tdc, etc is grounded very important. This kept my car from sparking for 5 months. Hope that helps good luck and keep up the good work.
P.s. sorry for runon sentences

I found the culprit of my fuel leaks. I mounted the FPR upside down. Oops.

Engine started with the F23A1 PAA ECU, and ran smooth long enough for me to gently move the car off of the ramps that were under the rear wheels. I pulled the ramps out, and moved the car out of the car bay.

I'll need to get some fuel hose, find a way to mount an air filter, and find my eproms.

Okay.

Removed the buttlerfly plate


Swapped out JDM H23A (left) with the Accord F23A1 (right) oil pressure sensors so that I didn't have to change the plug on my F23A engine wiring harness.


All of the F23A1 internal distributor wiring in one shot.


Reworking the engine harness.


H23A1 manual tensioner conversion.




New clutch and pressure plate


Gasket arrived and installed the upper intake manifold plenum with five d-series transmission housing bolts.


Transmission mess


Breaking 4.05 ring gear loose.


Yours truly


New lipstick


4.266 ring gear installed. I put a minuscule amount of paint on the gears that I would be using.


Finishing up the hybrid trans



Countershaft snap-ring locked in place, refreshing positive sign.

Trans mounted


Been cleaning the bay


Getting hoses routed and ready, as well as installing the half shaft and writing harness.


Here goes nothing...


Mounted



NO modification required when using the JDM H23A aluminium timing mount bracket.


Bubba helped too


I chopped the ends off of the catalytic converter, got this coupler from autozone with the ubolts and lined everything up Accordingly (pun intended).


Replacing the torn boot on my CV axle


Exciting!


Exhausting efforts


Found a pinhole in the oil pan.


Fixed


Distributor conversion harness that I made.

I really like your distributor sub-harness idea! I think you said that you pulled the original harness up from the lower front of the engine to plug into that adapter harness- That's just frigg'n awesome.

Craize said:

I really like your distributor sub-harness idea! I think you said that you pulled the original harness up from the lower front of the engine to plug into that adapter harness- That's just frigg'n awesome.

Click to expand...

On my F23A1 harness I clipped the CKP plug off, and gave myself ample length knowing that I'd be re-soldering it. I then undid my harness and pull the wires all the way over to the distributor area.

With that plug, and the original F23A1 distributor plug I made the plugs that stayed connected to the F23A1 harness.

I then took apart my F23A1 distributor and used the plug on it, and the internal wiring, along with a plug that I retrieved from an old 4-wire o2 sensor and soldered it to the distributor harness plug that I cut off of the JDM H23A harness.