Performing Honda K24a3/AST5 6spd Conversion

Rear Hub Bearing Replacement here

FInished the wiring connections coming from the cabin to the motor harness working on it yesterday & today. Been sick, so not much energy to put into working outside of work.

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I made a list of how I was going to wire this, and I STILL had to go over it a few times & reset the pin locations due to mix-ups. Anyway, that part is done now.

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One of the wires I am repurposing is the grey/yellow that was the injector fan ground loop. I'm going to be using it for the ECU cooling fan relay ground signal. That wire is coupled with the OP idiot light, and meet at the fusebox. No practical way to determine which is which, so I just cut one & hoped it was the one I needed to isolate. I lucked out :D

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After that, I decided separate the transaxle from the motor & take it back apart

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Can't find anything wrong with it.

Shift gates & forks look fine, turning the shafts turns the diff

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Put the case back on temporarily & checked movement


I thought maybe I had locked it in reverse, but there is no practical way for that to happen. Cleaned up the case, applied new HondaBond, re-assembled, and checked movement at the diff in all gears. I can rotate the output in all gears except reverse. I hope that's just cos of the gearing & insufficient leverage.

When I installed the detent pin for the shift gate, and the speed sensor, the diff wouldn't turn again. Pulled out first the detent pin, still locked. Removed the speed sensor, diff turns just fine. This really sucks cos if I had just removed that first & checked the diff I probably would not have needed to dismantle it.

Tip of speed sensor is damaged. Not sure how this became an issue, as the sensor is original, the gear arangement is unchanged.

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I measured the depth off the casing to the gear, and it's just shy of 44mm

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Hopefully the new sender is about 1mm shorter - I'm not taking it apart again :D
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Yikes! Good luck with the trans Hussein. For a guy who is sick, you got a lot done today.

Oh, and regarding your wiring - I remember way back in the day I did some custom wiring on my first '76 X1/9 where I swapped in an '81 FI engine but didn't bother to upgrade the wiring harness 'cuz the junkyard wanted (at the time) a "ridiculous" $100 for a wiring harness, so I made my own. I added an addendum to the Haynes or Chilton wiring diagram with the mods I made. I totally recommend doing that.

Keep up the good work and thanks for posting!
 
Perhaps a shim under the plastic mounting boss of the sensor to lift it up the required 1mm. Or is there something inside the trans which during your rebuild has eaten up the 1mm you require? (I know not what you want to hear).

Bummer in any case.
 
Perhaps a shim under the plastic mounting boss of the sensor to lift it up the required 1mm. Or is there something inside the trans which during your rebuild has eaten up the 1mm you require? (I know not what you want to hear).

Bummer in any case.

Nothing that can have moved in the trans - it picks up off the gear, which cannot move relative to the casing, that's for sure. I must have dislodged the tip, allowing it to contact the gear, and once that happened, it's all over. I'll know for sure over the weekend. Shimming it would be next. I'm not taking the case apart again.

I mated the transaxle with the engine again, put it back on the subframe.

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found a spot to use for the bayfan temp sender - in this location I can pivot it in or out of the manifold heat to adjust fan onset if needed.

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Yikes! Good luck with the trans Hussein. For a guy who is sick, you got a lot done today.

Oh, and regarding your wiring - I remember way back in the day I did some custom wiring on my first '76 X1/9 where I swapped in an '81 FI engine but didn't bother to upgrade the wiring harness 'cuz the junkyard wanted (at the time) a "ridiculous" $100 for a wiring harness, so I made my own. I added an addendum to the Haynes or Chilton wiring diagram with the mods I made. I totally recommend doing that.

Keep up the good work and thanks for posting!

Hey Darin

Neglected to respond - yes, for the wiring I make diagrams for any changes I make - otherwise I'd never remember what is what :D

Usually like this:

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Nothing that can have moved in the trans - it picks up off the gear, which cannot move relative to the casing, that's for sure. I must have dislodged the tip, allowing it to contact the gear, and once that happened, it's all over. I'll know for sure over the weekend. Shimming it would be next. I'm not taking the case apart again.

I mated the transaxle with the engine again, put it back on the subframe.

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found a spot to use for the bayfan temp sender - in this location I can pivot it in or out of the manifold heat to adjust fan onset if needed.

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Just a quick question do you install it complete like that into the engine bay?
On mine I had to leave intake alternator water pump off and reassemble in the car
 
Just a quick question do you install it complete like that into the engine bay?
On mine I had to leave intake alternator water pump off and reassemble in the car

I install it as shown - with only the alternator off. The water pump pulley is a problem - I have to lower the car with the motor pulled back at first, then once it's low enough, push the motor forward so the pulley will ride over the frame in that corner for the rest of the drop.

If I removed the torque mount arm, I could have left the alternator on as well - the first install I did that way, but the alt and torque arm scraped on the frame and crossmember going through the space.
 
Figured out the speed sensor issue - new sensor arrived & it's the same dimensions as the one I removed - inserting it into the trans cause it to hit the gear as with the original.

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It seemed like it needs about 1/8" spacing to clear the gear. I then realized that the washer on the securing bolt was pretty much that depth. I really couldn't recall how it was situated back when I took the trans apart in the Spring.

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- I had assumed the washer was to prevent the bolt head galling the mount point, but then it wouldn't need to be that deep. With it as shown, no more problem

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I guess I should have checked the parts diagram earlier on (#15 is the washer) :D

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Moving on, I got the RDX injector adaptor plugs installed - I had tried to swap just the terminal housing, however they don't fit the earlier terminals.

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That was an obvious one. NOT!
Who would have thought to put the washer under the sensor boss without the diagram or a really good memory of how it was when removed. That is an eye roller if I ever saw one.
 
Family visits over the weekend. Too cold to work outside currently. All I got done was some minor futzing with the wiring on the motor. Routed wiring & added connectors for the bay fan sender, the fuel pressure gauge sender, and the oil temp gauge sender

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To make this work I ordered an 1/8" NPT female - to - M10x1 male "Y"

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Got into the low 40's this afternoon, so I got the AC line fittings crimped & installed

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With this installed, I can put the drivetrain back in after work tomorrow, it's supposed to be high 40's :D

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Harness will end up routed like this:
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This is the AC beadlock hose crimp tool:

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Temps around 50ºF after work - so I got the drivetrain back in

Start with it pushed back and left side as far as possible

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So the water pump pulley will clear the frame

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Then push the motor forward & to the right, drop chassis a little, push again

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By time I got the subframe bolts aligned, it was almost dusk. Lifted the car back up & put it back on the jack stands for the night.


Worked on the rear wheel bearings after that.
 
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Busy day. Got the control arms on, the axles in (new boot clamps after the swap around, axle nuts torqued to 160ft/lbs & staked), the struts, swaybar, calipers, brake hoses & handbrake together. Brakes bled. Transaxle filled (2 quarts Torco MTF per Mfactory recommendation). Torque mount & frame bracket, Alternator & drive belt installed.

have to use an open-ended wranch of the trans fill plug, not clearance for a rachet wrench since I didn't cut the frame rail further back.

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New adjustable clamps - can be installed after the boot, much easier
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brakes

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ground strap attached to original frame pojnt and top of trans case

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AC line, handbrake cable, etc., routing - everything seems to line up nicely

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heater hose tucked up

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Detail of control arm dip & reinforcement

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After that, I lifted the car, removed the stands and ramps & got it moved to the garage. Thank goodness it's such a light car. Still managed to snag the spoiler lip on the right. Sounded like cracking fibreglass :(

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Gonna be tight working inside, but doable. Way too cold to be outside for prolonged periods now.

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Forgot to show slave cyl access - also I ground the corner off the casting to make it easier

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slides right into place

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hose routing
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Battery cable, throttle cable & pedal mod next, then finish the shifter & cable install. Then coolant tank & hoses. Still have to do the pedal box / clutch master install. Then wire everything - and make the exhaust :D
 
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Worked on installing the TB, intake hose and filter, fitted the header again to check fit after the modded runners, installed the fuel pressure sneder and on-engine gauge, fitted the heater and coolant tank hoses, worked on the AC lines from compressor to accumulator and low pressure switch housing.


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I have to figure something else out for the charcoal canister - it won't fit where I set it up with the engine harness and shifter cables. I don't want to rework them, so the cannister will need to move.
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I'll be drilling these and adding the weld-on R134a line fittings

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Didn't get much done after work today. Futzing with the AC lines- -the 'peanut" adaptors for the back of the compressor are wrong - for whatever reason I assumed the SD7 adaptors would work. The insert tube is the wrong size, and the offset of the bolt hole is slightly off. I may be able to modify them, by cutting an oring groove in the insert tube, and elongating the bolt hole in the 'peanut'.

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On my comprerssor, the bolt hole offset from the orifice centerline is 20mm as near as I can gauge. The orifices are .525" and .675". The compressor is actually a Diesel-Kiki KO (DKS15) CO 10421JC - Volvo used Zexel/DK for their 850 and x70 models at least though MY2000, which is what I originally bough this compressor for.

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after measuring those, I figured I'd get the throttle pedal arm cut short, so at least I could feel like I got something accomplished :D

About 1.75" height reduction, MWB says "reduce about 2 inches" in the notes.
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Dang, a lot to like in the narrative. Great pics, clear, well lit. Nice documentation of some really hard work.

Getting so close
 
Worked on the throttle cable - to -pedal arrangement. I'd been vasilating on how to address this, and decided that I really wanted to keep the original layout.

Drilled out the stock guide pin & sleeve to fit the M6 rod on the Venhill throttle cable. The rod length is close enough to the stock cable end. Flattened and drilled the rod to accept a hairpin.

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Making a support bracket for the cable sleeve to replace the long factory tube. Matching the offset of the cable tube from the tunnel, to make sure the cable aligns with the pedal arm.

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M5 rivnuts

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Been soaking the throttle pedal in old engine oil for a few days, to lube the shaft

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So, on Friday I only had a short time to look at this - fitting the throttle pedal with the cable/spring mechanism into the tunnel - no matter how I fiddled with it, it didn't seem that it would go through the aperature with the reduced lever height causing an issue with clearance of the pedal arm when pivoting/angling it to try to pass it through. Beyond that, there was no practical way I could see of reaching in the tunnel to situate the angle bracket that replaces the factory cable sleeve. I was considering drilling a 1.5" access hole in the side that would allow me to put a couple fingers in to hold the bracket whilst bolting it in place...

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....So I left it alone & futzed around with odds & ends. I had to come up with a method that would also work in reverse, should I ever need to replace the cable.

Yesterday I feel like I got a fair bit accomplished. I got the machined AC fittings back, so I installed them. Grooves cut to give .675" OD compression on the #10 fitting oring and .525" OD stretch on the #8 fitting oring. Drilled the 90º steel fittings and silver-soldered the R134a fittings to the 90º fittings. Rechecked the #8 & #10 line placement, crimped those fittings, and assembled all that on the car. Made the adapter harness to go from the compressor feed wire to the Fiat low pressure switch & back to the compressor. Tested it for continuity & installed.

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played around with alignment / offset of the hoses for a bit to get them as low as possible, and not touch anything that could be an issue due to normal engine movement. Had to buy a crow-feet set of wrenches to reach the #8 fitting on the low pressure switch housing.

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Then I realized I hadn't installed the cover hinges - which could have been an issue with the hoses already installed, however the right side studs are accessible from either the cabin opening or with an wobble extension from the bay.

With the hinges in, looks like it lays flat enough & not pressing on the AC hoses.

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With that (hopefully) finished, I moved on to the throttle cable/pedal install. I have to say, I really, really to not like working under the dash. My knees don't like it, my back doesn't like it, my eye glasses always manage to fog or move so I can't see clearly what I need to look at :( PITA to photograph also :D

Using a little template, I drilled the lower hole for the bracket. The upper hole is on of the spot weld holes from the original tube

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What I decided on, to resolve my dilemma of how to hold the bracket inside, was to weld a approx 4" piece of welding rod to it, that I could hold from above & push the bracket into aligment with the mount holes

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checking that it works, with no cable attached yet. Fiddly still, but works. Trick is to get one bolt in before loosing circulation in the fingers holding the wire :D

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All good. Then I pulled the cable sleeve back through the pedel pivot opening, put some shrink wrap ove the SS ferrule to keep it secured to the cable sheath. Then I desoldered the throttle cable barrel end,cleaned up the wire tip, and fed that from the pedal end through the bracket, and out the end by the throttle body

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Pushed the cable back into the tunnel, with the angle bracket

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secured the bracket in the tunnel, making sure the ferrule is located in the bracket - hard to photograph this part

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One clamp to secure the cable where the shifter moves around

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then came the bit I was dreading - getting the pedal pivot back through the tunnel - it actually went in really smoothly, pivoting the spring mechanism & pushing through much like this:

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....pulling the cable through in stages as I put the assembly in place to make sure it wasn't tangled/crimped. That went well (honestly, it did).

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Whew!

Then I moved on to the TB end

Fitted the cable around the bobbin, pulled it tight (with adjuster set somewhat centrally placed to allow for error), marked the cable, installed the barrel & soldered it back in place, cut the cable (Venhill VEN-UKCCBLACK )

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cleaned up the cable end, & installed it. Just have to adjust the bobbin spring preload, it's set too weak to snap the pedal back as is.

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I decided to get the battery cable in as well, to get as much of the on-my-knees-reaching up the tunnel/under the dash grunt work over & done with :D Went with a new aperature in the bulkhead, the stock one is too tight around a 0 gauge cable for safety

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used the old cable to pull the new one through the tunnel & out the new hole

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Now I can finish the tunnel paint, install the shifter & be done with that part (hopefully). I'll need to clean up the lower dash wiring mess and relocate the window switches later.

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next....
 
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Little things today. Got a spare drain plug & drilled/tapped it for the VDO 1/8 NPT oil temp sender. I couldn't locate a VDO M14x1.5 version

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clearly I didn't drill it dead center, but I'm not worried.
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wrapped up the battery/ frunk end of the cables - this new cable will feed the original fusebox, replacing the little brown wires. Lesser guage wires feed the ancillary fuses in the frunk

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couldn't do this without the crimp tool

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After that I installed new 10mm nitrile drain tubes for the battery tray & then futzed with the AC lines up front - removing all the butyl from the lines, etc.

Orifice tube adapter will go where receiver/drier lives. Will cut the existing forward #6 line & repalce the rear line that comes from the expansion valve.

Note: contrary to my pic, notched end has to attach to condenser/high side of line - that is the input - pressure drop occurs on other end of tube
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cleaned up the lines inside, in prep for removal & replacing the expansion valve with a pass through elbow, and new line going forward. I'm planning on moving the wiring to the otherside of the AC fittings, as Bertone laid it out, the fusepanel is awkard to drop without fiddling around with the harness tangling on the lines. I think it should work OK.

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After that, I got a little paint on the tunnel, where I had either stripped it or welded. Just going to plug the spot weld holes where I removed the original cable tube. I don't want or feel the need to weld them up.

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Got the gutted expansion valve fitted, the #6 hose from there to the orifice tube made, and the orifice tube housing fitted . Removed & cleaned the low side hose fitting to the evaporator & replaced the oring. Moved the wiring to the cabin side of the hoses.

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Need to reinstall the two pressure switches on the high side of the orifice
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battery back in place. Have to tidy up the high/low headlamp relays I added some years back - going to put them up on the right.

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Need to clean up all this mess, tidy up all the additions I've made over the years & remove stuff not needed anymore, and add the new feed from the battery. EDIT - Rodger's Cleanup

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