Performing Honda K24a3/AST5 6spd Conversion

Got the relay sockets wired, and function tested the controlled features. Trunk release now works from the remote as well as the override switch (still have both manual releases) . Rocker switch is for courtesy light override, so they don't stay on past the delay sequence when the doors are left ajar for work. Some revision to the relay wiring was needed as I of course mixed up a couple of the harness connections. All good now. Took awhile to get all the wires wedged back into the fuse panel support/cover - since they've been hanging out loose for a week or so they did not want to conform back into the compressed space between panel & cover.

Whats' not good is the mess of a positive feed to the aux power supply. I added a fused line to it, and the whole mess is just way to bulky & inflexible for ease of operation. It can be tucked up out of sight, I left it down to show just how ungainly it is. Seemed OK when everything was down, but hey, something was bond to go awry. It even interferes with the forward harness, as the rigid positive wires impede the forward harness looping up against the bulkhead as they should. I'll be revising the cable junction, and replacing the feed to the aux power junction with more flexible 8 or 10 AWG wiring, with less junctions.

All the loose wires no linger used will be tidied up for possible future use, I labelled the terminating end of each so I won't forget

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Still, getting close to being ready to drop the heater box & move on with that aspect.
 
A hair dryer helps to get the wires insulation to be a bit more conformal.

It is not a happy arrangement in the best of times.
 
Removed the extra feed for now. I'll address that when the new 9.5mm terminals arrive. It only needs to be a short run. I'm also thinking of adding a (nylon/plastic) securing loop to retain the cable junction to the underside of the panel cover - pretty much where I'm holding it in this pic would be perfect.

EDIT - maybe I'll cut back the new power cable & have the junction follow the rear cabin harness path - I think that would be a neater solution. Then run the aux power feed along the loom currently traveling to the right below the box. That depends on how 'relaxed' a fit I can get on the wires as they go into the aux power junction - to allow enough slack for when the box is lowered & pulled rearward.

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Had to rearrange the looms some more to get a better loop when it's shoved up & back. The expansion valve is right in the path of the rear cabin harness push back - since I am only using that as an elbow, I think I will cut off the chamber so it is literally a plain elbow. That will allow the harness to push back with less finagling.

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The thermocouple has already been removed - just need to removed (as seal off if needed) the (diaphragm?) chamber - pic from a year or so ago, with AC tray out of the way

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Could you put a power junction on top of the tunnel under the HVAC box? It isn’t something that needs to be accessed with regularity.

Also could it run behind the AC lines along the face of the firewall?

Removed the extra feed for now. I'll address that when the new 9.5mm terminals arrive. It only needs to be a short run. I'm also thinking of adding a (nylon/plastic) securing loop to retain the cable junction to the underside of the panel cover - pretty much where I'm holding it in this pic would be perfect.

EDIT - maybe I'll cut back the new power cable & have the junction follow the rear cabin harness path - I think that would be a neater solution. Then run the aux power feed along the loom currently traveling to the right below the box. That depends on how 'relaxed' a fit I can get on the wires as they go into the aux power junction - to allow enough slack for when the box is lowered & pulled rearward.

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Had to rearrange the looms some more to get a better loop when it's shoved up & back. The expansion valve is right in the path of the rear cabin harness push back - since I am only using that as an elbow, I think I will cut off the chamber so it is literally a plain elbow. That will allow the harness to push back with less finagling.

View attachment 40921

The thermocouple has already been removed - just need to removed (as seal off if needed) the (diaphragm?) chamber - pic from a year or so ago, with AC tray out of the way

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Could you put a power junction on top of the tunnel under the HVAC box? It isn’t something that needs to be accessed with regularity.

Also could it run behind the AC lines along the face of the firewall?

The problem is the red & brown existing feeds that are spliced into it - are too short to go back there - I'd then have to have an additional junction to connect those, so then back to square one....

I'll play around with that though, when I drop it all again
 
The problem is the red & brown existing feeds that are spliced into it - are too short to go back there - I'd then have to have an additional junction to connect those, so then back to square one....

I'll play around with that though, when I drop it all again
The other choice I have been thinking of is going upward under or over the HVAC hose going to the right vent. This would place it behind the glove box and accessible if it is ever needed.
 
The other choice I have been thinking of is going upward under or over the HVAC hose going to the right vent. This would place it behind the glove box and accessible if it is ever needed.

That would be a safe place - however it would mean adding significant length to the relay panel feeds.

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Repinned the headlamp side of the stalk with another TS090 10 pole setup - much better than the old terminals. I was initially concerned about the new terminal size -- however these actually have a larger contact area than the twinkie factory terminals, and the housing is not larger than the 6 pole spade/Faston

- old pic taken during brake MC work showing original 87 connectors:

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1/0 butt splices and 9.5mm terminals arrived so I was able to wire the aux power junction today, and realign the main feed. I had to add an extra loop to the panel side of the splice - otherwise the 1/0 crimp would not work. It'll be in place should I ever need extra (30) power supply

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Still have to open the forward harness & remove the headlamp motors wires I removed from the relay panel EDIT - thinking I should keep them as spare pass-through wires, and bring the other ends (that terminate in the headlamp pod area) back into the Frunk for future use.

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The cabin harness & power feed will be higher up once the heater core is done - right now the bypass/hose arrangement is pushing everything lower than it will sit when all is done. Originally, all that wiring was routed behind the AC lines, however that precluded pulling the relay/fusepanel into the footwell area to any meaningful degree for servicing

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VW delay relay location - Volvo relay in there for now Relay Mod Thread

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New switch wiring

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removed the heater box - directions say drop fuse box & move it aside :D

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hung up on the wiring... the heater valve bracket snags the cabin harness & power cables I added

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finally out - thankfully no damage to wiring loom from the heater valve bracket - it was wedged against the loom as I worked it back & forth shifting the angle of the box to get it out

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I'l be tidying up the cables to make sure they are all behind the heater box & hoses

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I broke the pivot finagling the box out, the top flap is seized like Rodger's was, and so the back flap wouldn't close when I pushed hard on it

Referencing LarryC's awesome heater box thread for details


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lubed the top hinge - hopefully it will free up properly

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Cut off the entire heater valve bracket - I don't need any of that mess, with my bay mounted (Volvo) heater valve install. Should make reinstall easier.

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I managed to unscrew the valve from that bracket which was the devils own work with it in situ. When the valve goes back in it will be free floating on the hoses and will have no relationship to that bracket.

A really stupid question. Is it possible to remove the box (in pieces) and leave the AC matrix hanging in space? I am hoping not to have to recharge the system (assuming it has anything in it on my 87). AC isn’t or hasn’t been my forte to this point.
 
I managed to unscrew the valve from that bracket which was the devils own work with it in situ. When the valve goes back in it will be free floating on the hoses and will have no relationship to that bracket.

A really stupid question. Is it possible to remove the box (in pieces) and leave the AC matrix hanging in space? I am hoping not to have to recharge the system (assuming it has anything in it on my 87). AC isn’t or hasn’t been my forte to this point.

I can't imagine accessing the htr valve retaining screws in situ - mine required clamping in a vice to break free.

The directions for heater core replacement say only to drop the lower casing, which would be much easier than taking the box out. I wanted to service the whole thing so I didn't bother trying to do that. I would expect your fresh air flap is also seized, so leaving the top section, would not be ideal, never mind that the seals & goop in there will make that very difficult in situ.
 
Repinned the headlamp side of the stalk with another TS090 10 pole setup - much better than the old terminals. I was initially concerned about the new terminal size -- however these actually have a larger contact area than the twinkie factory terminals, and the housing is not larger than the 6 pole spade/Faston

- old pic taken during brake MC work showing original 87 connectors:

IMG-20200222-115040.jpg


View attachment 41042

1/0 butt splices and 9.5mm terminals arrived so I was able to wire the aux power junction today, and realign the main feed. I had to add an extra loop to the panel side of the splice - otherwise the 1/0 crimp would not work. It'll be in place should I ever need extra (30) power supply

View attachment 41043

Still have to open the forward harness & remove the headlamp motors wires I removed from the relay panel EDIT - thinking I should keep them as spare pass-through wires, and bring the other ends (that terminate in the headlamp pod area) back into the Frunk for future use.

View attachment 41044

The cabin harness & power feed will be higher up once the heater core is done - right now the bypass/hose arrangement is pushing everything lower than it will sit when all is done. Originally, all that wiring was routed behind the AC lines, however that precluded pulling the relay/fusepanel into the footwell area to any meaningful degree for servicing

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VW delay relay location - Volvo relay in there for now

View attachment 41045
Who makes that speaker? Self-enclosed kicker, or mounted on wood?
 
Who makes that speaker? Self-enclosed kicker, or mounted on wood?

These? They are the front door speaker/tweeter from the Volvo S40 I stripped for the AWD conversion on my C30 - that model came with the Premium sound system (Bose speakers, I presume) - includes another tweeter that I added to the top of the dash. These have a plastic casing around then that would normally seal against the inner door skin - with a hole for just the magnet/ air gap. It has been suggested I should cut the hole behind them in the inner fender. I'm still considering that.

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Tidied up all the wiring behind the heater box. Should be all good once I get the HVAC unit restored & back in

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finished the delay relay wiring -all good now

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Dismantled the HVAC box - full of pine needles & debris from the frozen fresh air flap

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Cleaned all the casings - several stress cracks needed repair, resulting (I presume) from the seized flap exerting undue stress on the upper casing

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Had to make a new seal for this

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Cleaned all the pine needles out of the Evaporator

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Modded another expansion valve to remove the expansion component - drilled it out & silver-soldered the holes in the end after the cap was removed. This is to make it as compact as possible, so the wiring harness doesn't snag on it as it has.

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Acid treated the two flaps, painted & applied seals.

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hinge repair. ABS cement to join additional support outside of the broken pivot seat. I have no reason to ever remove it, so no reason to make it 'unclippable'

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cracks around the evaporator mount - this point had no washer beneath the securing screw. I will reinforce the top side of the housing

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Made a new evaporator/ housing seal


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Bunch off little things today - made a new neoprene (1/8") seal for the center vents

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using screws from an old Volvo - torx w/integrated washers - less fiddly
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Checked the motor / brushes - plenty of brush left, and no scoring/wear to speak of on the armature. Motor is quiet when run.

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Hard to photograph, but the original tie wrap that held the wires was stretched and the negative sheath was rubbing the inside of the wheel. The two terminals are un-insulated, so I added some heat-shrink - without it, if you pull a tie wrap tightly, the (+) terminal is close to touching the bridge beneath it. Still need to clean it up/ spray with electrical contact cleaner

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Removed the old seal from the body opening

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cleaning the residual glue off the opening was probably the worst part of this job, for me, anyway - had to contort myself to get under there - still some more to go, and a little surface rust repair.

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applied the new seal to the heater box - I had made it from 1/4" foam, however there are thick washers that space the box down away from the opening by about 1/4" - so I added another layer of 1/8" foam to bring it to 3/8". That should give some compression to the seal when installed

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I took the pipes off the heater core I got from MWB a year ago to change the seals before installing. The core doesn't look great - pretty heavy scaling in there. Anyone had any success with vinegar or other mild agent to de-scale the core?

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You seem to have a fair amount of leftover red paint.

They will take points off for the non standard color at the concours

No really they will

I believe you. Do I care? I think that would be the least of my issues :D

This is actually a deep red rustoleum enamel - I could have used the ol' standby Sunrise Red, but I had left that out in the garage when I started on this, and didn't feel like waiting for the paint to get up to room temp. The Passion Red I used for the bodywork, I do have another quart - but that has to be spray painted.
 
I've used LimeAway on crusty radiators before. Seemed to work OK. I had to let it sit for a couple of days though.
 
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