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In-Car Headswap, Semi How-To. K24/20 Frank.

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46K views 26 replies 15 participants last post by  Mixwell  
#1 ·
I guess I should first give some insight to what is going on here. I originally swapped a bone stock K24A1 into my hatch to get it moving, while I was very impressed with it I kept trying to kid myself that I wouldn't do a headswap. I was wrong, and less than a week after installing the K24A1 I bought a low mile 2002 RSX-S K20A2 head. This is somewhat of a How-To on doing a headswap with the motor still in the car, to my knowledge nobody has done one of these yet.

Please keep in mind I took very very few pictures as I do not like to get my camera messy and stop working to take pics.

Tools needed:
-Full socket set (Deep/Shallow 1/2" 3/8" 1/4")
-Ratchets (Duh)
-Crank pulley removal tool
-Torque wrenches (one for smaller settings, one for large)
-Full screwdriver set (prying stuff, hose clamps, etc)
-Several ratchet extensions
-Scrapers (Old gasket material)
-Hondabond HT (Honda genuine RTV, I highly recommend this stuff)
-Random pliers/cutters
-Wrenches 8-19mm (Ratcheting and normal, very helpful)
-Large 1/2" breaker bar (to hold crank pulley removal tool)
-Metric allen keys

Time required: ~10 hours

The tools really aren't the most important part, the most important thing is insane amounts of patience. It takes time to get to some of the bolts but it's not inherently hard because the motor is still in the car.

Okay, so..onto the actual process of removing the head while it's in the car.

Step1: Jack up vehicle on four jack stands. Disconnect the battery, Drain Coolant and Oil from engine, this is self explanatory. Remove the passenger front wheel.

Step2: Disconnect all of the sensors connected to the head and any of the harness that may get in the way, this includes - Crank sensor, Oil pressure sensor, VTEC sensor, VTC spool solenoid, Injectors, Coilpacks, Cam position sensors, etc. Disconnect the front coolant port from the head if you are able to do so, this makes life very easy.

Step3: Remove valvecover, intake manifold, header and passenger side engine mount. Support the engine using a jack and some wood on the oilpan, or in my case on the water pump housing as I did an RSX-S oil pump at the same time. At this time remove the crank pulley using the holding tool and a big honking ratchet. I use my 26" snap on 1/2" ratchet and a 18" 1/2" extension. I usually brace the pulley holding tool against the axle or front LCA with a breaker bar.

Step4: THIS IS THE HARD PART Removing the timing chain cover: you cannot pull out the bottom bolt of the passenger side mount that is connected to the chain case while it's still in the car, it is impossible unless you can somehow remove the Hasport frame rail mount. I tried doing that to no avail. What you must do is remove the cams/timing chain tensioner/rocker assembly first and then take EVERY 10mm bolt out of the chain case and then slide the entire assembly up and out of the car while the passenger side mount that is connected to the chain case comes with it. I will warn you, it is a ROYAL pain in the ass if you don't know what you're doing. It CAN be done.

Step5: Loosen the head bolts, take off the back chain guide arm and pull off the head, make sure EVERYTHING is off of the head before you pull it. Pull the head and inspect the cylinders to make sure EVERYTHING is clean. Clean off both the head/block mating surfaces.

Once you reach this point everything is the reverse of removal, Minus installing the chain case. Installing the chain case MUST be done from the bottom as you cannot install it with the cams/rocker assembly not installed. I had to remove the oil pan to do an RSX-S oil pump at the same time so this was no huge deal, it DOES require two people to line up perfectly and not hit anything. You must remove the oil pan to do it.

Once again, I am assuming everyone knows the proper procedure for checking the deck of the block and head for warpage. Mine were fine, I also assume you follow all torque specs and tightening procedures and know how to time a K-series motor. This is really meant to show that the head swap CAN be done with the motor still in the car.

There you have it, the only pictures I snapped are after I installed my ARP headstuds and OEM Honda CRV 87mm Headgasket.

Image


Image


Fancy huh?

Notes:
- RSX-S Oil pump is a DIRECT bolt up to the K24A1, no modifications. All you need to do is Hondabond the bottom of the pump mating surface and tighten it all down. You can re-use the two 12mm bolts from the stock pump and you need to find a 1.5" 10mm bolt for the third. The windage tray is also a direct bolt up, hardware is used from the old stock tray.

There you have it, if you have any questions feel free to ask me here or via PM/AIM.

-Froth
 
#2 ·
:wow: Good job right there:wow:

Question though.. I see you indicated that the est. time for the job is 10 hours. Do you think you could of taken out the engine, change the head and oil pump & put it back in in less or the same amount of time?

I know the engine can be taken out in 1hr or less and installation is the same... Are you saying that changing the head and oil pump is an approximate 7-8 hour job?
 
#3 ·
Very well done. Thank you for posting this.

1320 is asking a good question.. which one would be faster, assuming that you had access to an engine hoist.. which is not something that everyone has in their garage.

In order to remove the motor, you generally have to

-loosen axles nuts
-drain tranny fluid
-remove axles
-disconnect fuel lines
-disconnect header or remove header
-disconnect shifter cables
-disconnect slave cylinder still attached to the clutch line
-disconnect harness and charging harness
-disconnect and drain radiator hoses
-disconnect heater hoses
-disconnect grounding wires

As motor is getting hoisted, you get the bolts out from the mounts and the motor is out...

and now taking off the chain cover and head are much easier... but installing the type s oil pump... is going to kick your ass... lol Unless you can hoist the motor up with the tranny and work on the oil pan while the motor is suspended in the air... pretty scary if you ask me... so you better lay the motor on its side.. which means you have to also drain the oil... but it is easier to access.

But if you don;t have an engine hoist, you have no choice but to give it a shot..

I have no power tools, but in about 4 hours, I can take the motor out, change the clutch, go in the house check my email... and put it back in the car and have the car running...

Your way has some advantages for sure and I am glad you got it done right but the limited space between the chain cover and the frame rail is enough to make someone go crazy.

Did you have access to an engine hoist, or you just wanted to do it with the motor in the car? I can imagine torquing the head on the block while in the car must have been way better as well as leaving the axles and water hoses connected... You can also make it into a week project where you work a little bit every day... which is way better than having the motor out of the car because you need to have the hoist around to place the motor back in... etc...
 
#4 ·
I agree with that Nikos.. There are pros and cons to doing it either way. Taking out the engine IMO is the most efficient cause it give you full acces to everything.. If your planning to do a head swap, the coolant and the oil has to be drained regardless.

The good thing about it is that everything else stays put (shifter cables, axles and suspension, harness, and a few other things.. However with these swaps, those are really not much to disconnect.. All of what I mentioned is about to minutes tops to disconnect. Leaving the head on the car seems to be a method of convenience and means that you are really in no rush to get it back up and running, you just dont want to take out the motor and/or you dont have access to a hoist and thats not a problem.

The bad thing is that its time consuming due to limited access. All the 10mm bolts and then the arm and guide and sensor removal...Not to sure how much of a pain that is.

Ive taken out my engine before in about 50-60 min(before all the turbo stuff was there) without a hoist and ive also taken out the tranny while the engine was in the car still and it took the same time but I have a Crx.... Not much room there..

If you have access to a hoist and power tools though removal of the engine may be a more efficient way to go though.... I guess what attributed to the fact of it taking so long was the fact that you didnt use any power tools..

Im still happy to know that it can be done though...:up: Glad I seen this.
 
#5 ·
I work in a shop, the only power tool I ever use is my 3/8" and 1/2" impact guns. I never use air ratchet, ever. I can attribute so many stripped bolt heads/nuts etc to air ratchets that I'd rather take the extra 5 seconds to use my hands. I have a compressor at home, it rarely gets turned on.

I have an engine hoist, honestly...this is easier. 10 hours was a TOTAL time meaning smoke breaks, beer breaks, printing out torque specs/tightening patterns and random friends coming over, etc. If I had to do it again I could do it in about 4 hours. It's actually easier this way IMO.

Every single bolt on the chain case cover can be reached from the bottom of the vehicle, I used my small snap-on 1/4" soft grip ratchet and 10mm socket for every single one of them. It's not very hard at all, the bottom is the easiest access point for all of them minus the top two.

-Froth
 
#8 ·
sure it can be done, but I wouldn't want to risk the timing screw up.
ask nikos he knows best. :)

depending on the guys experience..:rolleyes: also might need two people!
 
#10 ·
Very nice writeup! Nikos, can you make this into a sticky. Froth, can you post up the necessary torque specs for the bolts that you had to tighten down or post the manual pages you referred to for this.
 
#11 ·
Here, this should help.

I HIGHLY advise the use of ARP headstuds, anything worth doing is worth doing right. ARP headstud torque = 70lbft using their moly lube, this is the tightening sequence for the headstuds. I go over it three times.
Image


Cam cap torque sequence/specs. Again, I go over it three times.
Image


Crank pulley bolt = 181lbft

Everything else I tightened down by hand, I'm used to it and have never had an issue. Essential items like the Head/Crank Pulley/Cam Caps however MUST be torqued. Refer to your specific mounts torque specs for re-installing those items.

-Froth
 
#14 ·
Step4: THIS IS THE HARD PART Removing the timing chain cover: you cannot pull out the bottom bolt of the passenger side mount that is connected to the chain case while it's still in the car, it is impossible unless you can somehow remove the Hasport frame rail mount.
-Froth
Just started my in-car head removal today. I got to the part where the pass. mount bottom bolt got stuck in the tight spot. I tried to move the hasport frame rail mount forward towards the headlights for more room. Theres a piece of metal under the frame rail that stops that idea. When i get a chance i will drill the welds out that is holding the metal plate and i should always be able to slide the hasport frame rail mount forward. As for getting the last bolt on the side mount out easier you can jack up the motor for just enough room while you wiggle that bolt out. But this is for a k20 in an eg i dont know if the extra 19mm deck height on the k24s make a big deal.
 
#22 ·
Ya even in my ek with a k24 u have no room to remove the mount , the hassport frame rail mount must be removed to get out the mount bolted to the timing chain cover.

Im all done I just need to rig something up to remove the crank pulley cause I don't have the special tool .

Also any cam /rocker arm removal tips you guys have , thanks for your help!
 
#16 ·
Well I hope I can do this in my ek , I am starting today , I wish I had a hoist cause I could use a new clutch at the same time ,and pulling the motor for the head and clutch would make sense ,but hopefully like froth mentioned its not too bad ,
 
#17 ·
I did both in the car, Headswap isn't bad and the Clutch isn't too bad either. The only part that sucks with doing the clutch in the car is if you have a P/S rack as it gets in the way of taking the trans out from the bottom. All-in-All...I'd still choose to do both things with the motor in the car.

-Froth
 
#24 ·
Removing the timing chain cover: you cannot pull out the bottom bolt of the passenger side mount that is connected to the chain case while it's still in the car, it is impossible unless you can somehow remove the Hasport frame rail mount. I tried doing that to no avail. What you must do is remove the cams/timing chain tensioner/rocker assembly first and then take EVERY 10mm bolt out of the chain case and then slide the entire assembly up and out of the car while the passenger side mount that is connected to the chain case comes with it.

Just an update on this..

It is very possible to remove the timing chain cover while the motor is in the car without removing the Hasport rail mount. I did it last night, took me around 10 minutes.

With the motor ready to run in the car... you

-disconnect battery
-use a jack with a piece of wood to support the oil pan-tranny area
-remove the 2 bolts that connect the hasport mount with the CRV/k20 bracket

Image


-remove the hasport mount fromt the bracket.

Image


Now there is enough room to take out 2 of the 3 bolts that hold the CRV/k20 mount.

The top 2 bolts can come out now..

Image


The 3rd lower bolt cannot come out because it is hitting the bracket...

Just use the jack and slowly jack the motor up till the bolt has enough room to get out. The rear mount and passenger mount , along with the axles, radiator hoses have enough slack to do this. Just make sure your intake piping is not attached to something. As you jack the motor up to clear the bolt if the motor is not moving up something is holding it back.. most likely a tight ground cable or an intake manifold pipe that is bolted on the chassis...

Once the bolt is out you can jack the motor back to normal level again...

Next step is to remove the crank pulley using a crank pulley holder or impact gun...

Once the crank pulley is off, time to take out the 10mm bolts that hold the chain cover, most of them can be reached with a 10mm socket and 1/4 wrench. Once they are all out, remove the chain cover...

From then on, you can remove the head, change cams, replace gaskets, even replace pistons and rods if you are that good...
 
#26 ·
One thing I've noticed now, I have the new Generation of the Hasport EGK1 mounts...There's a hole in the middle of the upper section, the bolt slides right through it. Not sure if it was done on purpose or not but it can be done fairly easily now.

-Froth