This document contains notes from rebuilding the cylinder head on my 2001 Kia Rio.

Documentation for this car is sparse. Haynes manual does not carry the ’01 Kia Rio. I

bought the Kia Spectra manual, but it was far too generic and useless. Chiltons does carry

the ’01 Rio, but it is basically a copy of what is freely available on the kiatechinfo website.

So I had to do a lot of searching online and trial and error.

What happened: The car overheated once about two years ago due to a failed radiator

fan. Since then it has been having a number of problems. It was hard to start if it has

been sitting for a few days (probably due to coolant dripping into the cylinders). Then it

overheated again due to a radiator leak. The leak probably happened due to the

compressed fuel/air mixture leaking into the coolant system. After replacing the radiator,

it overheated almost immediately, and this time I could clearly see bubbles coming out of

the coolant overflow bottle. It also smelled of fuel. It was clear that the cylinder head was

leaking.

It took 2 months to do this, mostly spent waiting for parts or tools to arrive. After

completing this work, the car was running like it was when it was brand new, absolutely

quiet and smooth. It was a satisfying end, and I learned a lot of things about engines

during the process.

Photo: Engine before starting the work

I should have removed the radiator, windshield washer reservoir and battery sooner

instead of waiting for when they had to be removed. The extra room made the work

so much easier.

I used Ziploc bags to organize the nuts and bolts and also to prevent losing them. I also

took lots of photos before things were dismantled and wires removed, so that I can

reconnect them again without too much trouble.

The intake manifold was not easy to remove. In addition to the manifold bolt, the

assembly is also held by two extra bolts on a lower horizontal support plate bolted to

the frame under the engine. These bolts are not visible from the top, and it was not

easy to figure out what was preventing the manifold from moving.

Photo: After removing the valve cover gasket and exhaust manifold

Removing the water pump pulley was very tough due to the tight space. After buying

and returning all kinds of pulley holding tools, I used a strap wrench to hold the pulley.

This works, but it is still difficult because there is not much space even for a strap

wrench. The easiest method by far is to loosen the bolts while the drive belt is still on

and under tension (duh, isn’t this is the ideal strap wrench?). During installation, just

hand tighten the pulley bolts, then install and tension the belts, and then finally

tighten the pulley bolts. I wish I had thought of this method sooner.

I bought the the Sunex long-arm ratcheting combination wrench (saw someone using

it on youtube -

https://www.youtube.com/watch?v=ovd5A17_Ovc&index=69&list=UUT5dv3iwFuy04

1dbWPB6skg). Despite its high price, it made reaching bolts in difficult areas much

easier.

Power steering pump and alternator will require the entire tension adjusting plate to

be removed. Just loosening the adjusting nut and the mounting bolt did not allow it to

slide easily in the slot. This is probably because the brackets had a lot of grime

buildup.

The head bolts were removed with 12mm 12-point deep sockets. These sockets can

be bought individually at Lowes instead of buying a whole set from Auto stores. The

removal pattern is important, but I didn’t pay attention to it since I knew the cylinder

head was warped and had to be machined anyway. Lifting the head off the engine was

easier than I had expected. Once all the bolts were off, the cylinder head separated

from the block all by itself, and I was able to lift it out of the way. It probably weighed

about 30 pounds.

Photo: After lifting the cylinder head off the engine block

Photo: Cylinder head on the floor.

I measured a warp of 0.010” on the cylinder head and 0.002” on the deck. The deck

was within spec, but the head was significantly warped. So I took the cylinder head to

a machine shop for cleaning, pressure testing and machining. It came back totally

clean and dry. Cost was $120.

Photo: Cleaned cylinder head after service at the machine shop

The deck was sprayed with “Aircraft Remover” and scraped with a blade to remove all

traces of the old gasket. The same was done with the intake manifold. The pistons

were also sprayed with the same stuff and wiped off.

Photo: Cleaned deck, pistons and intake manifold

The head gasket set I bought also came with valve guide seals. Even though the

machine shop did not find any leaks in the valves, I went ahead and replaced these

seals anyway. Removal of the valves requires a valve compression tool. The generic

kind won’t work because the Kia valves are recessed inside a hole with very little

space around it. The tool I bought is a large C-clamp with socket attachments. These

sockets have side openings to access the valve retaining clips. Later I discovered that

the Lisle valve keeper tool is much better than the C-clamp tool. Removal of the valve

stem seals also require a special tool. Pulling it with pliers did not work, and even with

the special tool it took a lot of wrestling to get the seals off.

Photo: Head gasket set

Photo: C-clamp style valve compression tool

Photo: Valve stem seal removal tool

Photo: Exhaust valves

The exhaust valves had a lot of white buildup. I tried cleaning them with a brass wire

brush but the buildup was too stubborn. So I sent all of the valves back to the machine

shop for cleaning and refacing. Cost was just $2 per valve, and got them back the

same day. They used a heavy duty steel wire-brush to clean the valves, and a precision

grinder to polish the sealing face along the edges. No wonder my brass wires did not

work. Most of the advice on the internet seems to recommend against steel and to

use brass. But these valves are made of hardened steel, so it is unlikely to get

damaged from a steel brush.

Photo: Valves before cleaning and refacing

Photo: Valves after cleaning and refacing

The valve stems should be fully lubricated with oil before inserting them into the

holes. The next step was to lap the valve seats. This requires a valve lapping tool and

lapping compound. When reading about it, this process sounds a bit mysterious, but it

is really simple. The lapping sound changes from a low-pitch grinding noise to a high-

pitched squeaky sound, which is when we lift the valve and repeat the process a few

times. Then thoroughly wipe the area of all traces of the lapping compound. The idea

behind lapping is to make the contact areas smooth but lightly grooved concentrically

so that they can seal well.

Photo: Valves lapping tool

I was unable to install the springs and keepers using the C-clamp valve compression

tool. There just wasn’t enough room sideways through the sockets to reach down to

the valve stem. After searching around, I bought the “Lisle valve keeper and remover

tool”. I should have bought this the first time. This works for removal as well as

installation, but it does require a lot of force to get the keepers to snap back in place.

A youtube video (https://www.youtube.com/watch?v=VIwmf0nhljU) made it look

really simple, but I had to struggle a great deal. Some recommended using a hammer.

After trying it, I didn’t like the idea of banging a hammer to compress a spring (not to

mention it didn’t work most of the time). So I used a wooden bar across the handle to

give it extra leverage to push down on it. That made the process quite a bit easier.

Photo: Lisle valve keeper insertion/removal tool

Photo: Wooden bar for the pushing against the keeper-installation tool

Photo: After installing the valve springs and keepers

The HLA (Hydraulic Lash Adjuster) are the silvery cylindrical buckets that slide through

the holes and push on the valve stems. These are most easily inserted and removed

with a magnetic pickup tool. I had assumed these were just cylindrical blocks of metal

and hadn’t given them much thought, until I installed the camshafts and discovered to

my dismay that all the valves remained open by random amounts with no relationship

to the cam lobes. After reading about it, I found out that the HLAs are not just pieces

of cylindrical blocks, but are miniature oil reservoirs. They are designed to smoothly

ride on the camshaft lobes to keep the valves continuously in contact with the

camshaft. If there is even a small gap, it would result in a hammering action that could

cause the camshaft to erode, and also make the engine noisier. The HLAs contain a

spring-loaded piston and a check valve to hold pressurized oil inside. During

installation they should contain air instead of oil. This makes them compressible when

pushed by hand. When the cam starts turning, the air in the pistons will be driven out

and oil will be sucked in. As it fills with oil, the check valve locks in the oil. Since oil is

much less compressible than air, the HLAs become much stiffer. This makes the piston

push against the valve stem instead of compressing. It is a very clever design because

the HLA automatically adjusts its thickness to compensate for the play between the

cam lobes and the valve stems. Without these HLAs, we would need precisely

machined spacers, and that pieces may have to be re-machined periodically to adjust

for changes in the cam lobes. The only problem with these HLA’s is that whenever the

camshaft is removed, the pistons inside the HLAs will automatically inflate and will fill

with oil from the surrounding area. Once they expand, they cannot be put back in

service without draining the oil out first. Doing so might cause valve to malfunction.

The Kia is an interference engine (meaning the pistons can contact the valves if the

valves are open when the piston is at the top dead center) so this is an important

consideration.

All of my HLAs were full of oil and were solid as a rock. Without understanding how

these things worked, I tried compressing them on a bench vice attempting to squeeze

the oil out. But they didn’t budge. I took it to my machinist to ask for advice. He tried

compressing them as well and said I may be out of luck and may have to buy new

ones. At about $15 a piece, 16 pieces could get pretty expensive. That is getting close

to the price of a new cylinder head. Then I found a youtube video

(https://www.youtube.com/watch?v=HT71uhnNYjg) where they were pulling the

piston out with pliers. Another youtube

(https://www.youtube.com/watch?v=ySf0r8GGMOY) showed smacking it on a hard

surface several times to pop the pistons out. Both techniques worked, but pulling

them out worked much better for me. The trick is to use a long-nose locking vice grips.

Regular pliers, even needle nose pliers didn’t work. I mounted the HLA on a bench vice

(with towels) and locked the vice grip and pulled while turning. It slips a number of

times, but eventually the piston pops out. It’s a matter of patience and technique.

Once it pops, oil pours out that looks like black tar. This is oil that has been locked in

there for ten years or more. Once I got going, it took less than five minutes to

disassemble all the other ones.

The internal parts of the HLA’s piston assembly can be pried apart easily. It contains

the piston itself, a check valve and a small spring. The check valve can also be

disassembled quite easily by prying out the frame that holds a steel ball inside a hole. I

cleaned these pieces in Brakeleen, oiled them and reinserted them back into the HLA

body. The parts should be lubricated with oil, but the piston cavity should not be filled

with too much oil – otherwise it won’t compress. The HLAs initially need to be

compressible in order for them to inflate to their proper heights.

Photo: Removing the piston assembly out of the HLA body

Photo: After removing the piston assembly from the HLA body

Photo: Dismantling the piston

Photo: HLA body, piston, spring and check valve

Photo: After installing the HLAs

One camshaft is a bit longer and has an extra piece at the end for triggering the

camshaft position sensor. It is also best to check that this tail piece is securely screwed

in before putting the camshaft in. I also replaced the front oil seals, which came in the

head gasket seal kit.

Photo: Oiled cams in place

Before installing the cam carrier, I applied Ultra Grey sealant in a bead along the path

shown on the Kiatechinfo website. The diagram is very difficult to follow, and I had to

guess which lines were supposed to be the sealant. The sealant spills out a bit during

tightening, and I wasn’t sure how much will seep into the oil pathways. Hopefully not

much. The tightening torque calls for 10 ft-lb, but my wrench only goes down to 15 ft-

lb, so I just hand tightened it.

Photo: Cam carrier

This is also a good time to replace the timing belt. This requires the removal of the

crankshaft pulley, crankshaft bolt and the timing belt guide plate. The crankshaft

pulley bolts were removed by holding the crankshaft center bolt and turning the

pulley bolts. But prying the pulley out was a lot more difficult. My two-jaw puller has a

tapered tip, but there is no hole on the crankshaft bolt for the tip to center on. But I

wrestled with it and managed to pull the pulley a just little bit. Then I inserted a prybar

behind the pulley to pry it out. However, this ruined the plastic timing belt cover. A

new cover had to be bought. I later discovered that I didn’t really have to remove the

pulley mounting bolts – I could have removed the crankshaft bolt which would have

allowed the guide plate and the pulley to be taken out together.

Removing the crankshaft bolt was even tougher, even with an air and electric impact

wrench. It would not budge even after soaking it in WD-40 for days. With much

trepidation, I used the brute force method – lean a breaker bar (with a pipe extension)

on the concrete floor secured to the vehicle with a clamp, and then bump the starter.

The bolt came off surprisingly easily. Loosening direction is counter-clockwise (normal

direction). I later discovered that the process could have been a lot simpler if I had

removed the crankshaft position sensor and inserted a screwdriver to jam the

flywheel.

Photo: After removing the crankshaft bolt

Photo: Crankshaft bolt

Photo: Timing belt guide plate

Photo: Timing belt sprocket

This was also a good time to replace the water pump because it is a cheap item. But

the water pump turned out to be one of the most difficult tasks. It required the

removal of both timing belt rollers, and four mounting bolts. These bolts are all hidden

and hard to locate due to the tight space. It would have been impossible to identify

these bolts without comparing against the new water pump.

Before the water pump could be taken out of the vehicle, the water inlet pipe had to

be disconnected. But its bolts were hidden behind the power steering pump. So that

had to be removed. But it’s long mounting bolt could not be pulled out without

interfering with the nearby brake lines. So the brake lines’ brackets also had to be

removed at two locations to allow them to be moved a bit. Then the power steering

pump was removed and moved out of the way without removing any of its hoses.

Even with the power steering pump out of the way, the lower bolt on the water inlet

connection was still blocked by a bunch of things – the oil dip tube, the power steering

pump’s mounting bracket and the AC compressor. Removing the dip tube and the

power steering pump’s mounting bracket would have given sufficient access, but the

dip tube would not budge, and also one of the bolts on the steering pump bracket had

been stripped by someone before. This is probably because the spacer used for the

steering pump was blocking one of those bolts. Unlike most spacers, this one is

inserted into the bolt hole, so it needs to be tapped out. The last mechanic who

worked on this probably could not figure out how to get this spacer out so he must

have tried to unscrew the bolt behind it without adequate access and ended up

stripping it.

The alternative path was to remove the AC compressor and its mounting bracket. The

compressor is mounted to the bracket with four very long bolts. These were easy to

remove. The bracket is held to the engine block with 6 bolts, which were also fairly

easy to remove. Then the AC compressor was moved out of the way with all is hoses

still connected. This allowed a limited access to the water pump’s inlet bolts.

After removing the old water pump, I replaced it with a new pump. The mating

surfaces were cleaned. The manual says not to use any sealant, but a tiny bit of water

pump sealant helps to hold the gasket during mounting, especially for this case since

the water pump is in such a difficult position. I practiced using the old water pump

how the insert it into position without dinging the mating surfaces. Then gasket

sealant was applied on both sides of the paper gasket very thinly and glued it to the

water pump. Mounting was fairly easy after that.

Photo: The inlet of the new water pump. Notice that one of the three bolts that holds

the bracket above and right of the water pump (which is for mounting the power

steering pump) is stripped.

Water pump inlet

Stripped

Photo: View of the new water pump with the timing belt rollers and tensioning spring

re-attached.

Mounting the intake water pipe was also easier with the AC compressor and its

mounting bracket out of the way.

Now the AC compressor, power steering pump and the brake lines could be

reinstalled.

Now back to the timing belt. In order to take the belt out, the engine mount on the

passenger side has to be removed. This sounds a bit scary, but it was one of the

easiest steps and took less than 15 minutes. I removed the bolt that holds the large

rubber bushing and the two vertical mounting bolts while the engine was supported

from the bottom near the oil pan drain plug with a hydraulic jack. Then the old belt

out was taken out, and the new one put in.

Next the new cylinder head was installed. The first step was to move all the cylinders

to the mid position. Then I cleaned all the threaded holes for the head bolts by

spraying Brakeleen into the holes and blowing it with compressed air. Then a copper

spray sealant was applied to both sides of the head gasket. This was a bit messy, and

parts of the sealant peeled off when I flipped the gasket over to spray the other side.

The gasket only goes one way on the engine deck. There is a tilted oil hole at the rear

center of the engine deck which will only align with gasket in one orientation.

Photo: New head gasket

Photo: New head gasket after applying the copper sealant

Photo: Head gasket on the deck

Placing the cylinder head was not as difficult as I had anticipated. It went in pretty

easily into the alignment holes with only a small adjustment after it was placed. The

head bolts were greased and lightly tightened. The sequence is specified in the Kia

website. Two bolts are shorter than the others and they must go near the timing belt.

The first step is to torque them to 36 ft-lb, loosen them all in the reverse order, and

then re-torque them to 18 ft-lb. This 18 ft-lb seemed awfully low, until I realized that

the required 90-degree turn afterwards raises the torque to about 50 ft-lb.

I found out later that the press-fitted metal hose that comes out of the cylinder head

next to the thermostat (which goes to the heater core and the air intake box) was

slightly rotated inadvertently during cylinder head work. This is not surprising since

the hose sticks out quite a bit at an awkward angle and prevents the cylinder head

from sitting level on a flat surface. The hose was now snagging on the throttle cable. I

found this after reassembling everything. So I had to remove the thermostat and the

temperature sensor and clamp a vice grip to rotate this fitting it back to its original

position.

Photo: Cylinder head mounted and torqued to the engine block

The water pump inlet has a split fitting – one is the return from the radiator and the

other is the return from the heater core with a small branch coming from the air

intake box. The piece that carries the return from the heater core and air box is a long

metal tube that runs under the exhaust manifold and around the engine. This fits into

the split fitting with an o-ring seal, and is only held by a bracket almost a foot away

from the fitting that goes onto one of the exhaust manifold screws. It is a very strange

fitting. I realized that that the bracket had been accidentally bent when removing the

exhaust manifold. It was easy to unbend it, but the exact shape of the bracket in

relation to the fitting is probably important, so I bought a new one from the Kia dealer

for $35.

Photo: New water bypass tube. The original color is green but the old one I had was

blackened over time.

Tightening the crankshaft bolt was not easy, even with a special pulley holder. The

specified torque is 110 ft-lb. Later I discovered that the crankshaft position sensor can

be removed and the flywheel can be easily jammed with a screwdriver to prevent the

crankshaft from turning. This sensor is conveniently located in the front adjacent to

the exhaust manifold. I should have done it this way for removing the crankshaft bolt

as well. It would have been a lot easier and safer than turning the starter with a

breaker bar. It is also worth noting that I broke two Harbor Freight brand socket

extension bars during tightening. They simply twisted and separated at the stem

around 100 ft-lb. I had to get a better quality extension bar.

Mounting screw

Photo: Jamming the flywheel through the crankshaft position sensor hole

Before installing the timing belt, the pulleys need to be installed on the cams. The

intake and the exhaust pulleys are exactly the same and have the same markings, so it

is important to mount them correctly by examining the cam lobe locations and the

firing sequence of the cylinders. The cylinder firing sequence is 1-3-4-2 where cylinder

#1 is closest to the timing belt.

Installing the timing belt was also more difficult than I had thought. The belt was

extremely tight, and I could not get it on the sprockets. The only way was to remove

the tensioning roller. That meant I also had to remove the water pump pulley and the

crankshaft pulley. Having it done it once, it was easier the second time. Even then, I

could not hold the camshafts in the right place due to the tension in the valve springs.

So I bought the “Lisle dual overhead camshaft locking tool”, but it was too large and

would not fit on this vehicle. After many tries, here is a trick that worked for me. After

first lining up the crankshaft, I used a wrench to turn the exhaust camshaft to its

correct position. While holding the wrench, I pulled the belt and slipped it on and used

a cable tie to prevent the belt from slipping off the exhaust cam sprocket. Then I did

the same with the intake pulley. To insert the tensioning roller, I used the wrench to

turn the exhaust camshaft counterclockwise. This tightened the belt on the exhaust

side and loosened it on intake side, which gave it enough slack to bolt the tensioning

roller in place. Putting the tensioning spring back on was also tricky due to the

confined space. I inserted a cable tie through one of the spring windings and pulled it

from the opposite end to stretch the spring and slip it on to the post. The whole thing

was surprisingly difficult for a simple timing belt installation.

Photo: Overhead dual cam locking tool – this did not fit on the Kia Rio. The center coupling

nut was too long, and it is not easy to replace it because it has left and right hand threads

on opposite ends of the nut.

Photo: The spring connected to the tensioning roller

Spring

Photo: This is the opposite end of the spring, near the second roller. It had to be stretched

by connecting a cable tie to pull it and slip it on to the post.

The valve cover had a lot of grime inside and out, and I had to soak and scrub with

Brakeleen several times. The head gasket kit also came with a new valve cover gasket.

After everything was re-assembled, and all the wiring plugged in, I squirted some oil

into each cylinder through the spark plug holes and put some rag into each hole to

prevent oil splash. I also put oil into the oil filter before screwing it on. After filling the

engine with fresh oil, I removed the fuses for the fuel pump and the injectors and

cranked the engine for a minute. The oil pressure warning light on the dash should

extinguish by then. Then I filled it with coolant.

Then I reinserted the fuses, installed new spark plugs and started the engine. To my

pleasant surprise, it started right away without any hesitation. There was lots of

smoke through the exhaust and through the front, but it seems to run fine. The smoke

kept going for a long time, and I was concerned if something was wrong, but it went

away after about an hour. The temperature was fine, and the radiator fan was cycling

normally. It also sounded smoother than before.

In the radiator cap, I could see small flakes of copper paint coming through,

presumably from the head gasket. I may drain out the coolant after some time and

put some fresh one in.

Spring

There were a few other things I had to do, such as fix a small coolant leak in the lower

radiator hose, and install the third piece of the timing belt cover I had forgotten about,

which required having to remove a bunch of stuff all over again, but other than that,

everything ran perfectly.

Photo: Everything assembled and running great

asarangan@gmail.com

2001 Kia Rio idle air control valve

I was having rough idling and stumbling, and every time this happened the check

engine light came on and the code was P1166 (non-specific fuel related problem).

Rough idling could be due to a sticking idle air control (IAC) valve. The IAC is easy to

remove and cheap to replace, but a sticking valve can also be easily repaired. After

doing this, my idle problem was solved, and the idle was smooth.

The IAC is an electrically actuated valve mounted to the throttle body, slightly above

the throttle butterfly valve. If you look down the throttle body, there are two holes on

the side walls. One is for supplying air to the crank case, which returns through the

PCV valve and then goes to the intake manifold to consume unburnt fumes from the

crankcase. The second slightly larger hole goes to the IAC valve. Air flows through the

IAC valve bypassing the main butterfly valve, and returns to the intake plenum slightly

under the butterfly valve. The valve contains a small metal plate that slides back and

forth to control the size of the opening. The neutral position of the plate seems to be

in a slightly open position.

Photo: Location of the idle air control valve

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IAC

Photo: Looking down the throttle body

Photo: After IAC is removed Front side of vehicle

IAC intake Crankcase ventilation

intake

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Photo: Actuator plate inside the IAC valve

The two mounting screws are in a tight spot and I had to use a right angle driver to

remove one of them.

The valve connector has three terminals which are labeled on the body. #3 and #2

opens and closes the valve. If you apply 12V to #2 and ground to #3, it should open

the valve fully. Mine did not open. It was frozen in place even after repeatedly

cleaning with Brakeleen and WD40. I had to force the plate to open with a

screwdriver. Once it started to move, more soaking and cleaning freed the plate and it

started to move smoothly. I put a few drops of oil and actuated the valve several times

by applying 12V.

The #1 wire is the feedback from the IAC, like the throttle position sensor. I did not

check its operation.

The old gasket has to be scraped off and a new gasket should be used when

reinstalling the IAC valve.

asarangan@gmail.com