Recently I blew the head gasket on my 2004 Suzuki Forenza. The engine was overheating very easily. There was coolant in the oil and it was running very rough. I also had to refill my coolant often even though there were no apparent leaks. I read that often times people have white exhaust coming out of their tailpipe when they blow the head gasket, but I did not have this symptom. I opted to go ahead and fix it myself and I wanted to share what was involved in doing the job. I thought I would share my experience with anyone else who might be contemplating this job. I'll make it clear this is the first time I have replaced a head gasket, so you might want to take my advice with a grain of salt. Regardless, I took alot of pictures of the process, and it will probably be helpful to some people. Also, this is alot of work. It took me about one weekend to disassemble everything, and another weekend to reassemble everything. I spent alot of time trying to figure out what exactly I needed to do, so if I did it again it would probably take about half the time. If you do this yourself you will save alot of money. Even with some of the extra tools I needed to buy, I think the total for replacement parts(timing belt, head gasket, thermostat, nitrile gloves, star sockets, torx sockets, oil, etc) was still between $200-$300. If you have more time than money this might be the project for you. For me it was more of a personal challenge and a learning experience. Anyways, here we go.
The first step is to go to
www.autozone.com and login so you can get access to their free vehicle repair guides. They have all the necessary steps, and the bolt loosening and tightening sequences where appropriate. They also give the proper torque values for all the bolts that require it. I did find however that sometimes these instructions listed things that needed to be removed, that really did not. The most notable of these was the removal of the rear timing plate cover. In order to take this off you need to remove the crankshaft pulley which I believe is torqued to 115 ft-lbs. You do not need to take the rear timing belt cover or the crankshaft pulley off to remove the cylinder head so I suggest you do not bother trying. Also, these instructions are not extremely detailed. They are good enough, but I thought it might help to share some pictures.
The following are tools you will need:
- Jack (floor hacks are nice)
- Metric Sockets
- Assortment of socket extensions (I used one that was about 18” long for the flex pipe on the exhaust).
- Torx sockets, male and female
- Assortment of cheater bars
- Metric Hex keys
- Set of metric wrenches (I also used a standard wrench, I believe the largest I used was 15/16”).
- Screwdrivers standard/Philips
- Masking tape to mark hoses and connections.
- Some blocks of wood to hold your engine up after you remove the engine mount.
- Jack stands
- Razor blades
- Hammer
- Magnets help for removing the tappets from the cylinder head.
- Treble lights
- Flashlights
- Torque wrench (Cylinder head bolts are initially tightened to 18 ft-lbs, and then tightened additionally using 3 additional turns of 90 degs)
Now I want to go over some of the steps involved.
- remove the fuel pump fuse and turn your car over a few times to depressurize the fuel system.
- Disconnect the negative battery terminal so you don’t accidental short something to the chassis.
- Drain the radiator
- Drain the oil
- Disconnect the engine control module (ECM) ground terminal post. The ECM is at the middle rear of the engine.
- Next I removed the air filter and the air filter box.
- After the air filter I decided to remove the exhaust manifold. You need to remove all the nuts connecting the exhaust manifold to the cylinder head. Autozone has the loosening sequence. Next you will need to remove the nuts connecting the exhaust manifold to the flex pipe. You might want to be cautious here. This is the only place I broke off part of a stud. Luckily enough was left to put on a new nut during reassembly. The nuts were really rusted on, but some WD-40 helped.
- To actually remove the exhaust manifold you need to loosen the bracket that is holding the flex pipe to the engine block.
- Remove the spark plug cover and the air intake. The air intake is connected with a number of hoses and sensors. I labeled all the sensors and hoses as I took them off so it would be easy to re-assemble.
- Now that the air filter box is out of the way you can remove the serpentine belt. To do this you need to put a wrench on the tensioning pulley and spin the wrench clockwise so the tension pulley swings to loosen the belt. While the tension is removed loosen the belt.
- Now I was at a point where I needed to remove the engine mount. To do this, I believe it is best to remove the right wheel first and put the car on jack stands. Then I placed some wood right under the engine to support it. Once the engine was supported I went ahead and removed the engine mount. I had to do some readjustments to my blocks of wood in the process of doing this.
- Once the engine mount is removed you can take off all the bolts and clips holding on the front timing belt cover. The steel portion of the timing belt cover that is near the engine mount simply lifts out.
- With the front timing belt cover off, you can get ready to take off the timing belt. Before taking off the timing belt I went ahead and aligned all the markings between the crankshaft pulley, exhaust and intake camshaft gears, and the rear timing belt cover. To do this you need to take the spash shield off on the right wheel. I was not able to completely remove mine, but I got enough of it off to get to the crankshaft. Somewhere along the line before this I took off the crankshaft pulley for the serpentine belt. I can't remember if that was fully necessary or not, but I took mine off. To align the markings, I put a socket on the crankshaft with a cheater bar and I brought the markings to the proper orientation as closely as possible. I put some auxillary marking just to make sure.
- Once everything was aligned, I was able to just take the timing belt off with a little effort. You can loosen the idler pulley if you want to make it easier to take the belt off. At this point the autozone manual recommends taking off the timing belt pulley's and the rear timing belt cover. I did not find this necessary and it seems like alot of work. To take the rear timing belt cover off you need to take the crankshaft timing belt pulley off. The autozone manual says to torque this to 115 ft-lbs. It is on there pretty tight. I could not get it to budge, so I just left that stuff on and it was fine.
- Next I went and removed the bolts holding the alternator bracket to the cylinder head and the intake manifold.
- Next I removed the fuel rail. Then I took off the intake manifold. See the autozone manual for the loosening sequence. There is one bolt holding the intake manifold to a bracket that is very hard to find. It is in the very rear bottom of the intake manifold near the firewall. I had to feel around with my hand for awhile to find it. You can see it with a mirror and a flashlight. It is not too hard to get off with a socket once you find it.
- Remove the spark plug wires.
- Remove the Camshaft cover. See autozone for the loosening sequence.
- Remove the intake and exhaust camshaft gears.
- Remove the spark plug/ignition assembly on the driver's side of the cylinder head.
- Remove the camshaft bearing caps. See Autozone for the loosening sequence.
- Remove the camshafts.
- Now you are finally ready to take off the cylinder head bolts. See Autozone for the loosening sequence and procedure. Many people recommend replacing these bolts. My Suzuki dealer did not have them so I reused them. When you take the head out some coolant will spill out. I suggest putting a pan underneath the engine to catch the coolant.
- I left the tappets in until after I took the head out. Once I had the head out, I found that a magnet makes the job of sliding the tappets out easier. I made sure to label each tappets location in the cylinder so each one would go back in the right place.
At this point I could finally see my head gasket. The first thing that stuck out, was that I had three cylinders with carbon deposits, and one cylinder that was very clean. I am fairly new at this, so I decided to look into it further. I found this great video that explains the situation. Diagnosis and Finding Cracks According to this video, clean cylinders indicate locations where coolant may be leaking in through cracks. The next figure shows a closeup of my head gasket. It is pretty chewed up on the far driver's side edge corresponding to the clean cylinder. I suspect coolant was leaking into the cylinder through the head gasket.
- with the cylinder head out, I removed the tappets with a magnet and made sure to label each one so I would know exactly where to replace it. At this point I was afraid the cylinder head was warped so I sent it to an automotive machine shop to be resurfaced. This cost $60.00. Many people on the internet recommend resurfacing aluminum cylinder heads when your head gasket fails. They claim if you don't your head gasket will fail again in about a year. I checked mine with a straight edge and a flashlight, and it seemed pretty flat, but this was alot of work so I went ahead and had it resurfaced anyway.
Here is a comparison of the new head gasket and the old head gasket.
- Once the cylinder head came back from resurfacing, I cleaned the engine block off for the new head gasket. Then I proceeded to reassemble everything. For the most part once you have gone to the trouble to remove everything, putting it back together is actually not that difficult. It does take time though. Anything that had a loosening sequence associated with it will also have a tightening sequence. Autozone will have all that information along with torque specs for the things that require it. I recommend looking over the autozone documents to make sure you torque things down correctly. Make sure you reassemble things in such a way that you do not paint yourself in a corner. There was one part where I was really afraid I did this. I forgot to mention it, but there is a coolant hose/housing on the cylinder head near the alternator that needs to come off. I took this off after the head was off. Once the head is back in place there is no way you can get a star socket in there to tighten it back up. I made this mistake, but I found a 12 point box-end wrench could tighten up a torx head bolt so I was able to tighten it in place. I suggest putting that housing back on the cylinder head before putting the cylinder head back in the car. If you need a new timing belt, this is a good time to replace it. Also, when you put in the timing belt be sure to make all the timing marks line up. You will need to loosen the hex tab on the timing belt tensioner pulley to get the timing belt in. The timing belt replacement was probably the most difficult part for me. Getting the serpentine belt back in can be a bit stubborn too because at least on my car, there is no way to swing the tensioning pulley enough to remove enough tension on the belt to get it on. My wrench always hits something before the belt is loose enough. I solved this problem by jamming pieces of wood between the tension pulley at the max swing so it stays in place. Then I reposition my wrench and swing the tensioner enough to get the belt on. During this operation, it is probably also a good idea to fix whatever the root cause of your head gasket going was. My thermostat was past due for a replacement, so I went ahead and replaced that. The dealer wanted alot of money for this part, but rockauto had it for sale at a reasonable price.
- Once I put everything back in place I changed the oil and I replaced the coolant.
- I replaced the fuse to the fuel pump and reattached the negative terminal to the battery.
- I turned the power on to the car so the fuel pump would repressurise the fuel lines. I turned the car back off and repeated this a few times. I did not turn the car over during this step.
- After triple checking everything I fired the car up. It started right up no problem, but it was running rough. After awhile though it started running fine. I suspect the fuel lines just had air in them that needed to be worked out. Another thing worth noting, was that the exhaust was smoking for a little while. It appears it was just burning off WD-40 and oil. I kept a close eye out for coolant and oil leaks while the car was running but saw none. I also kept a very careful eye on the engine temperature to make sure it was not overheating.
