Road Rage

Did both today - took a couple of hours. Here are some tips, highlights:

1) Make sure you have 2 gals of Type 2 coolant available - I drained the whole system and one gallon was not enough. Drain the coolant, having removed the radiator cap first.
2) Lots of those little plastic clips have to be removed to get the undercar shielding out of the way to access the fan switch and drain plug- store them in a bag or you will be paying about $4 per clip - outrageous!
3) You will need either an offset box end wrench or a deep socket, size 24MM to remove the fan switch. Remove the two-wire connector first of course.
4) Thread in the Mugen switch and tighten - snug it up but do not obsess over it, or overtighten it. I put some silicone grease on the o-ring but that is optional. Replace the drain plug. Grease that o-ring too.
5) The thermostat is hard to get at - bolts are 10mm cad plated - I could not get a box or racheting box end wrench in there, so I broke the bolts with a 6-point 10mm 1/4" drive on a 3" extension. Fortunately, Honda did not overtighten them and they came loose rather easily. They are long suckers, so once you break the bolts free, dry your hands and use the extension separated from the ratchet driver, and twirl it - do not lose these bolts! I have a magnetic tray that keeps them from migrating to the 4th dimension, where all lost car parts end up basede on my experiences wrenching for 40 years.
6) The lower thermostat bolt can be attacked by sliding in from the front of the car - the upper bolt is best attacked coming in the from the driver's side, where you can position ther
wrench and guide it with both hands, one coming through a small gap on the right of the thermostat (your right hand therefore).
7) As the bolts loosen, have a catch pan ready - you will get coolant on you, so be sure to wear eye protection, and an old shirt. When the screws are detached, pull on the lower radiator hose and it will allow access to the old thermostat. You can suspend the hose on some of the smaller rubber hoses nearby.
8) Note the position of the old thermostat - the bleed hole mounts "UP", and surprisingly says so in English - the Mugen is all Japanese.
9) Position the thermostat with the bleed hole at 12 o'clock to the top of the engine (lining up with the input hole from the aluminum thermostat housing). The thermostat seats into the housing, not into the aluminum thermostat cover which is attached to the lower rad hose. You could try using some grease to hold the thermostat in the housing, as it tends to fall out, and if you do not seat it correctly, you will not get a good seal and invite a leak.
10) Attach the lower bolt first - that will allow you to see the thermostat gasket and that it is seated symmetrically in the housing. Hold the tthermostat cover with one hand while you attach the lower bolt - snug it up, but do not tighten it - you still have to align the upper bolt.
11) Tackle the upper bolt - snug it up - then tighten it to about 8 ft/lb, I just did it by feel, by do not overtighten it. Then tighten the lower also to the same torque.
12) Keep the front of the car elevated. Remove the rubber stopper in the heater bypass tube at the back of the engine bay - it is black and held on by a spring clamp - a small adjustable pliers will allow you to loosen it. Put in on the cowl where you won't lose it!
13) Loosen the intake air bleed - it is on top of the intake, near the front, and is a cadmium plated bolt with a nipple on it - use a 13mm to loosen or remove it. Again, put it somewhere safe!
14) Start pouring the Type 2 (plus WatterWetter if you plan to use it) slowly into the radiator. The heater bypass will overflow a little. Replace the stopper. Then add some more coolant until it comes out of the intake bleed - snug that down.
15) Fill the radiator up.
16) The shop manual syays to leave the rad cap off and then start the car, and let it go through two heat cycles (fan on, fan off, fan on, fan off). I found that before the fan cut in, coolant spilled out the radiator hole, so I installed the radiator cap.
17) Start the car - monitor the temp gauge - go to the engine bay and check the upper radiator house, the rad, and the lower hose - watch out for fans and no hanging jewelry or clothing!
18) MAKE SURE THAT THE ENGINE IS NOT OVERHEATING BEHIND AN AIR LOCK! If the upper rad hose is really n
hot, but the lower one is cool, and the gauge is going up, you probably did not install the thermostat with the bleed hole in the right spot. Shut down to avoid overheating.
19) If you did it right, as I did, the car cooling fans will cycle on and off a few times. Shut down the engine. Now, check for leaks around the thermostat. If none is found, then pour some lukewarm water over the intake bleed hole, along the thermostat housing, etc to remove any coolant that may have dripped.
20) Once everything seems ok, re-install all the under car shielding.
21) Make sure there is coolant in the reservoir - also check the coolant level in the reservoir after the car has cooled several times over the next few drives.
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If your car is a 2004, the normal temp will be 7 bars, rising to 8 at stops, and then the fan will kick in as the engine starts to head towards 9 bars. It never makes it to 9, at least it did not today with temps in the 60's.

I have no idea what the temp gauges in the 00-03 will show - Gernby or JL9000 probably can answer that.

By my estimation, oil temps should stay around 200 degF, which is hot enough to avoid sludge and allow the additives to do their job. It will rise under hardriving or racing.

If this allows the car to maintain some timing advance, that is a good thing.

Slows2k

Normal temp for a 00-03 is 3 bars, 170 degrees actuall temp, measured in the block coolant drain bolt with an Autometer electric gauge. BTW, the 3rd bar lights around 150 degrees.

Road Rage

Thanks - I will attach an OBDII scanner tomorrow and watch and report the bars. One thing is for sure - once the "normal" bar is reached, the bars will not budge until the "get a new head gasket" bar appears. I will likely add aftermarket gauges as you did with linear reporting in the future.

Slows2k

I believe the 4th bar on 00-03's lights around 220. Which is a bit to hot for my tastes.

The good thing is Honda uses a pretty tough steel shim head gasket. I've seen Accords with similar gaskets cooked until the plastic timing covers melt, but the head gasket seal is intact.

reds2

You don't have to loosen the under shielding to drain the coolant. There is an opening in the shield to access the drain knob. I broke my OEM fan switch because my socket wasn't deep enough. I also lost one of those damn bolts on the thermostat housing.

JL9000

Great post.

The pre-04 temp gauge normally shows three bars, but in cold temperatures it may drop to two bars.

Asura

Thank you Road Rage for a very informative post. I plan on doing this very soon.

revhi

I have a mugen thermstat now, but never installed it because I heard rumors that the car might not warm up all the way. Let me know if you have that problem.

Asura

[QUOTE]Originally posted by revhi
I have a mugen thermstat now, but never installed it because I heard rumors that the car might not warm up all the way.

mikecl713

i have spoon cooling mods
my temp shows at 2 bars for 95 percent of the time
probably because of winter. even in the 60's its mostly at 2 bars and 3 at stops.
just because ur coolant is at 2 bars doesnt necessarily mean ur oil temp is the same
am i correct?