I have a 1998 Toyota Camry 4 cyl, car has 240,xxx miles on the motor, has been a great running car up until the other day. I noticed I was hearing the sound of boiling water from under the hood when I would get home late at night when I turned the car off in my driveway. It was too late at night to pop the hood and check things out so I waited till the next day.. Parked it on level ground and checked out all the fluids, Radiator has lots of coolant and is still nice and bright green. Turned the car on and let it run and the fans work. Got in the car today and drove it around a little and I notice the temp gauge and it was way too high, usually its right in the middle, but it was about a quarter away from being all the way hot. Lucky for me I was not too far away from home, so I turned around and headed back. When I stopped at lights I noticed steam coming from up under the passenger side hood (coming from the over flow tank) And the needle would still be real high up saying its running hot when I’m stopped at the light. When the light turned green I would slowly take off and the temp gauge would drop down to the middle for a while and then slowly work its way back up to hot again.

Pulled in the driveway finally and turned the car off, once again I could hear the boiling water sound. So I opened the hood and its steaming from the over flow tank and whole passenger side of the engine bay is wet.
Other than from the over flow tank the car is not leaking from anywhere else.

Right now I’m hoping I don’t have a blown head gasket or worse a cracked head(but then again there is no white smoke coming out the tail pipes or anything like that) I don’t think it’s the water pump. Hoping just the thermostat is bad and is just sticking closed. Or something small of that nature, need new radiator cap needed maybe? Catalytic converter was just replaced last year.

Plan on buying a newer Camry sometime at the end of this year. So I'm looking to get this car running right to at least last till then.

What do you guys think? Any more info needed to further help you help me please say so. I'm a little mechanically inclined. Mainly on older domestic cars with carbs and such, but I don’t think Toyota's are that hard to work on. If its nothing too major I could get a Haynes and get my hands dirty no problem.

I think I want to tackle on the thermostat first though, is there any good brand I should go with that you guys may have good experience with? Also what degree stat should I put in? And what antifreeze do you guys usually run with?

Verify the fans are running when it's overheating. If yes then I would suspect either a clogged radiator or weak pump, especially if that pump has been in there for 240K+ miles.

Both a cap and a t-stat should be fairly cheap at your dealership. They will make sure you get the correct degree t-stat. Use whatever coolant your manual specifies - probably the typical green coolant or maybe Toyotas' universal red.

Had a chance to pull it into the garage today. Started it up and let the car run a little until the car got to operating temperature.. Got in the car the hit the gas till about 2k rpm, and noticed the gauge going up a little. Then I went to see if the fans would cut on yet- Nothing. Got back in the car and go it up to 3k rpm and the gauge almost jumped to fully hot, once again the fans did not come on.

Funny cause the day I had to turn around and drive it back home cause I noticed the car overheating the fans were on and working when I got it into the driveway.

I don't own the correct tools to check for the bad fuses or relays, or even if the fan is just completely dead so I'll wait till a friend of my come by and I'll report back.

EDIT:

I let the car cool down a bit and when back and took the cap off the radiator, well I couldn't see a drop of coolant in the radiator or the over flow tank. Also cant seem to find a leak anywhere. Looks like a pressure test is going to be needed too cause I have no idea where all that coolant went that was just in the radiator the other day.

Drained the oil, needed an oil change.

Drained all the coolant, from the radiator only not the engine. And Im about to go pickup a new thermostat in about 30min and some distilled water.

Also picked up a new radiator cap, it was busted.

Where can I bleed the system at when I get ready to fill it up?

.................................

Don't touch the cap with the H on it. That's the high pressure side of the A/C. You bleed the cooling system right where you poor in the coolant, only with the radiator cap off. Change the oil, then refill the coolant in the radiator with a 50/50 mix of 100% coolant and water. (Check the concentration of what you bought as some coolants come already mixed to 50/50.) Also, don't forget to put the 50/50 mix in to the overflow tank till it reaches the full mark. Then elevate the front of the car slightly; the front portion of a sloped driveway is enough. Start the car with the radiator cap off and turn the heat to high. Run the car like that at idle for about 45 minutes. Most of the air bubbles will be out by then. Refill with the 50/50 mix of coolant and water as needed during the process, as the air bubbles bleed out. When done, shut off the car and install the radiator cap. Recheck the coolant overflow tank after a couple of days of driving. You may have to top it off just a bit as a few remaining air bubbles work their way out of the system.

Mike

Cool, thanks mike.

I planned on doing exactly what you said. But I figured there would be a valve inline with some of the hoses from the radiator or heater core somewhere(that I couldn't seem to find)

Like what was done here.

http://www.youtube.com/watch?v=zUpXgAJ1gjU

I just viewed the video. No such bleeder valve on the Toyota 5SFE 4 cyclinder engine. You have to bleed it the old fashioned way, as I described above.

Mike

Okay good to know.

On another not though these two 10mm nuts are well....driving me nuts!! :banghead:

I got the bottom one nice and loose, but that top one is a little hard to get to when the alternator and everything else right there is on.

EDIT:

Got both nuts loose, I thought these were supposed to come completely off though??

As shown here, I got them loose but when I got my ratchet on there they just keep turning and wont come off.

Even when I go to tighten the bolts back up they still just continue to turn and turn and never tighten back up.

http://img191.imageshack.us/img191/4048/21993383.png

Those 2 nuts are supposed to come completely off. I'm not sure if you can get the thermostat and it's o-ring (referred to as gasket in your picture) out and in without completely removing them. You may have to get a light and your head down there while these nuts are turning, to see what exactly is happening. It could be the studs themselves came out of the block and that's why the nuts just keep on turning. You could actually be turning the studs. If so, they should just screw back in to the block. Look at the bottom one first. It should be easiest to see.

Mike

Here is a pic, the bolts are just there turning and turning. There is no longer any grip to them. If I use a boxed wrench the studs are not moving anywhere but I can clearly see the bolts moving.

http://img689.imageshack.us/img689/1412/dsc02657o.jpg

Please lets use a common reference for these parts. The parts that are hexagon shaped are nuts. The parts the nuts thread onto and are sticking out of the nut with exposed threads are studs.

Please clarify what turns when you place a wrench on the nuts and turn them. What has changed from when the nuts were able to back off the studs? Have the studs turned at any time, or have only the nuts turned? It is unclear if the studs are frozen to the nuts and turn with the nuts, or are the threads damaged on the studs (or nuts) so that the nuts turn freely and will not turn off the studs. You should be able to move the nuts off the studs if the threads in the nuts are really badly damaged. It appears that one nut has been turned further off the studs than the other since there are fewer threads showing above the nut on one stud than the other. Do you know what you did to make the nut on the left stop unthreading off the stud?

If the studs turn with the nuts, spray some penetrating oil on the nuts (PBBlaster or Liquid Wrench, not WD40). If the studs are turning with the nuts, can you turn only the nuts (not the studs) with a box-end or open-end wrench if you grab the unthreaded end of the stud (do not damage the threaded portion) with a vice-grip pliers?

If the studs don't turn, can you unthread the nuts if you carefully grab them with pliers so that you don't damage the threads on the studs, and pull while you rotate them counterclockwise, or do the studs turn? Above all, do not damage the threads on the studs.

It very much bothers me that you are having a problem with both nuts on the thermostat housing. It is almost always the case that only one nut or stud shows a problem unless something unusual has happened. Have you only turned the nuts counterclockwise? or have you turned them clockwise at some time?

The studs do not move at all, just the nut when I turn them.

I used a ratchet with a 10mm socket to get to the top one cause I was having trouble with using a box wrench with it hitting the manifolds and alternator because I could only turn the nut so far till the end of the wrench would either 1. Hit the manifold or 2. hit the alternator at some point.

Clock wise or counter clockwise the nuts just spin and spin on the stud. I cannot turn them at all by hand but of course easily with a tool.

I tried pliers but it was kind of hard for me to to get a good grip under there.

I'm going to assume at some point or some how I damaged the threads within the nuts themselves not the actual studs. Or possibly I damaged the studs threads under where the nut still is.

No matter whether you've stripped the nuts or the studs, you have to take the same approach at this time. Place a socket or wrench (preferably a socket) on a nut and figure out which tool or pair of tools (screwdrivers, needle nose pliers, etc) you can use to gently pry between the housing and the nut to push the nut away from the thermostat housing. If the nut is really tight to the housing, you may have to use a different approach. At least one of the nuts appears from your photo to be loose enough to get something between the housing and the back of the nut.

Apply gentle pressure on the back of the nut as evenly side to side as you can while you use the socket to slowly turn the nut counterclockwise. Theoretically, the remaining theads will catch at some point and the nut will begin acting normally, or at least loosely close to normal and you can remove the nut.

If one of the nuts is still really tight against the housing, you may have to grab it with a pair of needle nose pliers and pull strongly while turning. A less desirable method would be to get a slightly undersized socket (maybe a 3/8" 12-point socket that has been filed slightly to be a tight fit) and tap it gently onto the nut with a small hammer so that it tightly grabs the nut, and you can then use the socket to both turn the nut and pull on it to achieve the same effect as prying between the nut and the housing as I described above. In any event, you need to find a way of pulling the nut or prying the nut while turning it counterclockwise. Ruining the nuts is not important since you can easily get new ones. Be careful and not crack or deform the housing. It may be necessary to apply pressure to the nut to be able to turn it and tighten it against the housing before you can tap the socket onto the nut without damaging the threads of the studs.

Once the nuts are removed, you can remove the housing and assess the threads on the studs. If they are unusable, then they will have to be replaced. If the nuts are stripped, then that is the best of possible problems and just get new ones. Clean up the threads on the studs if necessary with a die so that they are undamaged. If you use a die to clean up the stud's threads, place a rag over the water jacket so that any metal shavings do not get in the water jacket.

For almost any work described above, you will probably have to loosen the powersteering pump and/or alternator.

Maybe someone else will have better solutions for you to try.

Brian has given you some great advise. Try the methods he has suggested.

Looking at your picture, I'm beginning to wonder if you have stripped the 6 corners of the nuts enough so that they are not actually turing when the socket is on them. Have you actually seen the nuts turn, or are you assuming they are turning because the socket is rotating? You probably will not be able to see them turn when you use the socket on them. Are you using a 6 pointed socket or a 12 pointed socket? With the way those nuts look I would use a 6 pointed socket so you will be grabbing the nuts along the sides of the hex, not just the corners.

Mike

@ Brian R.
Lots of good advice. Unfortunately I had to fill the car up with oil and coolant to get it out of my garage as I have a more valuable car I like to keep in there vs. sitting in the driveway. I will be making room on the side of my house to pull it in and give it another go.

If my studs are damaged, would anyone happen to know where I can get a set of direct replacements for them besides stealership if possible.


@ Mike Gerber
I cant recall if I was using a 6 point or 12 as I have a few different ones in a 10mm socket size. Yes I have actually seen/watched the nuts turn as I used the socket. If I want I can put the socket on just halfway and turn the nut as well.



Either way whenever I get them off, I would like to go ahead and replace the studs and nuts. Though I feel that's something that will have to be done if I want to or not. Besides all of this my fans still are not working, they were just fine a few days before I even made this thread. Going to test the motors on both fans today. I found some part numbers for the fan relay on autozone and NAPA website. But could not seem to find the part numbers for the fuses on either site.

Be careful. It is not likely that your cooling system will hold pressure. It will probably dump all your coolant on the ground very soon if the engine heats up with the radiator cap tight. That will ruin your engine in a minute if you're driving.

BTW, from the position of the nuts on the studs, my best guess to what has happened is that someone at some time has overtightened the nuts and stripped either them or the studs. The torque on them is only 78 in-lbs (6.5 ft-lbs).

Whatever is damaged, you may find it easiest to further damage the threads and then work with the very loose fastener. If I were a betting man, I'd bet the nut threads are the ones that are stripped.

In addition to my previous post, I would like to mention that in tight quarters and if the nuts are really tight against the housing, a pair of needle probes with either or both a straight and 90 degree bend can be used to gently pry between the nut and the housing. See the links below for examples.

http://www.sears.com/shc/s/p_10153_12605_SPM685007501P?vName=Tools&keyword=probes&prdNo=11&UnitNumber=&storeOpenDayInd=today&blockNo=11&blockType=G11
or
http://www.sears.com/shc/s/p_10153_12605_SPM223956539P?vName=Tools&keyword=probes&prdNo=14&UnitNumber=&storeOpenDayInd=today&blockNo=14&blockType=G14

Get replacement studs or nuts from the dealer parts department. If you don't get the correct composition nuts or studs, you may get serious corrosion problems. The nuts and studs have to be the same material for long-term. They will not be substantially more expensive from the dealer, unless you are worried about saving a couple of dollars.

I actually have that exact set in the first link.

I just got done testing the cooling fan motors and they both work, check out the fuses and relay and they are good.

Last thing I can think of is a bad temp sensor, as far why the fans do not come on anymore??

You can test the temperature sensor and find out if it is functional. If you haven't, download the service manual for your car in the sticky post at the top of this forum.

Bump

Little update. I took the car to a shop a while ago, because I was still curious to where all the coolant going. The last time I filled it up with coolant and checked it again a few days later only to find out all the coolant has leaked to somewhere and I wasn't sure where it was all going.

Turns out there was a nice little hairline crack or so in the radiator. Shop wanted close $500+ to replace the radiator. :rofl:

Obviously I was not about to pay $500++ just to replace a radiator. The shop was literally two blocks down the street so I brought her home and parked it on the side of the house.

Went and collected some parts and got the new radiator+new hoses+new clamps+new temp sensor. Got it all in within a few hours or so.

Filled it with coolant, got all the air out of the system. Then I let it run for about 20mins

Car hasn't over heated..YET! But the car got to about the middle or so I would say on the temp gauge. I waited and waited with the car still running and the fans still never cut on. Fan motors are good, fuse and relays are good, new temp sensor. So Im still not sure whats up. Will the fans no work with a bad thermostat?

I still haven't been able to get those bolts off, I tried everything you guys suggested and no luck.

I have another shop in mind and pretty much only works on toyotas, I plan to take it over there to let them figure it out before I ruin something.

I was getting ready to take my dremel with a small cut off wheel and cut the damn Nuts off the studs. :evillol: