help overheating

[lasturbo]

Another problem is the fan clutch. My fan still worked when it was running. The easiest way to check is to try and spin the fan with the truck off, it should not wiggle and be difficult to turn. If its easy to do it, or it wiggles, the clutch is bad.

I agree with Marlin, it may be a fan clutch failure or very weak. You need this to pull the air through the radiator. Did you check it yet?? I know this because mine was starting to run higher than normal on the temp guage and when I replaced the fan clutch, fixed it!!

Here was my thread on the fan clutch help I asked for FYI:
http://www.vehicross.info/forums/sho...ght=fan+clutch

[zadam123]

I just checked the fan clutch and it doesn't wiggles an is not real easy to spin. So i don't blow out my motor what is the hottest i should let the temperature run before i pull over to let it cool off middle,3 quarters or up to the first line by the h? Also does the fan have two speeds ybecause it seems like it's spinning but not real real fast

[Marlin]

I just checked the fan clutch and it doesn't wiggles an is not real easy to spin. So i don't blow out my motor what is the hottest i should let the temperature run before i pull over to let it cool off middle,3 quarters or up to the first line by the h? Also does the fan have two speeds ybecause it seems like it's spinning but not real real fast

I am still sticking to the idea that the clutch is bad or going bad. Mine appeared to work just fine, but under any torque it was slipping, and my temp would get hot, even when driving.

As for speed, the RPMs are more important than actual speed. The lower the RPMs, the less combustion, therefore less heat generated. I would NOT run your AC, as a matter of fact, running the heat on full will help reduce the engine heat, but as long as it isn't in the red, you should be ok. You can also crack the hood, cut a hole in the hood I would change the oil after this problem is solved, if it has run hot a little bit, your oil will start to break down. No worries, don't drive it in the red, get it home, should be no problems, I have over heated mine a few times on the trail. Another trick the ZU guys showed me, and this will determine if its the fan, pop the hood, with the truck in park, rev the engine to about 2-3k rpms manually at the throttle body. If the fan isn't sucking a bunch of dirt out of the radiator, your fan isn't working, mine is like a hurricane under the hood when I do that and you can drop temp back to 170 in less than a minute.

[Ascinder]

Another thing to try at least for this time of year would be to drain the antifreeze and just run straight water to get it home. The reason for having antifreeze at all is just to prevent it from freezing(clever name huh?) and to help prevent rust. Water by itself is a far superior coolant and would help keep your engine cooler in the meantime. I would also point out that that in my experience, any time you have weird/bad symptoms occurring right after somethings been worked on, it usually as a cause of that work. Most mechanics will tell you the "oh it's not that" story because obviously it would make them look bad to admit they screwed up, and 99% of the time the customer won't force the issue and make them correct their work. It also gives them more business since they're now working on "some new problem".

[tom4bren]

Another thing to try at least for this time of year would be to drain the antifreeze and just run straight water to get it home. The reason for having antifreeze at all is just to prevent it from freezing(clever name huh?) and to help prevent rust. Water by itself is a far superior coolant and would help keep your engine cooler in the meantime.

Not true. Anti-freeze is a magic elixer. It lowers the freezing point of the solution but it also raises the boiling point. The heat exchange factor could be as you say but if he's already prone to overheating, then he could actually overheat quicker if the water starts to boil.

I've never experienced it but was told that the vanes on the water pump can erode over time. On that tid-bit of info I changed the water pump on the Eclipse when I was having overheating issues. It was fine but it was time to replace the timing belt anyway so I didn't get too pissed.

I don't know if the VX has a similar problem but some engines are prone to getting an air bubble right behind the thermostat. That air bubble keeps the thermostat from responding to the water temp & opening. You have to get a special tool (can't remember what it's called) that fits on the opening of the radiator in place of the cap and allows you to have extra anti-freeze above the level of the radiator. When the bubbles work their way out, the anit-freeze flows in to replace.

If you do replace your thermostat, make sure you get the kind that has the blow-by plug. Supposedly if your engine overheats, fluid will leak by enough to save your engine ... in theory. In reality, take a pair of pliers and pull that plug out before you install in in the engine. Also, install it with the hole at the highest level. It should allow any trapped air to flow through and solve that trapped air problem.

Now to qualify EVERYTHING I've said. I'm still having overheating problems with the Eclipse so I may be out in left field. I've isolated the problem down to a relay that controls the fan (it never comes on).

[Ascinder]

Antifreeze does raise the boiling point, but water is unmatched at absorbing and carrying heat away. It may boil over, but then all that's boiling over is water and you can just add more to get home for far cheaper and less environmental impact than boiling out your antifreeze. I wasn't telling him to run his VX on it, he just wanted something to help get him home with.

[Marlin]

Antifreeze does raise the boiling point, but water is unmatched at absorbing and carrying heat away. It may boil over, but then all that's boiling over is water and you can just add more to get home for far cheaper and less environmental impact than boiling out your antifreeze. I wasn't telling him to run his VX on it, he just wanted something to help get him home with.

And with the extra antifreeze you have since it is no longer in your truck, you can feed that to your significant other as a calorie free sweetener!!! Sorry, just saw the news about the chick that killed her husband and then a few years later her boyfriend by feeding them antifreeze.

[tom4bren]

Antifreeze does raise the boiling point, but water is unmatched at absorbing and carrying heat away. It may boil over, but then all that's boiling over is water and you can just add more to get home for far cheaper and less environmental impact than boiling out your antifreeze. I wasn't telling him to run his VX on it, he just wanted something to help get him home with.

OK, now we're on the same page

I H8d Thermodynamics in college. I do remember about the caloric capacity of H2O. Thinking about Steam Tables still gives me a headache.

I still remember PV=mRT from that class as well.

[Riff Raff]

I would also point out that in my experience, any time you have weird/bad symptoms occurring right after somethings been worked on, it usually as a cause of that work. Most mechanics will tell you the "oh it's not that" story because obviously it would make them look bad to admit they screwed up, and 99% of the time the customer won't force the issue and make them correct their work. It also gives them more business since they're now working on "some new problem".

ASCINDER--- Hmmm, now the total is up to $600 and continues to grow. You are dead-on target about the mechanic!!!

[zadam123]

Another trick the ZU guys showed me, and this will determine if its the fan, pop the hovod, with the truck in park, rev the engine to about 2-3k rpms manually at the throttle body. If the fan isn't sucking a bunch of dirt out of the radiator, your fan isn't working, mine is like a hurricane under the hood when I do that and you can drop temp back to 170 in less than a minute.

Should i try this on a cold Modor or let it warm up a little bit also how do i know if it's sucking dirt from rad. Do I just open the cap and look for bubbles is that what you mean?

[Marlin]

Should i try this on a cold Modor or let it warm up a little bit also how do i know if it's sucking dirt from rad. Do I just open the cap and look for bubbles is that what you mean?

For the sake of others, doesn't matter if truck is hot or not, you can actually feel the air from the fan blowing across the engine, it is really like a hurricane in there, at least with the torque cool fan clutch. Nothing to do with the radiator or anything. If you have any dirt or whatnot in the radiator externals, the fan will suck it through.