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Do we need to change that Long Life Coolant anyway?

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 #299382  by paintballdude05
 
This is a long post but please bare with!

So as some of you read/saw in my "rebuild thread" I did a bunch of work to the Intrepid last summer/fall. A lot of this work was in search of a reason behind my car going through so many rads in the past two years. During my investigation, I found a leaking water pump (caused by a bad t-belt tensioner I believe) and some leaking timing belt cover to block seals. My coolant tank was also questionable so I replaced it with a known good one. I put everything back together and used a new aftermarket Spectra brand radiator.

All was well since I started driving the car at the start of December until a couple weeks ago when it dipped down into -20*F weather. I noticed that the car was hot (according to the gauge) but I wasn't getting any heat. It turns out I was low in coolant so I topped it up. I also noticed the passenger side of the rad was wet so I tightened up the hose clamp. From there thinking that I blew another rad I called up CarQuest where I got it. They have been keeping track of how many rads I've gone through and were hesitant to give me a new one. Before they'd warranty it, they sent me over to a rad shop to have the car checked out. He pressurized the system and found no leaks. He used this blue fluid over the coolant bottle to check for exhaust gas and all was good there. I pointed out that the crimps on the radiator tanks looked to be separating. He suggested that I pull the rad out of the car and bring it in to them so that they could re-crimp it. Apart from that, he said everything looked normal so I assumed it was just a hose clamp.

Fast forward a few weeks and now the rad is leaking like a sieve. Pulling the headlight I noticed the crimps on the rad tanks had come apart even more and it was wet in that area. You can see in the pictures bellow how separated they really got. The passenger side tank (inlet) was worst than the drivers side. I pulled the rad out and brought it in to get crimped. I talked to the guy there and told him the whole story. He thinks the damage is coming from pressure surges. He got the rad re-crimped and it looks really tight now, better than new actually. I re-installed it and the car doesn't leak anymore so I'll be good for another little bit but I need to figure out WTH is going on here. I've replaced the following in the last couple of years.

New radiator (duh)
New Mopar water pump
New hoses
New Mopar thermostat (wiggle pin removed to insure no air locks, a bit over a year old)
New timing belt cover to block seals
New Zerex G-05 coolant used every time ($$$ down the drain)
New LIM gaskets done a few years ago
Rad fans replaced (this time around) with a set from a parts car
Coolant tank replaced with a good used mopar unit
Various rad caps used, gasket is good on this one and holds pressure

Now, comparing the Intrepid to the Special with the same engine the Special gets up to operating temperature quicker than the Intrepid. I always thought this was weird. To make it worst, the Special runs exactly at the 3/8 mark on the temperature gauge while the Intrepid is about half way between 3/8's and 1/2. These are somewhat concerning to me, you would think they'd behave identically. Another thing I noticed last night was that the rad fans weren't coming on on the Intrepid until the car was almost at the half way mark. I should have grabbed my laptop with the scanner to see the operating temperature when they did.

One thing that was mentioned to me was that the area where the rad mounts could be twisted causing some odd stresses on the rad. I measured the area where the rad mounts and it seems to be well within a 1/4" of difference, more like 1/8" at most.

As you can see, I'm somewhat at a loss here. I can't keep pulling this thing apart every 3 months to change out the rad. My next step is to go with an custom all aluminum rad but that will cost a small fortune. Does anybody have an idea what could be happening here? The pressure surge idea makes sense, but where the heck is it coming from?

Thanks for the help gang!

Here are the pictures of the rad before getting re-crimped.

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After

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User avatar
 #299384  by evanoliver
 
paintballdude05 wrote:This is a long post but please bare with!
One thing that was mentioned to me was that the area where the rad mounts could be twisted causing some odd stresses on the rad. I measured the area where the rad mounts and it seems to be well within a 1/4" of difference, more like 1/8" at most.
That was my first instinct. Or bent lower radiator support. Something is causing the radiator to torsion.

Either that or you have really (CENSORED) luck.
User avatar
 #299386  by Chrysler1924
 
I ran this problem past a mechanic friend of mine, who's clarity of thought has often netted many "Ah ha!" moments with my own strange car issues. This is what he suggested:

"...What I'd do is get like a pressure washer, disconnect the rad completely figure out which way the coolant flows, and use the pressure washer to flush the engine out, going backwards to how the coolant flows. Because my thought is if he's never flushed the engine, there could be crud built up from some of the rather nasty effects of coolant."
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 #299387  by LUNAT1C
 
How long did the factory radiator last? Are you aware of any damage that might have occurred at any point in the car's life? If there was, what point in time compared to when these failures started?

Have all the replacement radiators been the same brand? My current radiator was obtained from a specialty radiator shop that deals in high quality AM rads and refurbished OE units. My uncle uses them all the time when he rebuilds cars at his body shop. 2 years and 8,000 miles later the car has had zero cooling issues. Maybe you should consider that... there could be an inherent flaw in from the radiator supplier that Carquest uses.

Sent from my DROID RAZR using Tapatalk 2
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 #299390  by Adpros
 
LUNAT1C wrote:How long did the factory radiator last? Are you aware of any damage that might have occurred at any point in the car's life? If there was, what point in time compared to when these failures started?

Have all the replacement radiators been the same brand? My current radiator was obtained from a specialty radiator shop that deals in high quality AM rads and refurbished OE units. My uncle uses them all the time when he rebuilds cars at his body shop. 2 years and 8,000 miles later the car has had zero cooling issues. Maybe you should consider that... there could be an inherent flaw in from the radiator supplier that Carquest uses.

Sent from my DROID RAZR using Tapatalk 2
Good point!

Sorta like those crappy recovery tanks that Dorman makes.
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 #299397  by Maximus
 
I'm in your boat... I'm on my third rad... and believe it or not this one is starting to leak at the tank seam..I've used different brands also. ..I think I'm going to pay the $$$ and go back to oem $487 here in jersey. I guess I was just cheap the first 2 times.
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 #299398  by 300maximilien
 
I went with the cheapest option from RA a Tiawan made TYC for $71.....no issues as of yet
User avatar
 #299405  by paintballdude05
 
Chrysler1924 wrote:I ran this problem past a mechanic friend of mine, who's clarity of thought has often netted many "Ah ha!" moments with my own strange car issues. This is what he suggested:

"...What I'd do is get like a pressure washer, disconnect the rad completely figure out which way the coolant flows, and use the pressure washer to flush the engine out, going backwards to how the coolant flows. Because my thought is if he's never flushed the engine, there could be crud built up from some of the rather nasty effects of coolant."
I've heard of something similar to this happening in our engines. Either from leftover casting sand dislodging midway through the cars life or coolant gunking up the passages like you suggested. It's definitely an avenue of possibility that I will have to pursue come warmer weather.
LUNAT1C wrote:How long did the factory radiator last? Are you aware of any damage that might have occurred at any point in the car's life? If there was, what point in time compared to when these failures started?

Have all the replacement radiators been the same brand? My current radiator was obtained from a specialty radiator shop that deals in high quality AM rads and refurbished OE units. My uncle uses them all the time when he rebuilds cars at his body shop. 2 years and 8,000 miles later the car has had zero cooling issues. Maybe you should consider that... there could be an inherent flaw in from the radiator supplier that Carquest uses.

Sent from my DROID RAZR using Tapatalk 2
The factory rad lasted until about 200k km, or 120k miles, and 8 or 9 years of service at which point the passenger side tank started to leak. The car was involved in a minor front end collision before I bought it (I didn't see the signs when I bought it). The hood and one headlight was replaced. The front bumper was fixed and the upper crossmember was cobbled back together. Upon realizing what had happened, I replaced the upper cross member, headlights and installed a new condenser since it was leaking. The radiator suffered some damage in that crash which included one broken upper "peg". With all this damage, the car still functioned correctly for over 3 years after the fact without any issues.

Replacement radiators have been at least two different brands. I have also tried a used radiator from my parts M and it lasted about 3 months before it went.
Maximus wrote:I'm in your boat... I'm on my third rad... and believe it or not this one is starting to leak at the tank seam..I've used different brands also. ..I think I'm going to pay the $$$ and go back to oem $487 here in jersey. I guess I was just cheap the first 2 times.
Go with an online dealer for pricing. Either order from the online dealer or see if your local guy will match the price.
User avatar
 #299406  by Bill Putney
 
If you want to build your own pressure regulated backflush tool: http://300mclub.org/forums/viewtopic.php?f=120&t=26544
Probably run you $60 or $70 in parts.

I'm a little skeptical that pressure spikes are the problem - the cap *should* to take care of that before it gets to the radiator damage stage. Or perhaps if temp. spikes or pressure suddenly drops and you get flash boiling - but you should see that in the temp. gage as well as loosing coolant thru the pressure cap.

I don't see the difference in temp. gage readings as significant - not enough to affect radiator life. Warmup time can be difference in thermostats - saw that on my '98 3.2 - started acting normally when I changed t-stat again (used Gates both times - one was just different than the other - was put in the correct way both times).

I'm not even going to ask about t-stat being in the correct way, because I know you would have that right.
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 #299407  by paintballdude05
 
This is what I was talking about with the blocked by-pass. Midway down, look for a post by user97

http://300mclub.org/forums/viewtopic.ph ... 20#p285520
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 #299467  by SpeedBallDEVIL
 
Couldn't you rent a rad pressure test kit and see if the pressure fluctuates? And are you sure that damage from the accident hasn't moved the upper or lower rad supports/crossmembers causing the side tanks to be misaligned... Thats my best guess...
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 #299468  by LUNAT1C
 
Maximus... if you'd like I can find out more information from my uncle on the radiator he obtained for my Special. His body shop is in Summit, NJ, (Douglass Autobody, services the Douglass Auto Group) and I imagine the radiator supplier/shop he uses so frequently is nearby. Don't quote me on it, but IIRC, the rad I had him buy was about $150 and CAPA-certified. They installed it January 2011 with Zerex G-05 (which was used in Spring 09 as part of the TB/WP change and replaced that fall with whatever Goodyear used when the factory rad kicked the bucket) that I had provided and I've not had a problem at all (though to be fair the car was only daily driven from March 2011 after PennDOT finally fixed their f*ck-up until early August 2011, when I bought my R/T Charger, about 8,000 miles since March 2011).
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 #299475  by paintballdude05
 
speedballdevil wrote:Couldn't you rent a rad pressure test kit and see if the pressure fluctuates? And are you sure that damage from the accident hasn't moved the upper or lower rad supports/crossmembers causing the side tanks to be misaligned... Thats my best guess...
That's another tool I should buy, along with a spring clamp tool to make removal of the lower rad hose a bit easier.
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 #299685  by paintballdude05
 
Well I'll keep this thread updated on the issue. I think whatever I do I'll start with a really good flush in the spring time using both chemicals and pressure and see what comes out of it. At the same time I'll check the thermostat out once again. Radiator mounts will also be scrutinized once more. In the meantime, I might get bored and design an aluminum rad up in case all else fails.
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 #299699  by FIREM
 
Rad Cap: Test for correct pressure, should "pop" at 17-18#
Mounting: Should be "stress free" as it should float in the rubber mount "slots" as lomg as the lower and upper support have not been accident damaged...
Just a piss poor design.....http://300mclub.org/forums/viewtopic.php?f=88&t=28148
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 #302772  by paintballdude05
 
So just an update. The car is not leaking or loosing anti-freeze so the rad re-crimp worked. It's been getting warmer here in the last little bit, it's in the high 40's today. The car runs per usual just bellow the mid-way line on temp gauge. The other day I got home and decided to put my laptop/scanner on it to see what the temp was at this temperature. Sitting in the driveway the temps were at 221* F with the fans on low. Judging by where the gauge needle was, on the highway the temperatures do go slightly above where it was in the driveway. So, I think it's safe to assume the car easily reaches 225* without problems when cruising on the highway, if not even closer to 230*. IMO these temperatures are just way to high, especially when you consider it's not even 50 degrees out.

In comparison, my buddies '11 Ram 1500 with the Hemi stays right at 200* in similar condition. I'm still planing on doing that flush soon enough. I'm thinking that my internal bypass tube is nearly clogged up causing all theses problems. I might even "splurge" on a new Mopar rad tank.
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 #306688  by paintballdude05
 
So another update. I did a very thorough system flush last weekend. I build a manifold system that hooks up to your garden hose (thanks to Peva for the idea) so that you can control and monitor flow into the system. I started off by draining the system, removing the thermostat and then replacing the housing. I flushed the system with the hose in both directions from the thermostat housing and from the upper manifold location. After that, I buttoned everything back up and pored in some Finish dishwasher detergent that was dissolved in hot water. I drove the car for a day with the mixture and then drained it out. I did another flush using the same method as before. This time I did the radiator too to make sure everything was out of it. I installed a new Mopar thermostat and a new gasket, filled the system with distilled water and let the car get to operating temperature before draining it. I repeated this twice before filling with lastly filling it with coolant.

While flushing the system, the only really noticeable debris that came out was aluminum shavings. At first it was a bit alarming, but I'm going to attribute them to either machining particles stuck in the block at birth or from all the work I did on the front of the block because of corrosion back in the fall. The other thing I found was a green algae like deposit in the system. I'm not sure the reason behind this, but I'm going to assume it was from some bad water I put in the system (I thought it was distilled). When I drained the dishwasher detergent, it came out with a green tint to it. The water that initially came out with the pressure flush after the detergent had a green tint to it too. Ideally, I should have separately flushed the heater core. Next time I do this process on another LH, I probably will.

Overall I have to say I was a bit disappointed with what came out. I was expecting some more buildup in the system. I'm pretty confident the flush I did was sufficient to get everything out, maybe it wasn't. I had a hell of a time getting an air bubble out of the system. It took many tries but it finally came out. The cars operating temperature still hasn't changed any compared to before. I'm starting to think it might be something with the ECU programming that is not letting the fans come on early enough.

I'll keep this thread updated as I go. As of now, the newly recrimped radiator has held up for almost three months now without any signs of the crimps loosening up.

Pictures of the flushing process.

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Mopar thermostat covered in green on the left, Gates thermostat on the right.

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And a trick I saw on one of the forums to hold the thermostat in place, it worked awesome!

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 #306693  by user97
 
Stephan -- from the symptoms you are describing it sounds like you have a blocked bypass in the left head. It mostly occurs in blocks where shavings were not cleaned out at the factory and where some oxidation was allowed to occur. What happens is that shaving naturally accumulate in the driver's side head hot water bypass (to control bottom t-stat) pocket. Then if corrosion is allowed to occur in the system, they rust together forming a restriction to the flow, causing t-stat to open late.

Here is one way to test the theory:

1) Start the car and let it reach the "running hot" condition with fans on (i.e. temp 225-230F, near half way mark on the gauge, fans running, can't get the temp down). Leave OBD II plugged it so that you can see live data.

2) Pull fan relay to stop the fans

If the bypass indeed plugged, you should see something completely counter intuitive -- the temp will start falling rapidly to nearly 180-190F. If this is what you see, you pretty much guaranteed to have a blocked internal bypass. You can either do a "cheap fix" of relocating t-stat or pull the head.

I did countless flushes, changed rad, overflow bottle, t-stat (a number of times) on the car that was having this issue, until I figured out what was wrong.

There is no viable way to flush out that bypass without pulling the head. The only type of flush that made a slight difference, was shooting water UP the bypass (it's the slotted opening in the block where the T-stat sits. I used a small hose to blast water in there -- once the flow became decent I declared victory, assembled everything and started driving. For a day the car behaved perfectly temp-wise, but then all of a sudden it started behaving badly again -- my guess what happened is that I managed to shift the "chunk of debris" out of the way, only for it to shift back into the original spot. From pics of people who actually cleaned out the bypass, the blockage appears to be a solid mess of shavings that is rusted together and is too large to back through the block's cooling passages -- so it pretty much has nowhere to go out of that pocket (unless you pull the head).
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 #306706  by Bill Putney
 
I have no doubt that your persistence will pay off, Stephan, and that you will get it solved.

Perhaps Alex has the right idea. Alex - what if pressurized water (pressurized by blocking off all other parallel paths) were focused in the reverse direction at that point of that possible blockage - is there a chance it could dislodge it - perhaps push it down into an area that could be accessed for grabbing and removing it, or, if it has dropped some but is still not immediately accessible by hand or tool, poking it with a rod to break it into smaller chunks so it could fall further maybe with the assist of more forced back flow? I doubt if anyone could answer that for certain, but it might be worth a try and it just might succumb to Stephan's never-say-die attitude! :)
 #306723  by user97
 
I'd suggest doing the test with pulling rad relay first AFAIK nothing else can cause this weird behavior besides blocked bypass.

Shooting the water as I described achieves the purpose of back flushing the bypass -- however the resulting clump due to shape of the "pocket" is larger ( as far as the length and it would have to go through a 90 degree angle to get out -- there is no room for that) than opening on either side and the clump is pretty solid (shavings rusted together in the mold of the pocket).

Regarding busting it up with a tool -- you have a 70-80 degree angle to contend with -- in the block the bypass is formed by 2 drilled holes -- one is parallel to the water inlet -- the other one to the side of the block.

Unless you find something rigid enough to do the job, yet flexible enough to get there, I do not see a way.

Pulling the head is probably the best option (or relocating the t-stat like I did). I would advise against trying to flush the bypass -- it is time consuming (drain coolant/pull t-stat) and produces unreliable results -- because if you just dislodge it, you open the bypass wider to fix t-stat early close issues, but the operating flow will shove it back as a check valve of sorts