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.
After
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.
After
2011 BMW 335xi (e92) - Black Sapphire Metalic w/ Coral Red Interior
(no. 573)
