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Boss 302 Oil Cooler Leaks

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KBBOSS1086 said:
Mine did failed at the track...turn 1 at Pocono at about 130mph! Not only was it very dangerous but it cost me 2 sessions and a lot of sweat till I rigged a fix.
I know the feeling. Mine went at Road America and that's not a track where you want to be driving sideways :eek:
 
cloud9 said:
I know the feeling. Mine went at Road America and that's not a track where you want to be driving sideways :eek:
When YoPauly's let go his friend Bret was right behind him in his Z06 and he almost lost it.
 
For those who track their Boss, and even those who don't, this stuff is important to know about. Sure, some people by nature just like to complain about things, but most members of this forum seem to be earnest in their desire to learn everything they can about these cars, good and bad, and share their experience and knowledge for everyone's benefit. These cars are still new enough that we're still in the discovery phase of learning about real and potential problems, some of which could have very bad consequences on track. The more we learn and share our knowledge, the better we'll be able to prevent these potential failures from occurring and ruining our track day or weekend, or worse.
 

Grant 302

basic and well known psychic
We are mostly above whining and bitching here...except, you know, when it comes to TracKey for GTs ;)

I'm actually glad this came up so I can be a bit more prepared.
 
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Agreed with all.
I'm *so* glad that someone identified this and posted it up.
It is far from complaining, as this is a serious safety issue. Imagine diving downhill on an off camber corner doing something like 75mph...and you start spraying coolant everywhere - your front tires, the road, your rear tires!!! Off you go into the wall. And worse, that stuff on the ground is wicked slick and it affects those behind you.

With this being brought to light, I will not be hitting the track until I get this resolved (or simply swap to water wetter). Pretty scary stuff.
 
boro92 said:
Agreed with all.
I'm *so* glad that someone identified this and posted it up.
It is far from complaining, as this is a serious safety issue. Imagine diving downhill on an off camber corner doing something like 75mph...and you start spraying coolant everywhere - your front tires, the road, your rear tires!!! Off you go into the wall. And worse, that stuff on the ground is wicked slick and it affects those behind you.

With this being brought to light, I will not be hitting the track until I get this resolved (or simply swap to water wetter). Pretty scary stuff.
Fortunately when mine started leaking it wasn't catastrophic. I was going under the Corvette bridge (unloaded and off camber) and started going sideways when I thought I was well within normal grip limits. I wrote it off to something on the track and kept plugging. Then as I came downhill into 8 I had what seemed like brake fade, but didn't have the classic signs since the pedal was firm; just took longer than normal to bite. This of course led to left foot braking coming into Canada Corner under WOT at 140 mph to make sure I had pedal and it was solid as a rock. I thought this was all very weird so I pit in after 14. The first step was check the coolant overflow and it was at the hot level so I didn't think it was a coolant leak. Then I put it on jack stands to bleed the brakes. After pulling the driver front I see fluid all over the wheel well and am like WTH?? Since the coolant was full and I could tell it wasn't oil I figured power steering fluid. Then I remembered we have electric steering :eek: It took a lot of digging but eventually pinpointed those aluminum fittings on the sandwich plate. Fortunately it wasn't worse. Obviously it was misting onto the tires and rotors.
 
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I keep a extra set of new hoses with me..just in case. If need be I can removed the darn Boss cooler if it becomes a problem and just go air to oil. I pigging back my oil coolers right now. It is a nice thing to know ahead of time so you can be ready for it if it happens. No need to complain, This is info we can all use if you have a water to oil cooler on your car. I thought it good Info myself. So thanks for letting us know.
 
I am warming up (no pun intended) to getting an air-oil cooler, but I am not giving up on the stock cooler yet since I don't have time to really track all that much. So in the spring when I change the coolant to water (mostly to clean out the "pepper" in the reservoir) I want to look at the stock cooler more carefully.

I feel like we may be jumping the gun on removing the stock cooler for dd/HPDE/autoX duty where I suspect the air-oil might not work well (low airflow). So far we know of a few different failure modes (please correct me if I missed one from the other thread):
1. aluminum inlet/outlet tubing on cooler fractures. (KBBOSS1086)
2. Leak at inlet/outlet where it goes into cooler (YellowBoss, cloud9)
3. Inlet indented from swaybar contact, possible explanation for no. 1 and 2 (Black Boss)
4. Hose leaks at connector. (ArizonaBOSS)
5. MFR QC: forgetting to crimp the quick connect. (NFSBOSS)

5 we can easily check for, and is the only one that seems to have happened at the lower radiator hose manifold.

I suspect that 1 through 4 might all be related to the hose routing too close to the sway bar, like BlackBoss mentions. If his has that issue, then I am going to bet we all do. He doesn't mention it in his sig, but is Black Boss on lowering springs? Would that locate the sway bar closer to the cooler? The engine also moves quite a bit with the stock mounts. So could the swaybar and engine movement coupling to the hose be enough to eventually make the connectors or metal inlet/outlet tubing fail? It sounds like the majority of the problems are developing after track use, so that made me suspicious also. If that is the case, I am willing to bet that a more flexible and sensibly routed hose and spinning the cooler a bit away from the sway might solve the problems not related to QC. AND if you replace the hose you can install a thermostat valve at the lower radiator hose output.

Anyone think I might be on to something?
 
I think your on the right track (pun intended :)). It may be a tolerance issue re the sway bar, depending on the lower hose and cooler orientation. As I mentioned I rotated my lower hose to increase the clearance, but engine movement may still cause contact -- I will check this weekend, as I put duct tape on the swaybar after the modification to confirm if contact is still occurring.

I have standard engine mounts and stock LS springs. Lowering is on this year's winter mods list.....
 
It's a good theory and one I had for my own situation. I had a sway bar mount break on the driver side and the sway bar pushed up into the cooling hoses flexing one of them into the accessory belt which sawed through it. The aluminum fitting subsequently failed at the next track event. I suspect it may have been slightly bent from that incident which weakened it. I need to check the routing on mine again to make sure the sway bar is not making contact with the hoses as the engine flexes. I do have the prothane motor mounts so hopefully it's not an issue in my case.
 
I think we are making some progress! I have to crawl under my car once the warm weather comes back to see what kind of clearances we are dealing with, but I am wondering if the cooler can actually be rotated at all? After looking at the install directions from Ford, I think all I have to do is loosen the extended threaded insert and the cooler will be free to rotate and point the inlet and outlet in a better direction. Then use flex hose and an in line thermostat. Maybe I just have not beaten on the car enough to get the swaybar to contact the plumbing. If anyone knows of a suitable in-line thermostat please let me know. I believe the hose I.D. is 3/4" on the stock cooler.
 
We discovered mine when replacing the engine after a valve spring failure. I have to check the sway bar clearance also but it is possible it happened by accident. I assumed after reading this thread it was weaken from before the engine was pulled as we were careful, before reading this I had not put much thought into this. One thing to keep in mind is those that have had failures are people using the car at many track events, driving hard or both.
 
Just took the swaybar off -- it's still making contact. Here are the pics after 10 days at the track. Swaybar (I put Duct tape on to check contact -- it's actually worse in spite of the modifying the lower hose orientation -- probably because I'm driving the car harder and this is inducing more engine movement) :

IMG_0709Medium_zpsa26f3f1e.jpg

Cooler pipe flange:

IMG_0708Medium_zps27cfae2f.jpg

I'm going with a large Air/Oil Cooler and eliminating the stock Water/Oil Cooler.
 
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FWIW, I'm surprised that the tracks let you run anti freeze, I think you would be much farther ahead to use a product called Water Wetter, at least if you blow a hose off you can still steer the car unlike the "ice" that comes form anti freeze.
 
Agree, but either way this is not a good way to spend time at a track weekend. Apart from needing the replacement parts for the cooler and/or hose, you'd need to re-fill Coolant and depending on the failure mode, Engine Oil as well ......
 

jneary

Performance Fords
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Norcal
I have to say, even in a car that is only tracked on the Bay Bridge, I am thinking that this is a potentially bad failure if the sandwich plate fails and starts leaking coolant into the oiling system. I am thinking that an oil to air cooler is a better bet.

Mine just turned over 20,000 miles and no issues with ANY leaks. I am actually impressed by that. The rear main seal must be a good design.

John
 
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Blackboss, thanks for your investigation, findings and photographs.
Now we know exactly what to look for and why :)

By the way, is your car lowered and if so, what is the front spring rate you are running?
 
Car was on OEM (LS) springs (upgrade to coil overs in process). I don't believe ride height or spring rate make a difference. Engine mount stiffness (or lowering) would (my engine mounts were OEM).

Also you cannot rotate the cooler -- it has location lugs that fix it's rotational position. The only option is to rotate the lower radiator hose to increase static sway bar clearance. One other thing -- I had dynamic contact with the OEM Radiator support. When I switched to the 302S Radiator and Fan I also put the Steeda Radiator support in to reduce weight -- the Steeda bar reduced static sway bar clearance a little so I added spacers to the Steeda mounts to maintain stock clearance.
 

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