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Cooling Ticking Timebomb, how is your Cooling U-tube?

82K views 140 replies 88 participants last post by  3X163  
#1 ·
So I’ve been pretty quite as of late and don’t think I’ve seen this cooling issue addressed before. This last Friday I discovered a small cooling leak originating from the front side of the engine of my Cartoon Car. So I took the undertray off and slid under to take a look at what might be the problem. What I saw made me realize that yes, this is a Lotus alright. The coolant leak is coming from the A120E0017F Connector, which shorts a vestigial cooling run to the oil filter heat exchanger we don’t have since we have front mounted oil cooler/s. So basically these cooling lines are dangling down with a U-shaped Al tube in front of the engine. Well, the hose length on my car is just right so that the Al tube (P/N A12E0017F) rest and rubs on one of the oil line fittings. Hence, it rubbed long enough to create a pin hole leak. It’s a 0.080” relatively thick wall tube with ~0.58 OD, so it took it’s time to rub thru.

I think all the Fed Elise/Exiges have one or two front mounted oil coolers, so you might want to check to see if your U-tube is rubbing. If it is, it’s a ticking time bomb in your coolant system. Take a look at the pic from the Service Parts List (Item 20). If you are under the car, looking up, that hose assy and U-tube are basically right above the oil filter assy.

The other thing that sucks is I’ve got take the car to the dealer for them to cover the part under warranty. While I understand they need to dot all their “I’s” and cross all their “T’s”, so they can look at it and determine the same conclusion. Flat-bedding my car to the dealer ship at my expense sure seems like I’m getting shafted for a obvious poor hose routing and support from the factory:wallbang:. I mentioned I can bring you the failed part and pix of what everything looks like, but they need the car regardless. I know another local Elise owner I hold in high regard has noted the same rubbing issue, it’s bound to be a problem on other cars out there. Anybody know if there is a service bulletin floating around for this?

I’ve got the local parts department checking on the cost of the U-tube part, it wasn’t in their system, since it’s never been ordered. If it relatively cheap, I can replace it myself. I’ve repositioned the hose assy higher, so it won't rub like the original position. Now you can access the U-tube from the topside of the engine bay, still tight confines thou.

Well, as these cars continue to age, these kinds of interesting failures and oversights will continue to reveal themselves. If I get a chance tonight, I will post up a few pix of the area of interest and the removed U-Tube.

Hope this helps my fellow ETer’s.

-Frankie-
 

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#2 ·
D@MN! Holes in hardlines? That does suck. Can you band-aid it and drive it to the dealer yourself, or is distance to dealer considerable?

Thanks && Please keep us posted.
 
#3 ·
I assume it's aluminum - don't remember. Another option would be to pull the part and take it to a shop with a TIG welder. Won't be pretty, but it'd be pretty functional - probably cost $5.

Bleeding the cooling system won't be much fun though!
 
#4 ·
I've already supplemented a brass 90º barb-barb fitting that should get me to the dealer if need be. If the part is relatively cheap (which in a sense makes this even more asinine), it's just not worth my time and effort to go all the way to the dealer BS paper mill. I bet if I took it to the dealer, they'll bleed the cooling system as well as they did when they replaced my rear brake caliper-eek-...

Yep, that U-tube is Al, and I might take it to work and get a buddy in the Aero lab to weld it up (hopefully it's 6061). Heck maybe I'll find a scrap piece of comparable Al tubing and fab one up. Once I hear back from the parts dept, I figure out what I feel like doing. There a few other things I want the dealer to resolve, this might just be the time to do it.

Here are a few pics of the culprit. I was fortunate that I found this in my garage. If anything, next time you change your oil, take a look at this hose assy.
 

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#29 ·
+1!!!! Thanks Frankie! I know you push your Elise hard and its great of you to share your findings with others on e-talk. :up:
 
#7 ·
Nice catch on this one--and I just had my car on the lift yesterday for an oil change when I could have inspected the line. Oh well, I guess it is just another excuse to put the car back up on the lift and do some more inspecting. I swear this car is like owning an airplane--you have to do annual inspections to keep it roadworthy and safe!
 
#8 · (Edited)
If that's a pin hole, I'd hate to see what you'd consider a big leak!
-eek-

Looks like the end isn't in very good shape either.
 
#10 ·
Something like this:D
Image


Yeah, the psuedo beads on the ends of that tube are definitely weak sauce:confused:.
 
#9 ·
And while we're on the topic of preventative maintenance for hoses, check all the stainless braided flex hoses you can access and make SURE there is NO contact between the braided covering and anything else. Since the braided cover is made up of fine S/S wire, it is easier than you think to abrade through the covering by just rubbing a little on a nearby surface. I've seen an oil cooler hose on a bike rub through to the inner hose in less than three months due to one flex hose rubbing on one beside it. If there is any contact with the braided flex hose, it's a good idea to isolate the contact area by overwrapping it with some of the poly spiral tubing (Pep Boys, etc.), or whatever works for you.
Jim
 
#12 ·
I'll take a look at this. Thank you for the post.
 
#15 ·
Yeah, just wonder how many Fed Elise/Exiges are rubbing away as we type:thwack:.

Funny thing, with all the track time I've logged on my Cartoon Car, I thought it was just normal to that the valve train was sounding louder. After I replumbed the cooling line and started her up, she oddly quiet. If you hear some slight mechanical noise in your engine bay, it just might be your U-tube saying "Wassup...":wave:

I've got a tech in my Aero lab material ID'ing the tube so I can be certain it a weld will hold. Will post up what we find:)....
 
#16 ·
I'm changing my rear tires right now, so I went ahead and checked this - however I couldn't find it. I have an early 05 with twin oil coolers - so it may not be an issue for us. There was no tube running near there besides an electrical wire which had shielding with no scarring on it.

I went ahead and checked my toe-link bolt, and they were both tight (16,000 miles with autocross day before)
 
#17 ·
My Cartoon Car (VIN 31386) is a dual front oil cooler car and I'd suspect any Fed Elise/Exige with front oil cooler(s) could potentially have rubbing issues with this hose assy.

Like Nathan said, you should be able to see this area by taking the RHS rear wheel off and looking towards the forward side of the engine. If your tube isn't in that spot, I'd be curious to see where the routing is, if its a different hose assy, just to make sure it's not rubbing on something else:shrug:.

I've attached a pix from the Service Parts List where I've highlighted the hose assy run, for a NON-front oil cooler(s) car. Imagine the U-tube shorting the run instead of tying to the oil filter heat L-to-L exchange shown in pic. This is what my car looks like.
 

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#20 ·
So the local dealer part guy told me a fresh part from England would be ~$23, taking about 9-12 days.

The material ID showed the tube to be a 6061 alloy, so I got the lab to put a filler weld on it.
 
#21 ·
I was wrong, the U-Tube is on the dual oil cooler models as well. It was hard to find though, and I tugged and tugged on it and couldn't get it pulled off to the side to get a very good visual inspection. However, feeling it - it didn't seem to feel damage.

Theres also no way to check it with just the rear tires off, you must remove the under tray.
 
#22 ·
Theres also no way to check it with just the rear tires off, you must remove the under tray.
You are right, my under try was off when I too some pic's from the RHS rear fender well. Here's a pic from that angle with the car running, even with all that rubbing ont he tube, it was just barely dripping. The blurry thing to the left is my phat BADARAONE.

Man, and I was all ready to have some good fun at MSR CW this past Saturday. Thanks:clap: Toad for letting me get a few fun laps in your Elise:coolnana::up:...
 

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#23 ·
Interesting...

I checked mine as well and the u-tube was zip tied down to one of the oil cooler lines :shrug: . Not sure if this was done by a dealer or the PO. I don't see any "bad" abrasion, and I'll try to post a pic to show all later. The last pic is my attempt to tie the u-tube to the larger cooling line? I'll haver to check it at the next oil change. Thought others might be interested in seeing another...

Jim B.
 

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#24 ·
I checked mine as well and the u-tube was zip tied down to one of the oil cooler lines :shrug: . Not sure if this was done by a dealer or the PO. I don't see any "bad" abrasion, and I'll try to post a pic to show all later.
Jim B.
That's the way mine came from the factory as well.
 
#32 ·
Mine was zip tied and when I removed the tie and checked, I saw an area that was about to burst open. I also split a radiator hose and wrapped it around the U Tube and then zip tied the whole thing into place. Shouldn't be a problem now. I suspect there will be quite a few Loti with coolant leaks in the future.
 
#27 ·
I don't think mine was ever zip-tied from the factory:sad:. For reference, I picked her up in Mar '05.

From the pix BlueMustang has shown, there still some rubbing even zip tied. Can't say zip tie of steel on aluminum is an optimum solution.
 
#30 ·
Me, I'd get a short length of hose, split it, and tie whap it around any sign of abrasion then re-tie-wrap the whole thing back down.

This is exactly what I did, mine was tie-wrapped from the factory and this probably slowed down the wear but it was worn (not to the point of leaking though at 25k miles)
 
#31 ·
Will check mine in the spring...before warranty runs out.
 
#33 ·
Did a bunch of work on my car today and remembered to look at the u-tube. It looked like it was getting pretty close to wearing through. I've got about 21,000 miles on the car and I think it might not have made it another 5,000. I wrapped it in rubber and ziptied it, but I'm thinking about a longer term solution to put in place the next I have the car up on stands.
 
#35 ·
I really appreciated this thread.

Found same situation on my car; tie-wrapped heater hose around U and tie-wrapped the whole thing out of the way.

Thank you very much.
 
#36 ·
CHECK YOUR "U-TUBE" SOON

This is not just a high-mileage problem.

I just checked my connector for the feed and return hoses and there is wear at 6000 miles. Granted, I do a bit of spirited driving on twisty mountain roads but nothing excessive.

Here is my connector on my 2007 Elise, again at 6000 miles:


Here is what I used to shield the connector for now, zip-tied around the tube. It is a rubber shim for bicycle handlebar attachments (lights, heart rate monitors, etc). I figure the rubber will help hold the connector in place, buffer any movement, and protect the connector. Really it is the only thing I had lying around ;):


Here it is in place:


And again:


Don't let this slide too long or you'll be sorry :no:. Check your feed and return hose connector soon.