bloc
SILVER Star
Try their parts drill-down for your year model cruiser/LX and see what comes up. I’m curious why that number wouldn’t work.
2008-2018 Radiator Failure and Public Service Announcement (1 Viewer)
- Thread starter jclarke450
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
bloc
SILVER Star
Very odd. Might as well try calling them.
And in a final bit of great news, Lexus HQ agreed to reimburse me $650, which halved the cost of the entire project and more than covered my parts costs for the radiator!
So, how did you get Lexus HQ to reimburse you? Did you call them up or go to the dealer to start the conversation? I'm probably going to be doing this in the spring and it would be nice to know that the cost of the parts (rad., water pump, etc.) would be mostly covered.
So, went to South Austin's site and plugged in the part number for the radiator. I just laughed out loud at the "Lexus tax".
The Lexus part performs 25% better.So, went to South Austin's site and plugged in the part number for the radiator. I just laughed out loud at the "Lexus tax".
View attachment 2518863
bloc
SILVER Star
So, went to South Austin's site and plugged in the part number for the radiator. I just laughed out loud at the "Lexus tax".
View attachment 2518863
And, the box will have both toyota and lexus markings on it. For the extra $120 you think they'd wash off the toyota logo stink..
CharlieS
GOLD Star
For whatever it is worth, I ordered my Toyota radiator online and had it shipped and it arrived in pristine condition. The box they use protected it well. I know that isn't everybody's experience, but if you aren't in a rush, it might be worth a try.
If it were me, I would do everything within my power to buy it locally, and inspect it before leaving. The box it comes in is simply not suited for shipping as an individual parcel, imo. Both the original radiator and the replacement that they added extra cardboard to had some level of fins crushed.
New to me, 2013, 132k miles. Removed the decorative radiator top this weekend and….no surprise.
SINCE NOT YET LEAKING, this is my < $15 attempt at “structural reinforcement”. Add a few shallow grooves near the crack edges (oriented with the low stress direction) to basically try and piss the crack off. Roughen up the surface with 180 grit paper (oriented with the high stress direction). Patch using JBWeld plastic. The red dash is the OEM radiator contour, whereas the blue dash is the contour I was going for.
As has been pointed out, the crack-before-leak indicates these cracks are initiated on the outside. To reduce the propagating stress, my only hope is to have enough strength from the patch in the radiator’s depth (short direction), which is why I was trying to maximize the patch size in that direction.
Lexus radiators typically fail in the plastic/aluminum joints at 150k-ish (see my signature before you ask me how I know!). Hopefully this repair will enable that type of failure instead.
SINCE NOT YET LEAKING, this is my < $15 attempt at “structural reinforcement”. Add a few shallow grooves near the crack edges (oriented with the low stress direction) to basically try and piss the crack off. Roughen up the surface with 180 grit paper (oriented with the high stress direction). Patch using JBWeld plastic. The red dash is the OEM radiator contour, whereas the blue dash is the contour I was going for.
As has been pointed out, the crack-before-leak indicates these cracks are initiated on the outside. To reduce the propagating stress, my only hope is to have enough strength from the patch in the radiator’s depth (short direction), which is why I was trying to maximize the patch size in that direction.
Lexus radiators typically fail in the plastic/aluminum joints at 150k-ish (see my signature before you ask me how I know!). Hopefully this repair will enable that type of failure instead.
It's still going to fail soon. This will buy you a little time, but it's going to happen. There have been several repair posts like this, and it always ends the same. Start budgeting for a new radiator and get it on the schedule before the summer heat hits.
Meh -- I'm not convinced of your certainty. You are PROBABLY right, but not high enough probability for me to commit to a further preemptive repair.
Based on my non-exhaustive research, I certainly did not find facts to support your observation. I saw a few pre-leak reinforcements with no apparent conclusion. I saw a few post-leak repairs that did not last (I wouldn't expect those to last -- leak sealing would be unlikely).
Regardless, everything is a temporary repair, right? A new radiator with a better design still has a finite life. This was an easy application, so let's wait and see? I appreciate your advice.
Your crack wasn't too bad anyway. It definitely didn't hurt things. A few have cut them open after failure, and that plastic appears to fail from the inside. Just anecdotal observation.
@tincan45, that is one reason I attempted this as mitigation, because the crack was still relatively minor. I'm not entirely sure what you mean by "fail from the inside"? These cracks start at the outside surface at the step ("stress riser"). As the crack continues cycling (from max pressure to min pressure) and gets wider (longer), they also get deeper, until they eventually get thin enough near the inside surface to fail due to internal pressure. The only hope I have in slopping a bunch of exotic goo on it is to stop the two sides from moving apart. If they can stay put (relative to each other), then the crack will not continue to grow and the leak will not occur.
That is why I was intentional with the deeper grooving on the sides -- I was trying to strengthen the tie between the two sides that are trying to move apart. And that is why I was intentional with the selection of a heavy grit sandpaper, and the orientation of its grooves -- I was trying to provide a stronger shear plane for the exotic goo to "attempt" to hold the two sides from moving apart. If this was applied earlier, it would have more chance of working.
I have seen some try to correlate this failure to mileage. I'm not sure that will be a good correlation, because it primarily depends on number of stress cycles. If someone drives an average of 20 miles per cycle (from cold low pressure to hot high pressure back to cold low pressure), they'll be at 8000 cycles in 160k miles. Contrast someone who might have shorter average drives per cycle, e.g., 10 miles per cycle. They'll be at 8000 cycles in 80k miles, and just as prone to fail as the 160k driver.
Is there any reason to think the radiator cap is somehow failing to relieve pressure, or relieving at too high of a pressure? I seriously doubt it, as it's a relatively simple and predictable device.
That is why I was intentional with the deeper grooving on the sides -- I was trying to strengthen the tie between the two sides that are trying to move apart. And that is why I was intentional with the selection of a heavy grit sandpaper, and the orientation of its grooves -- I was trying to provide a stronger shear plane for the exotic goo to "attempt" to hold the two sides from moving apart. If this was applied earlier, it would have more chance of working.
I have seen some try to correlate this failure to mileage. I'm not sure that will be a good correlation, because it primarily depends on number of stress cycles. If someone drives an average of 20 miles per cycle (from cold low pressure to hot high pressure back to cold low pressure), they'll be at 8000 cycles in 160k miles. Contrast someone who might have shorter average drives per cycle, e.g., 10 miles per cycle. They'll be at 8000 cycles in 80k miles, and just as prone to fail as the 160k driver.
Is there any reason to think the radiator cap is somehow failing to relieve pressure, or relieving at too high of a pressure? I seriously doubt it, as it's a relatively simple and predictable device.
bloc
SILVER Star
It isn't that simple. A major factor here is the plastic itself becoming compromised from the heat of normal use. See this post for a picture of that phenomenon. This will occur with time at temperature being the primary contributor and have very little to do with number of stress cycles.
Realistically it is a combination of material degradation and stress cycles, and even if your patch reduces the effects of those stress cycles I doubt it will completely eliminate them, and besides, the plastic is still slowly becoming compromised anyway.
I like your thoughtfulness and consideration of details, but as I've stated before the biggest problem is you can no longer monitor propagation of the crack and now if it lets go you may not have any warning. Or, you might change the failure mode and instead of a weep it could be a more dramatic failure. As for no documentation of patches applied before evidence of leak failing.. this thread isn't the only place stuff like that gets posted. I know I've seen at least a couple over the years.
Well, yes, I said it wasn’t a good correlation! 
But then you point out other contributors to various failure modes? The topic I’m addressing is the crack initiation, growth, and eventual thru-wall leak. That is primarily due to stress cycles at an overstressed location, not time at temperature. Time and temperature are not the primary contributors. If so, then the new radiator design will fail in similar time, right, regardless of its redesigned stress riser? Several of my Lexus radiators on the top hot side discolor, and although I’ve never tested the material, I’ll readily concede that some sort of material degradation occurs over the years/miles. But that does not cause this particular type of failure. I think I recall your pics (I saw a few), and recall observing some internal surface cracks in the “brown” plastic. Again, I consider that “normal degradation” as none of those were leaks, right? The entire top side material is the same and at essentially the same time/temperature environment – thus those are not contributors even though the material continues to degrade.
Additionally, I could still take your time/temperature belief as primary contributors and demonstrate how poorly that corresponds to mileage. Similar comparison, except substitute speed for time. An average speed of 50 mph (morning commuter jumps on interstate for most of their drive) will achieve 3200 hours in 160k miles, whereas an average speed of 25 mph (stop and go drives to school, errands, city driving) will achieve the same 3200 hour mark in 80k miles. Thus, poor correlation to mileage regardless of stress cycle or time at temperature. {which is why low mileage vehicles aren't necessarily any better}
I agree with what you call “the biggest problem”, but that doesn’t mean it’s a big problem. To me, the big problem is that I can guarantee a leak will occur in a relative few cycles if nothing else is done – which means just replace the radiator now with the redesign (several will advocate the “better safe than sorry” stance). I chose to try a $15 dollar/15 minute patch with a belief that I understand the failure mode, and that this repair attempt could mitigate. I don’t need to eliminate the stresses…I just need to reduce the stress to less that what is required to propagate the existing crack. You are right in that “a more dramatic failure” mode could be created, but I seriously doubt that will happen. I think partial separation of the patch will occur, allowing seepage to escape and be observed. Please note how my patch is not that wide…that too was intentional. Continued crack propagation will eventually peek out the side and leakage could be observed. There is no benefit to having the patch be wider (but there is benefit to having the patch maximized in the front to back direction).
Perhaps, to mitigate your concern, place a piece of string perpendicular to the crack orientation, at the crack’s center, and lay it toward the front of the vehicle, before applying the exotic goo. The small compromise in strength is negligible, but now you have a leak path to monitor?
But then you point out other contributors to various failure modes? The topic I’m addressing is the crack initiation, growth, and eventual thru-wall leak. That is primarily due to stress cycles at an overstressed location, not time at temperature. Time and temperature are not the primary contributors. If so, then the new radiator design will fail in similar time, right, regardless of its redesigned stress riser? Several of my Lexus radiators on the top hot side discolor, and although I’ve never tested the material, I’ll readily concede that some sort of material degradation occurs over the years/miles. But that does not cause this particular type of failure. I think I recall your pics (I saw a few), and recall observing some internal surface cracks in the “brown” plastic. Again, I consider that “normal degradation” as none of those were leaks, right? The entire top side material is the same and at essentially the same time/temperature environment – thus those are not contributors even though the material continues to degrade.Additionally, I could still take your time/temperature belief as primary contributors and demonstrate how poorly that corresponds to mileage. Similar comparison, except substitute speed for time. An average speed of 50 mph (morning commuter jumps on interstate for most of their drive) will achieve 3200 hours in 160k miles, whereas an average speed of 25 mph (stop and go drives to school, errands, city driving) will achieve the same 3200 hour mark in 80k miles. Thus, poor correlation to mileage regardless of stress cycle or time at temperature. {which is why low mileage vehicles aren't necessarily any better}
I agree with what you call “the biggest problem”, but that doesn’t mean it’s a big problem. To me, the big problem is that I can guarantee a leak will occur in a relative few cycles if nothing else is done – which means just replace the radiator now with the redesign (several will advocate the “better safe than sorry” stance). I chose to try a $15 dollar/15 minute patch with a belief that I understand the failure mode, and that this repair attempt could mitigate. I don’t need to eliminate the stresses…I just need to reduce the stress to less that what is required to propagate the existing crack. You are right in that “a more dramatic failure” mode could be created, but I seriously doubt that will happen. I think partial separation of the patch will occur, allowing seepage to escape and be observed. Please note how my patch is not that wide…that too was intentional. Continued crack propagation will eventually peek out the side and leakage could be observed. There is no benefit to having the patch be wider (but there is benefit to having the patch maximized in the front to back direction).
Perhaps, to mitigate your concern, place a piece of string perpendicular to the crack orientation, at the crack’s center, and lay it toward the front of the vehicle, before applying the exotic goo. The small compromise in strength is negligible, but now you have a leak path to monitor?
bloc
SILVER Star
Well, yes, I said it wasn’t a good correlation!
Additionally, I could still take your time/temperature belief as primary contributors and demonstrate how poorly that corresponds to mileage. Similar comparison, except substitute speed for time. An average speed of 50 mph (morning commuter jumps on interstate for most of their drive) will achieve 3200 hours in 160k miles, whereas an average speed of 25 mph (stop and go drives to school, errands, city driving) will achieve the same 3200 hour mark in 80k miles. Thus, poor correlation to mileage regardless of stress cycle or time at temperature. {which is why low mileage vehicles aren't necessarily any better}
I agree with what you call “the biggest problem”, but that doesn’t mean it’s a big problem. To me, the big problem is that I can guarantee a leak will occur in a relative few cycles if nothing else is done – which means just replace the radiator now with the redesign (several will advocate the “better safe than sorry” stance). I chose to try a $15 dollar/15 minute patch with a belief that I understand the failure mode, and that this repair attempt could mitigate. I don’t need to eliminate the stresses…I just need to reduce the stress to less that what is required to propagate the existing crack. You are right in that “a more dramatic failure” mode could be created, but I seriously doubt that will happen. I think partial separation of the patch will occur, allowing seepage to escape and be observed. Please note how my patch is not that wide…that too was intentional. Continued crack propagation will eventually peek out the side and leakage could be observed. There is no benefit to having the patch be wider (but there is benefit to having the patch maximized in the front to back direction).
Perhaps, to mitigate your concern, place a piece of string perpendicular to the crack orientation, at the crack’s center, and lay it toward the front of the vehicle, before applying the exotic goo. The small compromise in strength is negligible, but now you have a leak path to monitor?
While I did say "major" I didn't mean to imply "primary". I personally believe both contribute equally, with the possibility that that weighting shifts based on use. Without the stress riser, the tank would eventually fail, but definitely not as quickly and most likely not always in the exact same spot as we see with these. And, without the degradation on some portion of the cross section of the material, that stress riser may not be enough to compromise it and start a structural failure.
But that specific stress riser with this level of material degrading is what we have.. at least from stock. Chicken & egg, so to speak.
Complicating your stress cycle argument, is my current radiator. I got the vehicle at 105k with a visible crack but no leak. Put a new OEM radiator in, which at the time was the old design. Now at 157k miles I have the very beginning of a crack, and for the 52k miles in between I've had remarkably low stress cycles, as most of that mileage has been long trips all over the country.
Again, I like your approach, but personally I'm in the better safe than sorry camp, though my ability to quickly do the radiator myself and likelihood of problems occurring far from home if they occur at all do weigh in to that opinion.
Now in month 5 of JB Weld. Due to Covid the truck basically only sees longer trips and far fewer cycles. No signs of leak yet.
All is well here to. Same driving habits and cycles as before patch and about 10k miles a year.
The grain of the plastic runs from side to side as per all of the previous pictures of cracks that propagate from an unnecessary(opinion), improperly designed riser that exceeded the bend allowance for the material used. I extended my patch 1.5 times past the next internal rib on each side as per the worst picture I could find. Changing out the radiator just seemed to easy for me and I had experience with fiberglass/epoxy so that just seemed like more fun.
I did some rough comparisons from CF to FG and the 8 tapered layers of CF material used to build up and round off the riser would be close to if not greater than 12 oz FG.
You didn't just imply it as a primary contributor, you TYPED it rather clearly!!
Regardless, you make good points.Assuming those longer trips would also indicate higher average driving speeds, doesn't this also complicate your "time at temperature" argument as well as my "higher cycle" argument?
You should try my Fix 2.0!!....
Last edited:
