idealconcepts

I think I might have found the reason why truck (89 V6 4wd 5spd, 184Kmiles) is running hot after having an A/C installed. I had a mechanic check my truck out and replace the thermostat and radiator fluid. They stated the clutch fan looked good and the radiator itself looked good. They pressurized it and noticed that the radiator cap needs to be replaced and the radiator neck has a crack. They said the leak isn’t bad and all they could see was a little bubbling. I'm picking up the truck in an hour and will ask them to show me the crack. They quoted me $220 to correct the problem with the neck. Is this a reasonable price from what you guys have seen? What I think I might try to do first is see if I can seal the crack with some automotive epoxy first if the crack is location that is sealable, any thoughts on this? Also does anyone have any experience with changing the radiator neck themselves? I want to see if this is something I might be able to do and save a little money, if it isn’t very difficult. I plan on getting the radiator cap from the dealer and the radiator neck if I decide to change it as well.

Thanks,

Ryan

paranoidandroid

NO. they are overcharging. go to a radiator shop and have them patch the crack. I had a crack on the radiator of my old nissan maxima, 45 bucks to patch it up and clean out all the gunk inside. Granted, this was back in Houston, but I dont think it will cost that much more out in CA.

paranoidandroid

also, i wouldnt seal it with automotive epoxy either. the crack needs to be welded back. remember, the radiator needs to withstand very hot temps. unless your epoxy can withstand such high temps without becoming soft or warping, dont do it. You could prevent it from being able to be patched in the future and have to get a new radiator anyway

manyunk

I would just replace the radiator. I bought one at autozone 115 with lifetime warranty. Put it in myself .

YotaJunky

Can you post any pics? If the crack isn't too big, I'm wondering if you could wrap a rubber collar around the neck and then tighten it up with a clamp? Otherwise, just get a new rad. I installed one myself on Sunday and it only took about 2 hours.

Here's a link to my write up with pics.

https://www.yotatech.com/forums/f16/radiator-replacement-how-pics-55979/

Troy

idealconcepts

Thanks guys for the quick comments. Got the truck back at lunch time but didn't get a chance to take a look at the radiator crack. I'm going ot dealear afterwork to pick up a radiator cap and hoping this will help a little.

paranoidandroid - if I still have a problem with overheating, I'm going to start looking at radiator shops to see how much they charge to patch it.

manyunk - thanks for the tip on Autozone, I have their PS pump from there and no problems so far since it was put in last month. I might grab the radiator if places around here charge ( to patch the one I have now) close to the cost of a new radiator.

Troy65- I'll see if I can post pics once I look at the radiator after work. Hopefully the digital isn't acting up. The mechanic said the crack was so small that it might be diffcult to see it, but if I can see it I will take pics. Great write up, wish I found one smilar a few years back when I did the same for my 91 Legend, took me 2 days a total of about 5-6 hours going with minimal knowledge on how to do it. It worked after the hoses were cut to proper length and pressure tested. If I need to replace the radiator I might just try it, your write up inspired me.

Thanks again guys, this site is great.

Nic

I doubt the crack is causing your problem, unless it is running too low on coolant. I have an 84 Camry that has a 2 inch crack on the top of the radiator. It would fizz when it reached operating temperature. Every so often I would have to top it off. It has never run hot though. I have since had the timing belt and water pump/thermostat replaced-just for maintenance reasons. I have used JB weld on the crack and have not had any problems or leaks since. The top of my radiator appears to be plastic. I may end up replacing it later since the whole top of the radiator appears weak, but right now it is OK.

Perhaps your thermostat is not working like it should? Is it a Toyota thermostat? Even if it is new, it may be defective or the wrong type. I do know a Toyota thermostat is much better made.

One other thing, your radiator may be stopped up and not allowing water to flow through it adequately, thus causing overheating. I had a 77 Corolla that had overheating issues and it turned out to simply be a gunked up radiator.

EDIT: I thought of one other thing. If your hoses are weak, the suction from the water pump will collapse the radiator hose and restrict the flow of coolant.

idealconcepts

Thanks Nic for the comments.

Just to make sure everyone is on the same page, when I refer to my truck running hot, I mean the temp gauge reads higher than it use to before I had the A/C installed, I’m rarely using the A/C so I am fairly sure running the A/C isn’t causing my truck to run hot, because it is not on when it runs hot. The gauge is fluctuating slightly, maybe an 1/8 of an inch typically when I drive and occurs when I stop at a light, I assume because of the reduced flow of air getting to the radiator, because of the condenser. If the truck sits for a long time (approx. 15 minutes) running in traffic it can get to the half way point but has never gotten above that. I guess I am worried that when it gets to the summer time, typically in the high 90 and low 100s, this could get worse and I would like to solve it before hand. I think I am going to take my gut instinct on what is causing the problem and my experience with my 91 Legend that ran very hot and almost over heated a few times. I had taken it to the dealer 7 or 8 times and they could never find out what was causing the running hot/over heating problem. They pressure checked the radiator several times and did not find any leaks or detect any problems, I never saw any radiator fluid on the ground. After going back and forth to the dealer for about 6-7 months I ended up changing the radiator and hoses. This finally solved the problem and the car never over heated after that. I ended up selling it a few months later because I didn’t want to deal with any future problems. I had also problems with my Integra radiator leaking, and a pathfinder running hot and overheating. I’m assuming the Japanese cars’ radiators can’t handle the valley heat year after year.

Nic,I replaced the radiator cap and with the old cap you could hear it fizz after the engine was turned off. I was hoping that the new cap would resolve the running hot problem. After I replaced the radiator cap I let the truck run for about half and hour checking for the crack the mechanic mentioned (I think they said it had a crack because they could hear the fizzing noise). I think I might be in agreement with you regarding the crack not causing the overheating. Oh and the cap is from Toyota. The timing belt was replaced in 2002 when the truck had 160K miles (it has about 184K now) and I am pretty sure the water pump was changed some time after 100K, this was done the previous owner. I believe the clutch fan was worked on sometime after 100K also, I don’t have the records in front of me at the moment, and the mechanic mentioned yesterday that the clutch fan and radiator looked good. Does flushing the radiator really get all the gunk out of the radiator? Do they remove the hoses and attach another set that pushes all the gunk out of the radiator? Can there be gunk where the radiator hoses connect to the engine, I guess in the engine?

Troy65, I was ready to take pictures but you can’t see the crack and as I mentioned I think the fizzing noise could have been the old radiator cap that the mechanic might have thought was a crack, or I could be wrong and it has a crack. I even ran a paper towel all over the neck of the radiator before I started the truck and after and could never find any liquid.

Manyunk, how long ago did you install the autozone radiator and did you have any issues installing it (i.e. hoses had to be cut or were difficult to connect)? Have you had any issue with the radiator or cooling with your truck since you installed the autozone radiator? Also is there a core charge for the radiator? I have their rebuilt PS pump for about a month or two now and haven’t had any problems.

What I am thinking of doing, and I appreciate any comments you guys might have with it, is - Wait a week or two and see if the truck is still running hot. If it does run hot, I will replace the radiator (based on Manyunk experience with the autozone, hopefully he didn’t have any problems with it) with the autozone brand. I plan on using the new radiator cap and can I re-use the thermostat that I just had installed? I thought about flushing the system but the shops around here charge any where from $50 to $80 dollars, where I could just purchase the Autozone for $115 and I could install it or have a shop do it for $80. I would also get new houses from the dealer and be done with the radiator and not have to worry about it again. I’m hoping this will resolve the running hot problem and I can move on to the idea of lifting the truck. Any comments, suggestions, hints, or thoughts on this plan are appreciated.

Nic

I don't have time to say much, but the backflushing thing will probably help very little. Years back when I had it done, I had the radiator out and the shop had a pressure hose that basically squirted water from the bottom of the radiator hole out the top. It flushed some of the gunk, but it didn't totally fix the problem. The temp would start to climb if I sat idling too long. I think mine was more severe than yours though.

I think replacing the radiator would be the better option.

Bu the way, I was referring to the thermostat earlier. Maybe that is the issue. If the thermostat is for a hotter temperature it may be staying closed too long. It would be easy to change that out and see if it fixes the problem.

YotaJunky

"Does flushing the radiator really get all the gunk out of the radiator?"

I flushed my rad out twice within a month and then changed it out shortly after that with a new rad. I noticed rusty looking fluid coming out of my bottom pipe after the old rad was removed and even after 2 flushes. For me, the answer would be "no". This may depend more upon the corrosion in the core and any junk such as corroded rubber from the pipes etc...

Troy

YotaJunky

My truck only had about 125k miles on it before my rad started to leak from the bottom. IMHO, I would change your rad and be done with it. I got a new one with a lifetime warranty for $230 (Canadian dollars) and installed it myself in under 2 hours. It was a lot easier than it I had anticipated. Also, it would be a good idea to check your hoses and change the ones that have a tendency to fail, such as the large top and bottom ones.

Troy

idealconcepts

Thanks Nic and Troy65. I called Autozone and they sell the radiator for $189, and online it sells for $166, I might see if they will price match it, and there is no core charge. This changes the cost drastically. Manyunk got a pretty good deal ($115) on his, where are you located, when did you buy it, and did you buy one for a 89 V6 4wd 5spd? I looked at the thermostat before it was installed and it had an 82 number on it(degrees maybe???, I don't remember if it said F or had the little supscript o). I think I am going to completely skip the flushing and if the truck temp continues to fluctuate in the next week or two, I thinking of just replacing the radiator and the upper and lower houses and be done with it. Thanks again guys.