I have a 97 80 and have been having trouble with slight overheating. When I am underload in the summers in AZ the airconditioning will turn hot and stay that way till I get off the gas or start going down hill. I was thinking that during the winter I would try and fix the problem with an Al radirator and assessory fans. Does anyone know of a good source of these items and if this would help my problem?
Aluminum Radiator?
- Thread starter clarkrw3
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Clark - I would not wait to repair the cooling system. Assuming that your hot AC is due to the temp cutoff, it means you've already hit a dangerous condition that needs to be addressed.
The best source for parts (assuming you plan to DIY) is CDan. If you do need a new radiator, I would also recommend you go with the 3-row brass radiator instead of the stock aluminum part. Not only is there more cooling capacity, but it costs less too.
But other parts that you might want to investigate are the fan clutch (often a problem), the thermostat, and the water pump (look for seeping from the vent hole). You might be experienceing any one or more of these problems.
The best source for parts (assuming you plan to DIY) is CDan. If you do need a new radiator, I would also recommend you go with the 3-row brass radiator instead of the stock aluminum part. Not only is there more cooling capacity, but it costs less too.
But other parts that you might want to investigate are the fan clutch (often a problem), the thermostat, and the water pump (look for seeping from the vent hole). You might be experienceing any one or more of these problems.
Just replaced my fan clutch recently and I must say that out of the ten or so cruisers I've looked at none of the fan clutches made the usual sound on initial startup. Now when I start the truck cold you can definitely hear the fan for severla seconds. If you do not hear this I would imagine that the fan clutch may not be working properly but this is just a guess.
Ron Davis Racing did the one in my AZ SC 80. Perfect fit, excellent workmanship and it uses the OEM cap.
I found the Hayden fan clutch did a better job cooling then the OEM blue in my 80.
Also how old is your anti-freeze?
Welcome to the forum
I found the Hayden fan clutch did a better job cooling then the OEM blue in my 80.
Also how old is your anti-freeze?
Welcome to the forum
>> and fix the problem with an Al radirator and assessory fans. <<
Clark,
As others requested, it will help if you will give us more information on your truck; miles, Supercharged?, prior cooling system maint, what you've already tried, etc.
As for the '97 FZJ80 we know the following:
* If the stock cooling system is performing as designed then it will work great even in your extreme AZ summer climate.
* A non-functioning cooling system can be caused by many things; bad fan clutch, slipping belts, clogged radiator, stuck thermostat, failed HG, etc.
* An engine with forced induction needs a perfect cooling system and some S/C engines need additional help.
* The A/C cutoff is 226 degrees which is very close to the "red" on the OEM temp guage. That is way too hot for you to be driving it like that for extended periods of time.
Assuming your truck is stock, your cheapest option is to get the cooling system operating properly:
* Test for bubbles in the coolant (possible HG failure)
* Make sure you are using a good quality coolant mixed 50/50 with distilled water
* Make sure the belts are working; use only OEM belts
* Make sure the fan clutch is working; (testing procedure in the archives)
* Make sure the thermostat is working and positioned properly
* Make sure the radiator cap is working
* Make sure there are no cooling system leaks (internal or external)
* Make sure the radiator is not clogged (may have to use a temp gun)
We seldom see problems with the water pump but it's a component and if everything else checks out OK then the wp is a possibility.
Keep us posted.
-B-
Clark,
As others requested, it will help if you will give us more information on your truck; miles, Supercharged?, prior cooling system maint, what you've already tried, etc.
As for the '97 FZJ80 we know the following:
* If the stock cooling system is performing as designed then it will work great even in your extreme AZ summer climate.
* A non-functioning cooling system can be caused by many things; bad fan clutch, slipping belts, clogged radiator, stuck thermostat, failed HG, etc.
* An engine with forced induction needs a perfect cooling system and some S/C engines need additional help.
* The A/C cutoff is 226 degrees which is very close to the "red" on the OEM temp guage. That is way too hot for you to be driving it like that for extended periods of time.
Assuming your truck is stock, your cheapest option is to get the cooling system operating properly:
* Test for bubbles in the coolant (possible HG failure)
* Make sure you are using a good quality coolant mixed 50/50 with distilled water
* Make sure the belts are working; use only OEM belts
* Make sure the fan clutch is working; (testing procedure in the archives)
* Make sure the thermostat is working and positioned properly
* Make sure the radiator cap is working
* Make sure there are no cooling system leaks (internal or external)
* Make sure the radiator is not clogged (may have to use a temp gun)
We seldom see problems with the water pump but it's a component and if everything else checks out OK then the wp is a possibility.
Keep us posted.
-B-
- Thread starter
- #8
Thanks for the replies
It is a 97 with 85K mi and 33mtr's.
I haven't tried much, I should probably start with the fan clutch. The car is well maintained, running mobil 1 every 3k and 50/50 coolant changed every year. (normal interval maint done at dealer) This problem just started this summer, on hot days mainly when going out of town, in town driving didn't seem to bother it. I was wanting to SC the truck but with the cooling problem I wasn't sure if it was a good idea in AZ. I wanted to put a Fluidyne radiator in but they don't make one for the 80. Does anyone know of a full Al radiator (ie racing style hp radiator for 80's? Also what is the consenses with going electric with fans.
I will have to check the fan clutch when I get a chance.
Thanks for the help and the Welcome...I have been on the Lcool80's list for awhile but just found this forum.
It is a 97 with 85K mi and 33mtr's.
I haven't tried much, I should probably start with the fan clutch. The car is well maintained, running mobil 1 every 3k and 50/50 coolant changed every year. (normal interval maint done at dealer) This problem just started this summer, on hot days mainly when going out of town, in town driving didn't seem to bother it. I was wanting to SC the truck but with the cooling problem I wasn't sure if it was a good idea in AZ. I wanted to put a Fluidyne radiator in but they don't make one for the 80. Does anyone know of a full Al radiator (ie racing style hp radiator for 80's? Also what is the consenses with going electric with fans.
I will have to check the fan clutch when I get a chance.
Thanks for the help and the Welcome...I have been on the Lcool80's list for awhile but just found this forum.
clarkrw3 said:
Ron Davis Racing
Scamper said:
This is not an arguement, just a question, but does the brass radiator really have more cooling capacity??? How much more, and how do you measure that...in other words, same volume, same flow rate due to the thermostat and the water pump, etc, what gives it more cooling capacity??? Are we just assuming more conductivity with Brass vs. Aluminum and Plastic??? Again, not an arguement, just a curiosity based on the fact that I thought the brass radiator was better for reliability and not necessarily for cooling capacity. Thanks. Has anyone taken a before and after measurement with the Aluminum vs. Brass rad, all other things ( thermostat, water pump, coolant ) being equal??? Thanks.
turbocruiser said:
I replaced mine with the brass one, I believe it has three rows vs two in the aluminum one,
and it was cheaper than the one for the 96??
Eduardo96FZJ80 said:I replaced mine with the brass one, I believe it has three rows vs two in the aluminum one,
and it was cheaper than the one for the 96??
That's basically what I was going on. I don't know of any scientific basis for claiming more cooling capacity, other than the fact that if you expose more coolant to the airflow, you'll get more heat exchange, other things being equal.
clarkrw3, I experienced much the same as you. I replaced the rad with the 3 row brass job, put in a new fan clutch and a new thermostat. I cannot get the beast hot even with the AC on full cold, and pulling a 3500lb boat up a steep mountain grade with the pedal to the metal and SC to boot. As well as turning 35s and lots of extra weight inside and in mods. The only thing heating up is my gas bill. I would seriously look at a new rad etc. and flush it every one to two years. If different coolants have been mixed in the system, I have little doubt the rad will have the dreaded sludge build-up. The sludge may not be apparent from a visual inspection.
Cheers,
Sean
Cheers,
Sean
Scamper said:
Okay, cool, I always assumed the advantages of the Brass Rad were:
1. Less likely to leak at the top.
2. Less aluminum for the coolant to attack.
3. Less plastic.
4. Less expensive.
5. Easier to repair from trail fawkups perhaps?
6. Easier way to really get rid of rad sludge perhaps?
Which are all wonderful reasons alone to get the Brass Rad. When the extra cooling capacity was mentioned I really perked up and started to wonder whether the Brass Rad would also improve performance? Not necessarily performance in the sense of power perhaps, but performance in the sense of how hard and how long you can work the motor, OR, performance in the sense of making it significantly safer to work the motor without predetonating or whatever. If that is the case, I want one now and not later when or if my original rad starts leaking! I agree that in theory a three row will cool more than a two row all things equal, and I wonder which material transfers the heat faster from the coolant to the air? Really I'm just wondering if anyone could roughly say that brass rad lowered temps by X degrees or whatever??? Thanks, this is cool.
turbocruiser,
The brass radiator has 3 tubes; the aluminum radiator has 2 larger tubes. Somewhere in my files I have the diameters of the two different types of tubes. I am pretty sure Christo or Robbie measured and posted them at one time. I doubt there is a significant difference between the cooling "capacity" or efficiency of the two OEM radiator styles. #4 would be the reason that I would use the 3-core when my '97 radiator needs to be replaced.
-B-
The brass radiator has 3 tubes; the aluminum radiator has 2 larger tubes. Somewhere in my files I have the diameters of the two different types of tubes. I am pretty sure Christo or Robbie measured and posted them at one time. I doubt there is a significant difference between the cooling "capacity" or efficiency of the two OEM radiator styles. #4 would be the reason that I would use the 3-core when my '97 radiator needs to be replaced.
-B-
Beowulf said:
Cool, thanks B, #4 is reason enough for sure!!!
Turbocruiser,
The physics of the thing work a little like this. When comparing a brass /copper rad to an aluminum you need to look at the construction of the core and the fin spacing. Typically a brass rad has small tubes, like 1/4" to 1/8" that the water flows through while an aluminum rad allows the use of a larger tube that is generally 1" to 1 1/2". This is usually why an aluminum rad cools better than a brass copper. However, it depends on the particular unit and the application.
The other issue is fin spacing. AG Bell's book "4-stroke performance tuning" says that a radiator designed for the track (and hi-speed cooling) like the aluminum race radiator you are asking about has fewer fins per inch than a street rad, which is designed for low-speed cooling. It says the optimal fins/inch is lower for hi-speed because too-high fins/inch offers such hi resistance to airflow that air tends to pile up in front of the rad and flow around rather than through the rad.
The aluminum units can be quite a bit lighter than the brass ones and typically cost more as well.
Admittedly, I haven't paid any attention to the specs of both variations of the OEM LC radiators, but I bet -B- or C-Dan could get that info for you. However, from the guys that have tried both, it sounds like the brass one may work the best for us. I've not had any issues with my OEM aluminum one even though my rig is supercharged. However, if it does ever crap out on me, I'll replace it with the brass one based on others experience.
If your turbo is watercooled, obviously your cooling system will be taxed more heavily than mine will with the SC so if makes sense that you pay close attention to it. I've had some experience with trying to keep watercooled turbo systems cool in the past and if your radiator alone does not solve things for you, I might have a few other ideas you can try.
Mike
The physics of the thing work a little like this. When comparing a brass /copper rad to an aluminum you need to look at the construction of the core and the fin spacing. Typically a brass rad has small tubes, like 1/4" to 1/8" that the water flows through while an aluminum rad allows the use of a larger tube that is generally 1" to 1 1/2". This is usually why an aluminum rad cools better than a brass copper. However, it depends on the particular unit and the application.
The other issue is fin spacing. AG Bell's book "4-stroke performance tuning" says that a radiator designed for the track (and hi-speed cooling) like the aluminum race radiator you are asking about has fewer fins per inch than a street rad, which is designed for low-speed cooling. It says the optimal fins/inch is lower for hi-speed because too-high fins/inch offers such hi resistance to airflow that air tends to pile up in front of the rad and flow around rather than through the rad.
The aluminum units can be quite a bit lighter than the brass ones and typically cost more as well.
Admittedly, I haven't paid any attention to the specs of both variations of the OEM LC radiators, but I bet -B- or C-Dan could get that info for you. However, from the guys that have tried both, it sounds like the brass one may work the best for us. I've not had any issues with my OEM aluminum one even though my rig is supercharged. However, if it does ever crap out on me, I'll replace it with the brass one based on others experience.
If your turbo is watercooled, obviously your cooling system will be taxed more heavily than mine will with the SC so if makes sense that you pay close attention to it. I've had some experience with trying to keep watercooled turbo systems cool in the past and if your radiator alone does not solve things for you, I might have a few other ideas you can try.
Mike
mts said:
Wow Mike, thanks for that response, super cool ( pun, haha ) of you to take the time. The turbo is both water and oil cooled so that is one reason I want the highest cooling capacity possible. On the one hand the fact that the turbo is water cooled would seem to stress the cooling system somewhat but the fact that the safari system comes with this massive oil cooler and tranny fluid cooler probably pulls as much if not more heat out of what the stock system handles anyway? Not sure about that. I have no problem with my original rad; it does not leak or sweat or anything and my temp needle never, absolutely never gets even as far as level as in halfway up ... it is constantly about one needle's width lower than level on the gauge and it does not seem to matter the outside temp or anything - so far nothing I have done has even momentarily increased the temp according to the gauge ( I know its not that accurate but it seriously stays steady no matter what, unless warming up of course.) So, I guess I've concluded that if my rad starts leaking or something then I'll switch to the brass rad. Thanks again everyone for the responses.
turbocruiser said:I have no problem with my original rad; it does not leak or sweat or anything and my temp needle never, absolutely never gets even as far as level as in halfway up ... it is constantly about one needle's width lower than level on the gauge and it does not seem to matter the outside temp or anything - so far nothing I have done has even momentarily increased the temp according to the gauge ( I know its not that accurate but it seriously stays steady no matter what, unless warming up of course.) So, I guess I've concluded that if my rad starts leaking or something then I'll switch to the brass rad. Thanks again everyone for the responses.
Turbocruiser,
Sounds like you might have fun adding an aftermarket coolant gauge to your rig. I think you may be surprised. The OEM gauge is not linear and has a big "dead spot" in it when the truck is operating in a "safe range". But its fairly large range. If the gauge moves out of that dead spot at all, you've got a problem.....the temps will have climbed significantly before the needle on the gauge moves enough to notice. It's not just the LC gauge that's like that, most/all OEM gauges function that way. If you think about it, that's really the absolute best way to have it set up from the factory. But, when you start modding something, turbos, SC, different cooling mods, etc., the only real way to tell if the truck is running consistently warmer/cooler before/after the mod is to either linearize the OEM gauge with resistors or get an aftermarket one.
Your gauge doesn't move from the "dead spot" so you've got no issues, but if you are anything like me and you like to tinker with things a bit, it's nice to know the before/after results with a bit more precision and know if you are on the "edge" of the safe range on in the middle.
Mike
Turbocruiser,
I agree with Mike's suggestion that you play with a linear aftermarket temp gauge and I can confirm that the OEM gauge will not move while the linear gauge will continue to move through a wide temperature range. The range of the flat spot has been documented in the past (Photoman & Rich).
At Photoman's suggestion I installed a Greddy 60mm temp gauge with warning LED and peak memory. It's calibrated in Centigrade but that's not a problem.
(edited the correct gauge size 60mm, not 50mm)
-B-
I agree with Mike's suggestion that you play with a linear aftermarket temp gauge and I can confirm that the OEM gauge will not move while the linear gauge will continue to move through a wide temperature range. The range of the flat spot has been documented in the past (Photoman & Rich).
At Photoman's suggestion I installed a Greddy 60mm temp gauge with warning LED and peak memory. It's calibrated in Centigrade but that's not a problem.
(edited the correct gauge size 60mm, not 50mm)
-B-
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