LUVTruck.com

I think I need to work on my truck's cooling system. I had to haul a whopping 2 pieces of plywood yesterday and the engine started getting a little warm, going up the smallest of hills. It never got too hot and I guess was in the normal temperature range, but I am concerned that I don't have any reserve cooling capacity if needed. I've noticed that driving at speed is OK, but idling allows the engine to heat up quite a bit.

My engine is stock with the original radiator and mechanical fan. From reading other posts on this site, I see that some with big motors have put in electric pusher fans and aluminum radiators. I would like to know if a pusher fan is helpful on the stock setup as well. I will keep the mechanical fan (might do a flex fan later). In addition to having the radiator boiled out if needed, getting the proper coolant mix, radiator cap so coolant doesn't boil, etc.

I would find/fix a cooling problem before adding more parts.

It ran cool without the extra fan when it was new, and it's whole life untill now. I would think there is a problem somewhere.

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OK, I'm over it. Where's the beer?

another big help is to add an overflow tank.... they should of come with them but didnt

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My old but now gone Luv...

Do you have a fan shroud? I have a spare onr from a 72 if needed.

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Certified pilots, looking down on people since 1903.

I scrounged around a wreckers armed with my radiator dimensions. Found a nice core from I think a Toyota 6 cylinder truck, maybe it was Nissan, but a 6 and not a 4. Anyway, about 2" taller maybe, a wee bit wider. Now mine runs real cool even in high desert temps with a load on, the truck, not me. It was cheap, like 20 bucks? While you're at it check that upper and lower hoses wil match up. Saves a lot of jing.

Have got the stock fan shroud on there. I think I will add a coolant overflow tank. Any recs on one that fits well?

I guess my question was: is the stock LUV cooling known to be

a) More than adequate
b) Adequate
c) Barely adequate
d) Not adequate.

If it is b,c, or d regardless of the condition of the system I was going to add a pusher to help survive traffic jams in 105 degree ambient temps. Of course, I think right now a good flush and coolant change with a new radiator cap and thermostat is in order.

I do like the idea of getting a bigger radiator core though.

well i have a new stock rad with a hopped up G180 motor and even when it 100 here it runs right where it is supposed to run so i would say it is
a) More than adequate

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My old but now gone Luv...

i was running the stock radiator on my truck with a v6 6in lift 33,s through two feet of snow and highway speeds during the summer and it worked fine so i would say more than adequate also.
if a pre existing repair on it was done better it wouldnt have given out a few weeks ago lol

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No luv right now =(

Right-O, as the English say. Time to get to work. I haven't had my LUV that long, but from what I have seen the thing seems in general well engineered. Glad to hear the cooling system is good on them too.

If anything...Luvs tend to run a bit on the cold side. I suggest you pull your radiator, flip it upside down, and flush out all of the garbage in it with a hose. Then stick a hose on full blast in the top opening (after you install it back in your truck and hook up your hoses - duh...lol), open up the petcock, and flush out your block and heater core with the engine running and the heater on to get the rust and garbage out of them too.

If your head gasket, intake gasket, water pump, fan belt, hoses, heater core, radiator cap, and thermostat are all good, and your radiator isn't plugged up, leaking, or all covered with bugs, crud, dented fins, etc., then you should be fine.

My truck was running too hot and I recently found it had the small 14" 4 blade fan and should have the 15" 7 blade (auto trans with AC).
I couldn't find a stock 15" fan and was in Reno recently so I purchased an after market fan from Summit Racing. It cost about 20 bucks.
This fan:
https://www.shopatron.com/product/part_ ... 9594.0.0.0
It looks like this:
http://www.flex-a-lite.com/auto/assets/ ... conomy.gif

Flexalite also makes adapters that fit the huge 1 1/4" hub on the LUV/isuzu waterpump:
https://www.shopatron.com/product/part_number=840/694.0
https://www.shopatron.com/product/part_ ... 9598.0.0.0
https://www.shopatron.com/product/part_ ... 9598.0.0.0

I cut the blades off my old 4 blade fan and used it as a mount for the flexalite 15" fan. I should have it installed this weekend, I'm hoping it will help my truck run a bit cooler...

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79 Black Mikado longbed with AT & AC...

First off: I discovered I have been spoiled by the cooling system on my other truck (82 GMC Full size 3/4 ton). That truck runs at the thermostat temp (180 degrees) no matter what I do or when. Huge radiator, clutch fan, yada yada yada. From reading the meaning of where the temp needle points in the LUV service manual, I must have a 160 degree thermostat and the temp has never gotten much hotter than 195. No problem. Anyway:

I have decided what I am going to do (and the approximate order).

1) Add a coolant overflow bottle. Bad things happen when air gets inside a cooling system (the Dexcool saga, anyone?) not to mention that it gets hotter. And that sometimes you spray coolant everywhere without one.
2) Put in 180 degree thermostat. I don't think 160 will give me anything except a low oil temperature. Especially since most of my trips are short. All new cars run at this minimum temp. (I know there's quite a debate out there on 160 vs 180 for old cars/hot rods...but I have decided to run all my engines with 180 thermostats).
3) New radiator cap.
4). Flush all old coolant out. Leave it with just clean water.
5). Clean radiator. Either with Prestone Super Radiator Cleaner (liquid) or the powdered one. Found out about the powdered one on a Corvette site where they use it to flush the brown Dexcool gunk out. You have to get it at the dealer or get the chemicals separately.
6). Flush cleaning solution out until it's just clean water.
7). Drain enough water to put enough coolant in to make 50/50 mix.
8. New radiator cap (because the seal of the other one can get crapped up during the cleaning procedure).
9). Leave it alone and be happy. The LUV is known to have a properly engineered cooling system.

Tell me about the Dexcool saga? Is this a problem with the dexcool antifreeze? I have used it before, but didn't have a problem, but maybe i was lucky.

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75 Luv, 350 V8, TH350, Camaro rearend. New 1975 Luv Step side. Stock for now.
Grandmaster of the "Shade Tree" way.. I can't see the yard for all the cars. Come on down and we will sit on the porch and watch the grass grow.

From what I have read on the internets, mid '90s-early '00 GM vehicles present problems of heater blows cold air, heater inoperative, engine overheating and when you open up the radiator it's filled with brown sludge and rust. They say that what happens is that people let their coolant get low, and apparently Dexcool and air are reactive, meaning that it forms the brown sludge and starts to break down when air gets into the system. They made a new antifreeze formulation; slightly different than traditional antifreeze. I looked at the datasheets and Dexcool is mostly ethylene glycol (just like the green antifreeze) but I guess it's different in some special way. Besides being orange. Anyway I guess if you use the powdered oxalic acid radiator cleaner (Used to be Prestone AS100, can't buy it at Kragen any more and it's a nasty chemical anyway) you can clean out the sludge.

If you have a Dexcool car, they say you have to keep the coolant as full as possible so air can't get in. I'm not sure about any other damage it may have caused (such as with plastic intake manifolds on some cars), but people are getting money out of GM for their troubles. It does suck that some people have had to pay tons of money at the dealer because of the problems with Dexcool. It seems like an honest technological mistake to me; I get the picture though that some people think GM did it on purpose. Lastly; I bet it's hard to make a coolant that would really have a 100000 mile service interval without, well, testing it first and I suppose they have; it failed in that respect. Would probably work fine if you changed it like you do regular antifreeze.

I wouldn't want to run it that long. But if your dog drinks some, it is not supposed to hurt them. I wasn't putting it in new cars, just because of how it doesn't react with aluminum. It is hard to get VW antifreeze for my vanagon where I live... It is expensive too. I have not used GM Dex-cool, it was like Valvone or another brand from a FLAPs.

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75 Luv, 350 V8, TH350, Camaro rearend. New 1975 Luv Step side. Stock for now.
Grandmaster of the "Shade Tree" way.. I can't see the yard for all the cars. Come on down and we will sit on the porch and watch the grass grow.

Changed the thermostat today and discovered there was a 180 degree unit already in there. So it appears my temperature gauge isn't reading correctly, it's reading about 20 degrees low according to the manual (hence why I thought I had a 160 degree thermostat in). The gas gauge reads low as well, which to me sounds like the voltage going to the gauges is out of spec. Since it's just some resistances in series, if you aren't applying the right voltage, you won't get the right readings. I'll check into that later. Also put in an overflow tank about 2 weeks ago. Coolant looks good, isn't rusty and stuff, so I'm not going to do a flush right away. But hey, I found the part that Kragen doesn't have to order for me--the radiator cap! It was right there on the shelf. They had to order the thermostat and gasket for the thermostat. Seems like they carry a very low number of parts in stock, something we all have to deal with I'm sure.