87gtaredonred

Hey guys, I have a bone stock 87 gta 5.7. I have a 180 thermostat, normal driving It hold temp just fine, if I get caught in traffic for a length of time the temp creeps up to 220 the fan cuts on and maintains that temp. To me seems alittle hot is that normal, Ive never noticed that with my other fbodies.

dlinger

iTrader: (4)

Normal for electric fan operation. Same in 84 L69 with single fans and 95 LT-1 dual fans unless AC is on.

I was nervous until I talked to my friend who was a GM tech. He told me it was designed to work that way so don't worry about it. I still watch gauge close when idling, as we all should.

I don't know how true it is, but I read where the oil needs to get up to designed temp to burn off condensation. I remember years ago, you could always tell a city driven car with a milky residue on the oil cap.

I guess I should ask, when it reaches 220 and fans come on, does it cool down? How about when you start driving moving the air through the radiator?

89 formula TPI

I am really glad to hear I am not the only one with this concern because my 89 dual fan formula does the exact same thing. I actually posted this exact question yesterday lol. It worries me bc If the fan should fail I'm screwed. I think most cars nowadays always have a fan running so u don't see the temp fluctuate. General concensus always seems to be GM designed them to run hot on purpose but it still makes me worry

87gtaredonred

I actually replied to your question lol, i went ahead and posted one also. Just for fun i bought a new raditor yesterday just to see if it makes any difference

89 formula TPI

I just saw that haha I was going to edit my reply lol. Curious how the new radiator works. Is it stock? Let me know if see any improvement!

87gtaredonred

Yes sir stock replacement from advance auto, i ran into a guy over the weekend with a stock iroc he said his holds pretty steady temp and thats the radiator he had. Im putting it in this weekend ill let u know. Thinking about the lower fan temp switch also

89 formula TPI

Good luck! Dying to hear your results as I have been wondering about this since I did my cooling system maintenance last summer. (Tstat, coolant flush, radiator cap, water pump) also bought the secondary aux temp fan switch for under the passenger manifold but could not get to it.

87gtaredonred

Well maybe a small update, I exchanged numbers with the guy with the iroc I ran into, I ask him yesterday if he had a dual fan setup, he said yea I do but 1 fan is wired to always run, well duhhhh no wonder his temp never creeps up lol. I ordered a 195 fan switch for my car last night so in theory my fan should cut on now when sitting in traffic. Hopefully ill have it in and can do it and my radiator this weekend. Ill let you know how things work out

brettr81

Actually, with cast iron heads, theoretically, you want the engine at around 220 to maximize combustion. That is what I've read everywhere. Anything cooler and you're not getting the most out of your gas money. For some reason most people on here think their car should run at 180. I believe with aluminum heads you want them to run cooler though.

87gtaredonred

Yes sir, as u said theoretically your right my car seems to suffer if it sits at 220 to long I can tell the performance really drops. I drove it to the coast over the weekend big cruise in down there, got caught in traffic for over an hour it didn't over heat but the temp stayed at 220 till I got out of traffic and it felt like I was dragging a boat anchor behind my car lol.

dlinger

iTrader: (4)

Do you have a dual fan? If so are both coming on?

My 95 one fan will come on (not sure of temp as I can't always hear it) and when it hits around 220 the second fan comes on. However it will cool it some. On our 84 single fan it too comes on around 220 but it again cools it down. Not as much as air movement through the radiator does.

New radiator may help if old is getting plugged up, maybe fans cannot cool it adequately.

I guess I have driven too may GM vehicles with electric fans. 04 and 05 impala, 92 corsica, 84 cavalier. None of them had the fan running all the time. My Impala's with aluminum heads are basically same fan operation as my 95 camaro. One fan on when car is not moving and car is heating up. Second fan on when temp gets 210-220. Unless AC is on then second fan comes on quicker. Fans will cool car while not moving though. You can watch it move down and then back up when fan shuts off. Once you start moving over 45 mph, temps drop down to 190 or so (thermostat temp).

87gtaredonred

Yes sir I have a dual fan setup both are working, the first one cuts on at 220 and it usually will cool it off alittle, but both fans are working the other one kicks in at around 240 thank god it didn't need to come on the other day, last wendesday when it done it it was like 95 at the coast and I had be driving 4 hrs already and for the last hour it just sat there in traffic so it was heat soaked pretty good, it hit 220 and stayed there till I got out of traffic but you could really tell the car was suffering at that point lol

89 formula TPI

That is definitely good to know. I was wondering how the iroc could stay at 195 with no fans at idle.

I was reading through the later comments. It sounded like max combustion at 220 was supposws to be a good thing by the way he phrased it, but I agree with u my car feels sluggish when it gets that warm compared to when it's cooler

89 formula TPI

Any luck replacing the radiator? Curious if that changed anything although from what I'm hearing from everyone it shouldnt.

87gtaredonred

I sent you a pm, let me know if you got it?

Ron U.S.M.C.

I read this thread and maybe I missed the part about actually replacing the stock fan switch to one that comes on much earlier.
The fan switch "on and off" temperature and the thermostat work together.

A new radiator is a good idea but if you do not install a lower temperature fan switch I think your going to be disappointed.

87gtaredonred

Yes you are correct, i swapped the raditor seems to cool about the same strange but the ac does seem to work better but thats a different story lol. I installed a 195 temp switch that thing is great i drove the car let it warm up and parked it in about 5 minutes fan came on i let it sit like that for 30 minutes temp guage never moved. I shut the car off let it sit like 10 minutes to heat soak it fired right up. My original problem was if i got caught in traffic it would get to 220 the fans would kick on but was still heat soaking everything so bad car ran like crap till u cooled it back off especially if you shut it down gave it a few minutes to heat soak you could tell it was just to hot ��

Ron U.S.M.C.

So you fixed it.
Nice job.

Having a nice new radiator, fan switch with a lower "on" and "off" setting and the 180* thermostat is really nice.
Just the switch and thermostat is what I always suggest to anyone complaining about there car running to hot for them.

LiquidBlue

Couple things to rea search. Is temp gauge accurate and 220 ok for engine. 220 won't boil at higher pressure, so if the system is sealed and under pressure you shouldn't have issues with boiling. Radiator cap is important