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Discussion Starter #1
Okay I`ll give the break down.
New 3 rowe radiator, new hoses, 180 thermostat, new thermal clutch unit with 7 blade fan. New water pump with flow kooler impeller, 30% anti freeze the rest water and red line water wetter, The whole cooling system is intact and operational. The engine is a mild SBC 350 in a 86 Olds cutlass. A few weeks ago I replaced the radiator to the 3 rowe, the car would run a maximum of 190 degree`s on the hottest days and on the interstate, with the old radiator which was a 2 rowe, it always ran 220 on the interstate around 70 MPH. Over the past week, I reinstalled the A/C, had it charged, but it developed a leak and the freon leaked out, when I did this I had to get another radiator hose, which fits a 86 caprice. the hose is smaller in diameter and has more bends, I also changed pulley`s when I reinstalled the Air, I went to the complete 305 pulley arrangement also off a 86 Caprice, now around town the car runs around 190 to 200, on the interstate it goes to 220 rather fast and stays there, the timing is on the money, as is the carb, I don`t know what else to look at as everything has been replaced, I`m positive there is no blown head gaskets or cracked heads, while on the interstate, I can place the car in neutral, let it just coast down a small hill no longer than a 1/8th of a mile, then place it back in drive and the temp will go back down to about 205, then it`ll climb right back to 220 within a mile when I get back on the throttle, I realize 220 isn`t considered running hot, but it`s too hot for my comfort, I want it to run around 190 like it used to, I don`t see how doing the small changes I did to the system should make it run at this temp, before I set a match to this thing does anyone have any ideas? I`m sick of it acting like this, it`s did this ever since I reinstalled the A/C, but even when the A/C is NOT in use it still runs 220 just as if the Air was left on. It acts as if the condensor is staying hot all the time. Out of ideas, any help is appreciated.
 

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Pulleys

Doc here :pimp:

About the only thing I can think of would be, did you measure the diameter of the pulleys? Could they be turning slower, in effect turning the pump slower than stock?

Everything else sounds right to me...

Doc
 

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Member# 3287
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I think Doc has the answer, re the water pump turning over slower now.
 

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I'm kind of thinking along the lines as Wrencher. Where is the condenser mounted? Front of the radiator, back, is it blocking the airflow (etc.)?
 

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Discussion Starter #8
Best of my knowledge, it`s the factory condensor, and it`s mounted in front of the radiator, I checked the fins out several times, and it seems there clear, but I`m thinking it still needs replaced, since I have`nt had a leak detector ran on it to see where the freon leaked out. It does seem like it`s a air flow problem since when I let off the gas and let it coast it cools off, I`ve checked everything in the front end, the air dam is okay as are the flow directors in front of the condensor. As for the pulley`s, it does appear as if the water pump pulley is slightly larger which would slow it down, but with it on the car it`s hard to tell, the crank pulley which was on it, was also a 3 rowe, the front pulley that ran the water pump and alternator was larger than the 2 behind it, the 305 crank pulley has all 3 pulley`s the same size which is the same size as the first pulley on the 350 crank pulley. It may just be I have to live with it running 220, even so I don`t like it to run that hot, I noticed anytime it climbed a slight incline, the temp would go up, but it also on level ground if I sped up to around 75 to 80 mph it would cool off some, I noticed if I ran the heater full blast it would cool if off slightly. But I`m still out of ideas as far as getting it to run any cooler, the last thing I`ve did is drain some of the coolant which had a lot of green in it and replaced it with water and water wetter, so I`m yet to try it like this. I did a experiment with it earlier, I had the radiator cap on, but not all the way, and letting it idle like that for 20 minutes it never got over 180, after the thermostat would open, it would cool down to around 170, but then I put the cap on all the way and pressure builds up, it`ll idle at 195 - 200. The cap is the only thing I haven`t replaced, but it`s only a few years old and the car has little miles on it since it was replaced. I am using the factory fan shroud, and it`s in good shape, when I changed all this over to have A/C was when the problem resurfaced, so my only conclusion is there`s either something up with the condensor or the pulley`s were slowed down enough to make it run hotter, 220 isn`t too bad at 70 mph, but it`s still higher than I perfer it to run, anything over 200 makes me nervous, thanks for the help all, but I`m still at the drawing board.
 

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Race it, Don't rice it!
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Temp increases while under a load almost always means lack of water volume. Temp decrease with heater on almost always means lack of air flow or usable core space. Assuming no restricton in the block water passages and a clean rad. You might try a smaller rad. Like a two core with 15 to 17 fins per inch. To many fins will not allow air to easily move through the core at higher speeds. Stacking of the air ahead of rad. is the cause. A bad finish on the cylinder wall can cause higher than normal temps as well. Not much you can do there.
 
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