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My 85 is finally running but has some issues

 
Old 01-21-2019, 11:53 PM
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Miket440
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Default My 85 is finally running but has some issues

My cars been sitting for quite a while. I recently got it started again and I am trying to get her back on the road. After replacing a lot of worn out parts she starts and runs pretty good but has some problems. The biggest problem is the cooling fan does not come on and the car starts overheating. I disconnected the low pressure AC switch and it will come on, I jumper A and B and it will come on. I assume that means the relays and fusible links are good? I changed out the temp sensor but no change. I would think the car wouldn't run to good if that was bad but I changed it anyways. Any Ideas where I go now? Not sure it matters but my car has an AUX fan.
Another problem is the AC clutch doesn't engage when I turn on AC. I assume that's why the cooling fan doesn't turn on when the AC is turned on. I think this means a low refrigerant charge, but I guess Ill deal with that latter.
Also, there seems to have a slight off idle stumble. Idles great, give more throttle and it clears right up. Vacuum leak?
Any insight on these issues is greatly appreciated.

Last edited by Miket440; 01-21-2019 at 11:54 PM.
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Old 01-22-2019, 03:18 PM
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Kevova
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Fan doesn't come on until 226 or so. How hot are you allowing engine to get? Run rough...I would add BG 44K to fuel and drive it for 100-250 miles see if it clears up. It could be stale fuel from sitting.
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Old 01-23-2019, 01:01 AM
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xrav22
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Do you have pressure on your top radiator hose after 195 , water pump could be bad. Make sure it is full of water.
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Old 01-23-2019, 08:40 PM
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Miket440
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Originally Posted by Kevova View Post
Fan doesn't come on until 226 or so. How hot are you allowing engine to get? Run rough...I would add BG 44K to fuel and drive it for 100-250 miles see if it clears up. It could be stale fuel from sitting.
I let the temp get to 235 according to gauge on dash and no fans and I can hear water boiling into overflow. No coolant leaks anywhere I can see though. Never heard of BG 44k but ill try and find some. All old gas was removed before starting it.

Originally Posted by xrav22 View Post
Do you have pressure on your top radiator hose after 195 , water pump could be bad. Make sure it is full of water.
I replaced the water pump, hoses and thermostat before starting it, ill try feeling the top hose to see if its hot. How do I make sure the water pump is full of water? I would assume it is since the dash gauge gets temp from side of block?
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Old 01-23-2019, 10:11 PM
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Does engine run hot driving over 40 mph? Do you have manuals?
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Old 01-23-2019, 10:20 PM
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Hot Rod Roy
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After the engine cools off, is your radiator still full? You may need to run it, then check it several times to be sure the cooling system is full. The "boiling" you hear may be the steam being pushed thru the radiator cap due to the system not being full. If your rad cap is good, the radiator should stay full, as the coolant will be pulled back into the radiator from the reservoir as the engine cools off.

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Old 01-23-2019, 10:47 PM
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xrav22
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When the gauge gets to 228 , the large fan should come on, no matter what is going on. I would clean the pins on the computer after sitting a long time.I know mine were corroded. This is strange mabey this helps
Note. Now that I have a look the ground G103 may be dirty I cant remember where it is , I think under the battery. The ECM would need to ground the fan for it to come on at 228.
Good Lck


Last edited by xrav22; 01-23-2019 at 11:03 PM.
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Old 01-30-2019, 06:32 PM
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Miket440
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Thanks for the suggestions guys. After pulling my hair out trying to figure why the fan wasn't coming on I went at it one last time. I cleaned as many grounds up as I could find, I changed out the autozone CTS I put in for an ACdelco one and made sure the radiator was full. Low and behold the fan came on at 225. I decided to take her for a drive for the first time in about 15 years. For the most part, the engine runs strong and idles good. The old tires have flat spots and wobbles a bit. Brakes seem good. The A/C dosent come on, I think its low on freon, I am sure I wont find any r12 any place. When I got back from driving around the block I see the new steering rack is leaking from somewhere. The biggest issue is when I turn it off while the cooling fan is running or just before the cooling fan would come on around 220 degrees the radiator boils into the overflow a lot! After I let it cool down it seems the radiator is full. The cap is a brand new stant 16lb. Could I have a head gasket leak? How could I tell?Should the fan stay on after I shut the car off? Been so long since I drove it last, I cant remember if it did.
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Old 01-30-2019, 08:31 PM
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xrav22
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I was driving home from Las Vegas and Had temprature spiking /changes when I leaked out water. Steaming and boiling also. Open the coolant when it is cold ,start the car, and when you see the thermostat open(fluid rushing) fill her up and put the cap on.
Water will rise then go down after thermo opens. That has always done it for the 85.

Last edited by xrav22; 01-30-2019 at 08:33 PM.
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Old 02-03-2019, 01:29 PM
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Miket440
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After trying different radiator caps including a ACdelco, Stant. I found they did not seal against the lower sealing surface of the filler neck. Coolant was able to simply flow into the overflow from the radiator even cold. This was a radiator I bought from Napa. I figured I would file some of the top of the filler neck down 1/16" Sure enough no boiling over anymore.
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Old 02-03-2019, 05:35 PM
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Hot Rod Roy
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Originally Posted by Miket440 View Post
Should the fan stay on after I shut the car off? Been so long since I drove it last, I cant remember if it did.
If you'll look at the diagram xrav22 posted for you (#7), you'll see that the power to the relay is only applied when the ignition is on. That means the radiator fan will turn off when you turn off the ignition.

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