Mechanics

OVERHEATING

1984 Honda Civic

Engine Cooling problem
1984 Honda Civic 4 cyl Front Wheel Drive Automatic 337700 miles

Having problem with overheating, replaced thermostast and radiator cap, but still overheats. I don't see any coolant leaks (except when it overheats), no coolant on passanger floorboard either. When thermostat is removed, there is no overheating, but again no heat in passenger compartment either.
Also, just replaced starter and alternator (voltage regulator went out in the old one) and did an oil change.
And now, besides the overheating, when I go to start it first thing in the morning it doesn't want to turn over and acts like the battery is going dead (but the battery is only 4 or 5 months old) and
it seems to be " loading up" overnight-once it starts it blows lots of dark grayish smoke, but does not smoke while driving. Any suggestions?
Avatar
Lorinsmonkey
March 24, 2009.



Hi lorinsmonkey,

Does the radiator fan comes on when engine overheats? Does it operate and stop intermittently?

Grey smoke is oil being burned up. It is most probably due to worn valve seals allowing oil to seep past them into the cylinders when parked overnight. During running the oil being burnt might be minimal thus you don't see any smoke.

Check the battery voltage in the morning before starting. If the voltage is low, either the battery ia failing or you have a drain on the battery. Another possible cause would be bad battery terminal connections and/or groundings.

KHLow2008
Mar 26, 2009.
Hi KHLow2008
No the fan does not come on and off intermittently. It does turn and I was able to connect it so that it will run, but then it runs constantly.
The radiator cap was rated for 13lbs. I got one that is 7 lbs and it's not overheating now but it does get warm and drops back down to normal, but that's without the thermostat.I will put the thermostat back in and see what happens. Also, while working on it tonight, we noticed that there is a hole or crack in the reserve tank. As for the fan, if it turns does that mean the motor is okay? Could it be the relay or switch?
We charged the battery, tested it and then let it sit for a while then tested it again and it had lost a little bit of it's charge. Also when reconnecting the battery cables noticed a spark on the negative terminal and heard a clicking sound inside the car, found where the noise was coming from--under the drivers side dash where the fuses are, but don't know what it is? You can feel it when it clicks. It's black, has 4 wires connected to it and says 12volt 2x15 amps.
Thanks for your help, I appreciate it. L

Tiny
Lorinsmonkey
Mar 26, 2009.
If the fan works with direct voltage applied, the motor is ok so you need to check if it is the fan relay or switch.

Check the thermosensor switch wire for proper connection. If connections are ok, disconnect and bridge them with a jumper wire. Turn ignition switch ON and if fan works, there is no problem with the relay or power supply. The fan switch would be suspect.


http://www.2carpros.com/forum/automotive_pictures/192750_ThermoSensorSwitch84Civic_1.jpg




http://www.2carpros.com/forum/automotive_pictures/192750_FanRelay84Civic_1.jpg



In the fuse box there would be some relays. No relays should be working with the ignition switch OFF, unless you have any alarm system installed. To check which relay is clicking, unplg a relay at a time and while reinstalling, if the realay clicks, note its position and let me know.

If the reserve tank is not keeping sufficient coolant level, the radiator would run dry over a period of time. During running of engine, the coolant would heat up and a certain amount would move to the reserve tank and if the level is low, air would be sucked into radiator when the coolant cools down. Repetitive action would cause the radiator level to go low resulting in overheating.

KHLow2008
Mar 27, 2009.
Okay, I have not checked any of the relays under the hood as of yet (just finished replacing tie rod ends and cv half-shaft). But under the drivers side dash is something that looks like this:


http://www.2carpros.com/forum/automotive_pictures/335677_relay_1.jpg



I'm not sure what it's supposed to run, we unplugged each wire and listened for clicking while reinstalling them. There is a black wire (negative?) and a red wire (positive?) and two blue ones, the middle terminal (87a) is capped off. The connections for the blue wires (87 and 30?) are a little loose, and the black and red wires (86 and 85?) made the clicking sound when reinstalling.

Could this be what's causing the battery to lose it's charge after several hours?

Thanks, l

Tiny
Lorinsmonkey
Mar 29, 2009.
This is an 'A' relay and is not original equipment. Check what it is for. Something is wrong with the circuit as it is working all the time.

KHLow2008
Mar 30, 2009.
The original owners were handicap-able and had the front windows converted to power windows; shortly after I got it the drivers side one went out and instead of fixing it someone just removed the electircal equipment for both windows and put regular handles back in, is it possible that's what this relay was for?
How do I go about locating where this mess of wires goes to? I wouldn't want to accidently pull on another wire that isn't associated with this relay out as there are several wires besides those four zip tied together.

Thanks, l

Tiny
Lorinsmonkey
Mar 30, 2009.
When such relays are installed, there should be a switch installed. Check if there are any switches that is in the ON position causing the relay to be activated.

Being non OEM, the wires should be running out of the harness, back track it to find out where it leads to and for what purpose.

I would not discount the possibility of the relay being for the power windows but there should still be a switch for it.

KHLow2008
Mar 30, 2009.
I didn't find an on/off switch, but I did find where it was getting power from. It was plugged into an empty fuse slot with the red wire! I pulled the wire out and disconnected the negative cable from the battery and reconnnected it and there was no clicking noise and no spark on the battery terminal.

Thanks. L

Tiny
Lorinsmonkey
Mar 30, 2009.
If you have any components not working, you would know where to look.

KHLow2008
Mar 31, 2009.
That was the problem, I removed the wires from the door and worked my way to the relay, removed the relay and the red wire that was plugged into the fuse box and my car started just fine this morning.
I also got everything else I was working on fixed and taken care of as well, thanks for all your help.
This is the best site to go to for help, I will send a donation tomorrow.

Thanks again, l

Tiny
Lorinsmonkey
Mar 31, 2009.
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