Overheating Prob. 86 Civic, Checked the obvious, Any ideas please

[Sarcoise]

Hey everyone, I've been through hundreds of post and seen many relating to overheating probs, but all seemed to point to "headgasket". Well, I've just replaced the headgasket - did a rather fine job if I don't say so myself - And on the 1st day out for a test drive, the car did fine for the 1st 3-4 hours, but at one point I was stuck in traffic and payed CLOSE attention to the temp guage, it was slowly rising. It got about 7/8 way to RED and I had to stop the car. Since then I have "straight wired" the fan (bypasssing the temp sensor for an always on fan), checked for air in system (used the bleed screw and let the system bleed itself out) replaced the thermostat, flushed out the radiator (not the block, I need some info on how to do this) and I still have the overheating problem. It's kinda strange, if i'm runnin on the interstate at about 80mph, the engine runs at normal temp. If I begin to get in any traffic, the temp guage rises and rises untill I deem necessary to shut down. At first the car didn't overheat at all - untill that first time when it started in bad traffic. Now it overheats if my speed drops below 50mph! Again, the fan is always on, I turn the heater on to help with cooling (which reminds me, at one point, I had the heater on to help with cooling and the heater went COLD even though the engine was HOT).
Could engine timing play this much of a role in engine temp? When I was timing the engine, my book said to "refer to the emissions sticker under the hood". My car is so old, no sticker remains in place - so I am unsure what mark I am supposed to use for timing. I simply plugged the 2 vacume lines running to the dist. and timed it where it sounded the best. (I know i know, not the right way to do it)
Any ideas would be great - Thanks in advance.

[lxndr]

If your heater went cold even though your engine was hot, that's usually a good indication that you don't have enough water in the cooling system or the water isn't circulating. There are several possible causes (not necessarily in this order):

1) Bad water pump
2) Head warped
3) Head cracked (not likely unless it has severely overheated or frozen)
4) Block cracked
5) Clog in system
6) Sludge in block
7) Bad or loose radiator/heater hoses
8) Leaking heater core
9) Radiator cap pressure too low


Is your car blowing any smoke or steam?
Is your carpet damp (indication of bad heater core)?
Does your oil look like chocolate milk?

Any leaks in the system should be obvious since they would start dribbling, bubbling or squirting when the car warms up. The only leaks that would not be obvious would be a bad water pump seal or the heater core. It's also possible that the head has warped enough to where the head gasket is not sealing properly. Did you check the head for flatness before reinstalling it?

I'm not trying to overwhelm you, it's probably something simple. These are just some examples of the things you should check. You could also try using a bottle of "radiator stop leak" to see if it will seal a pinhole in the system. Use the minimum recommended amount since the "radiator stop leak" itself can clog the system.


Anyone else have some ideas?

[Figori]

I think you need to try to flush out your system.. Not just the Radiator. But that is just my . I hope to have RexSi up and running by tonight... So I hope I don't have any overheating problems....

[Sarcoise]

lxndr - Thanks for the reply. I have already had the head checked for cracks and resurfaced - I don't think that is the issue. How probable is it that the block itself is cracked? I was told thay are hard to crack, but I have no way of checking unless I rip the whole thing out and take it to have it checked. The water pump is a concern - although it was replaced under 5,000 miles ago when the engine was rebuilt. I have looked closly for any coolant leaking around the water pump pulley, haven't seen any. Also there is so squeeling coming from the engine when its running. Is it possible for a water pump to go bad and still pump water, but not as much volume? When I first replaced that head gas. I ran the engine with the rad. cap off and made sure that water was circulating - but I have no way to check the volume.
And No - no smoke, no water in the oil, and no water in the interior of the car. Thanks for those suggestions.

[Sarcoise]

Fogori - Did flushing your system help with any of your overheathing issues? I know it can't hurt to do it - but I don't want to get my hopes up in it solving the issue. Thanks for the suggestions

[Figori]

Well, I haven't quite got her up and running yet.. I will post more late tonight when I do.

[revhalzoo]

did you have the radiator cap pressure tested? is it eating any coolant? if its eating coolant, replace the head gasket, if you dont torque the head to the right specs the gasket will fail