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View Full Version : Bad HG/ Warped Head?


Gramentz
02-06-2007, 11:23 AM
S14 KA is still overheating. There's a brand new radiator and thermostat in. There are no coolant leaks. Car warms up like normal, then anywhere from 5-15 minutes later at idle, it will start to overheat. This is not the original KA that came with the car, if that matters at all.

Cliff notes:Lower rad. hose never gets warm, no coolant leaks, normal compression, system has been bled, heater doesn't blow warm air/hot air.

Heater rarely blows warm/ hot air. Sometimes it will, sometimes it won't.

The lower radiator hose never gets warm or hot, regardless of the temp.

Water pump does not leak and does not appear to be defective/worn etc.
I am using the stock clutch fan WITH shroud.

I have bled the system, and no matter how long the bleeder screw is open, coolant does not seem to be pushed out. If the overheating problem is in fact a giant bubble in there, the lower hose should still get warm/hot, right?

Compression results: Upon first warm-up, cylinders 3 and 4 looked abnormally low. (around 150-160s compared to cylinders 1 and 2 of around 190s.) Also upon first startup, you could smell coolant burning. I didnt think much of this, some spilled while I was filling it up.

It did not overheat at first warm up. It only started to over heat when I went for a drive, even then, the car was shut off no longer than 10 seconds later. After that drive, I replaced thermostat thinking that that is why the lower hose never gets hot. Wrong, new thermo still does not solve that problem. Yes, spring is toward the back and the little hole is facing north

Another compression test: All cylinders were above 190 and did not vary more than 20psi. Cylinder number 4s spark plug looked blackish and corroded where it seals. These are brand new plugs.

The spark plugs were a PITA to remove at first when I replaced them before first start-up. They seemed seized and cylinder number 4 looked the worst and rusted/corroded threads. This is why a warped head is crossing my mind.


Does this sound like a warped head/bad HG?

HalveBlue
02-06-2007, 01:06 PM
My guess is with coolant leak/Bad headgasket.

Does coolant magically dissapear from the overflow resevoir?

ls180sx
02-06-2007, 01:36 PM
change your oil and see if theres any coolant in it

Gramentz
02-06-2007, 01:49 PM
The reservoir level is always at the minimum level no matter how much coolant I will add. I'll drain the oil and make sure that is OK.

sw20>>s14
02-06-2007, 04:30 PM
like someone stated, check oil for hints of coolant...other than that, your lower rad hose never heating up is because your t-stat isnt opening...that would also explain why it takes 10-15 minutes for it to overheat...once its up to temp the t-stat pops open, but apparently its not...did you install it right? jiggle valve up? if you went too crazy on the RTV, sometimes it makes the valve stick closed...maybe theres a lot of air trapped in the heater core? i would check for signs of blown HG before diagnosing further...

byhi
02-06-2007, 04:33 PM
i hate to say it, but the only way to tell if you have a warped head (which is normally caused by a blown headgasket) is by taking it off and using a feelers gauge to find out, im sorry, but its true


als0 - sw20<<<s14, pm me about shippign on that headlight

aznpoopy
02-06-2007, 04:36 PM
leakdown test
tdc for testing cylinder
open rad cap
compressed air into cylinder
look for bubbles or rising/falling of coolant level
g'luck!

Gramentz
02-07-2007, 07:00 AM
Thanks for the input everyone. I'm going to check the oil first. I put the little hole on the thermostat facing up, but perhaps it shifted while I was bolting the housing on, so I'll double check that. I'll try and re-bleed it again and again too.

For the leakdown test, does it matter if the engine is warm? I have an air compressor with the basic attachments, that should work for shooting air into the cylinders right?