1992 Nissan 240SX: Air bubble?

[znelson]

I think there is an air bubble in my system I just cant get out. I flushed the system twice now and still have the same problem. All started about a week ago, heater blew nice and hot air. That same day as I was driving to work I noticed a ton of steam coming from the resivior on the passenger side of the car. So I pull over and the engine is overheating bad. I let it cool down and limp back to the garage. Upon inspection Im lucky, there was very little coolant left in the system. Anyways, I ran to autozone and replaced the thermostat. The car started leaking coolant from the resivoir side of the firewall, so I figured the heater core was busted and re-routed the heater feedhose back into the block. Problem solved, no leaking anymore. Car was driven all week until tonite with no issues. So I go to put the intake on tonite, and while Im there I decide to try the heater once more. (I fixed the leak by the firewall, guy that did the engine swap didnt tighten the bracket down around the hose that feeds the heater at the firewall) Burped the system with the car jacked up through the radiator cap (btw the burp screw is broke off I, found that out tonite). Coolant flows fine, but I cant get the car to warm up, even if I drive it hard it takes me a good 20mins to get the temp gauge to even approach 1/2way. It actually started blowing colder air when I started to dog the car to see if it would warm. Im completely out of ideas now, any help here? Im about to give up and take the car to get looked at (I have to get someone to tap that burp screw for me anyways)

[tonynalli]

your thermstat is stuck open...dont keep it this way its not good for the engine

[navysnail]

first, do a search for the bleeder screw, you have to remove that when you fill the system. Do a compression check on your engine too just to make sure you don't have a blown headgasket.

[znelson]

first, do a search for the bleeder screw, you have to remove that when you fill the system. Do a compression check on your engine too just to make sure you don't have a blown headgasket.

(btw the burp screw is broke off I, found that out tonite). However, I will do a compression check, thanks for the idea. On a side note the symptoms sound dead up like a open thermostat but the damn thing is brand new, maybe the autozone guy gave me the wrong one?

[tonynalli]

probably not the case that they gave you the wrong one..if it fits...it fits..take it out and check it...mabey if your bleeded screw is broken it might be allowing air in..also check the radiator cap....check the rubber suround around it to see if its broken

[navysnail]

if you take the t-stat out, put it in some almost boiling water, it should open up.

if the bleed screw is broken off, get an easy-out extractor set and a nice small drill bit and pull that sucker out. then, replace with a new one. the manifold is aluminum so do not over-tighten it or you will strip it.

[znelson]

I checked the rubber cap seal already, its good. I need to test the thermostat, Ill save it for the weekend Im tired of messing with the coolant system. As for the bleed screw, its broke off flush threaded, no way it can leak air in there.

[navysnail]

its not air getting in, the bleed screw lets traped air out.

[rogoman]

On a side note the symptoms sound dead up like a open thermostat but the damn thing is brand new, maybe the autozone guy gave me the wrong one?

It's advisable NOT to use an aftermarket thermostat; aftermarket units can cause problems like you're having and can even cause overheating. Go with an OEM unit.

Always make sure the 'steam' hole in the thermostat is facing up when installing.

[fatboy]

new parts dont nessesarily mean good parts....esp. autozone's