uh oh
Race Director
Joined: Oct 2008
Posts: 17,982
Likes: 1,072
From: Lansing MI
Define refurb … Did you have the intake off ? You did didn't you.
Which way did you install the intake gaskets ?
Seem like there is a thread here where someone else had this exact problem and installed the intake gaskets with backwards.
Which way did you install the intake gaskets ?
Seem like there is a thread here where someone else had this exact problem and installed the intake gaskets with backwards.
Burning Brakes
Joined: Sep 2010
Posts: 925
Likes: 379
I experienced the same symptoms and the cause was a radiator cap that could no longer keep the cooling system pressurized. The coolant would boil after shutting the engine off just as yours does in the video. You can have the cap pressure checked to troubleshoot the issue.
Thread Starter
Oil Producer
Joined: Apr 2014
Posts: 9,363
Likes: 2,734
I experienced the same symptoms and the cause was a radiator cap that could no longer keep the cooling system pressurized. The coolant would boil after shutting the engine off just as yours does in the video. You can have the cap pressure checked to troubleshoot the issue.
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Safety Car
Joined: Aug 2013
Posts: 4,424
Likes: 603
From: Minneapolis Mn
Had 2 cars that had airlocks in the heater core that found a trick that worked in both cases. Car at operating temp, heater turned on full. Had a parking ramp with a high incline in it, drove the cars up several floors in low gear with a higher rpm. In both cases I was able to get the air bubbles to blow through to the radiator. Hope that helps with your heater issue.
Good luck.
Good luck.
Thread Starter
Oil Producer
Joined: Apr 2014
Posts: 9,363
Likes: 2,734
dogs i was looking at this and it appears the valves default position is actually open. it closes when u ask for ac or something like that. its possible its stuck closed for sure. i will try to raise the front end first.
one thing to note is that i recently added the factory kc4 cooler on this base car. it takes pressurezed coolant from the block and sends it back to the water pump via the return line from the heatercore.
so i see a situation where cars with this cooler circut have a harder time burping air from heatercores because the return line may end up being pressurized by the fluid in the kc4 circut.
Thread Starter
Oil Producer
Joined: Apr 2014
Posts: 9,363
Likes: 2,734
circling back on my uh oh thread.
put the nose waaaaaay up in the air tonight as i installed the air dam.
once finished the airdam, i wrapped a set of vice grips teeth in leather glove and pinched off the kc4 return line which comes in downstream of the heatercore on the heatercores return line.
ran the car with cap off for 5 min with heat on and i had heat. revved engine to 2500 poured in fluid to rad and sealed a new cap.
so id say im bled. i have heat now. no idea if clamping kc4 return line did anything but i didnt want the air pocket fighting block pressure which is what it does.
if i get no heat out for a drive, i think i need to install an orifice in the kc4 return line. i never thought to research if there was a restrictor in the factory solid lines.
i also removed the restrictors at the back of the intake manifold but later cars have that removed so id doubt if the steam crossover had anything to do with it.
will circle back one more time if all is well.
now to go for another rip!!!!
put the nose waaaaaay up in the air tonight as i installed the air dam.
once finished the airdam, i wrapped a set of vice grips teeth in leather glove and pinched off the kc4 return line which comes in downstream of the heatercore on the heatercores return line.
ran the car with cap off for 5 min with heat on and i had heat. revved engine to 2500 poured in fluid to rad and sealed a new cap.
so id say im bled. i have heat now. no idea if clamping kc4 return line did anything but i didnt want the air pocket fighting block pressure which is what it does.
if i get no heat out for a drive, i think i need to install an orifice in the kc4 return line. i never thought to research if there was a restrictor in the factory solid lines.
i also removed the restrictors at the back of the intake manifold but later cars have that removed so id doubt if the steam crossover had anything to do with it.
will circle back one more time if all is well.
now to go for another rip!!!!