Early C4 Thermostat
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
Early C4 Thermostat
I'm replacing my faulty thermostat on my '85 but i'm having some trouble with the stud/bolt with the ground wire on it. Should be simple enough but I cant get the top nut to seperate from the ground. Any ideas?
Race Director
Joined: Jun 2004
Posts: 13,961
Likes: 707
From: WI
Is it super rusty? You may want to replace both, then put a new end on the wire. You can make you own with a nut and new end, very inexpensive. You may want to unplug the computer and battery if you mess with it a lot. Pack the new or cleaned setup with grease so it doesn't get rusty.
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
Its not rusty at all, just cant get it seperated. I dont understand why there are so many things in the way. Like the coolant hose that goes on the bottom of the throttle body, I think its all just bad design. I would snip the wire but I have no way to get to the store to get another end right now. I just thought this was going to be super easy.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
I this one of the two bolts that hols the t-stat housing to the intake manifold? I only remember the EGR solenoid being held by one of the bolts.
Last edited by RRT vette; Dec 8, 2006 at 02:27 PM.
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
Yes on the early C4's theres a bolt on one side and a stud on the other with a ground wire and a nut on it. These bolt the thermostat housing to the manifold. I managed to get the stud out by cutting the ground wire so looks like i'll have to fix the wire back to the stud somehow. I didnt know it was for the EGR. Thanks for the help though
Thread Starter
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
I managed to get everything put back together, but now its leaking coolant really bad when I start it up. I used the gasket and tightened the bolts down as tight as they will go and its still leaking. Will someone please help me, this is turning into a nightmare.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Double check to see if the leak is from the between the housing and intake (gasket) or is it leaking around the hose? Did you check to see of the housing is FLAT? Some are known to warp. Place it flat on a piece of glass to check.
If it is the gasket. Replace the gasket and use "THE RIGHT STUFF" on the intake then place gasket into position and use "THE RIGHT STUFF" on the thermostat housing. Place bolts into housing and position on the intake and tighten to 18-23 foot pounds.
**A thin amount of sealer should be used, just wipe on both surfaces with your finger.
If it is the hose, check you clamp for damage and retighten the clamp or replace.
You might do a search on drilling a hole in our thermostat prior to installation. [This will allow air to escape easier as you refill the system]. The hole should be a single hole about 3/32 diameter. Position the thermostat with the hole so the hole is toward the front of the engine.
If it is the gasket. Replace the gasket and use "THE RIGHT STUFF" on the intake then place gasket into position and use "THE RIGHT STUFF" on the thermostat housing. Place bolts into housing and position on the intake and tighten to 18-23 foot pounds.
**A thin amount of sealer should be used, just wipe on both surfaces with your finger.
If it is the hose, check you clamp for damage and retighten the clamp or replace.
You might do a search on drilling a hole in our thermostat prior to installation. [This will allow air to escape easier as you refill the system]. The hole should be a single hole about 3/32 diameter. Position the thermostat with the hole so the hole is toward the front of the engine.
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