UPDATED :) Temp won't come down no matter what
UPDATED :) Temp won't come down no matter what Well late update on overheating prob. It was still having same issue but not as hot. I purchased stock GM balancer and what do you know she can sit in driveway idling and not get over 185 now.
Just thought i would pass info along in case someone else runs into same issue.
I have a LS1 in 66 Nova. The temp always stayed at 170 idling. It recently had Vintage Air Conditioning and Heat swap. The temp will now keep climbing up to 230 and beyond if I let it keep running.
The bottom lower radiator hose is also staying ice cold.
I have filled system disconnecting top hose and adding coolant here like others recommended. I have removed thermostat and verified its opening correctly.
I have others that say air bubble is present still. How the hell do you get this to come out if that is the case. We now have car raised up on car ramps to try to make bubble if present at highest point. I can rev engine to 3000RPM and temp will come down but then starts to creep again after I let off accelerator.
The fans are also programmed to come on earlier and are both working correctly.
I am looking to purchase this next and see what happens.
http://www.jagsthatrun.com/Pages/Par...ightGlass.html
UPDATE 04-22-11 Thanks everyone for your tips and ideas!
I bought funnel kit seemed to help some. The temp will rise but not as fast and bottom hose seems to get a little warmer now. It did not go over 225 sitting at light idling. I still think it should run cooler. I'm just going to drive it for awhile and monitor her see if it gets better. If issue persist will look into a high flow pump and maybe see about biggest radiator I can squeeze in.
The squeaking sound is gone, I put a new belt on today when checking to see if water-pump was culprit.
Just thought i would pass info along in case someone else runs into same issue.
I have a LS1 in 66 Nova. The temp always stayed at 170 idling. It recently had Vintage Air Conditioning and Heat swap. The temp will now keep climbing up to 230 and beyond if I let it keep running.
The bottom lower radiator hose is also staying ice cold.
I have filled system disconnecting top hose and adding coolant here like others recommended. I have removed thermostat and verified its opening correctly.
I have others that say air bubble is present still. How the hell do you get this to come out if that is the case. We now have car raised up on car ramps to try to make bubble if present at highest point. I can rev engine to 3000RPM and temp will come down but then starts to creep again after I let off accelerator.
The fans are also programmed to come on earlier and are both working correctly.
I am looking to purchase this next and see what happens.
http://www.jagsthatrun.com/Pages/Par...ightGlass.html
UPDATE 04-22-11 Thanks everyone for your tips and ideas!
I bought funnel kit seemed to help some. The temp will rise but not as fast and bottom hose seems to get a little warmer now. It did not go over 225 sitting at light idling. I still think it should run cooler. I'm just going to drive it for awhile and monitor her see if it gets better. If issue persist will look into a high flow pump and maybe see about biggest radiator I can squeeze in.
The squeaking sound is gone, I put a new belt on today when checking to see if water-pump was culprit.
Last edited by shoebox66; Apr 2, 2012 at 08:11 PM.
I had 93 Formula with LT1 and bleed screws made it hell of lot easier.
I had the same issue with my silverado a couple months ago (stay cooled when driving down the road, but once I stopped, it would climb), it turned out to be my water pump even though the weep hole wasn't leaking...
But before spending money on a new pump, I would make sure there are no air bubbles...when you say disconnect the top hose, do you mean the small hose going to theTB/intake? When I flushed the system on my t/a, I just left the radiator cap off and would add from there as the car warmed up and the t-stat would open. I haven't had any issues with air in the system in the 3 times that I have done that.
But before spending money on a new pump, I would make sure there are no air bubbles...when you say disconnect the top hose, do you mean the small hose going to theTB/intake? When I flushed the system on my t/a, I just left the radiator cap off and would add from there as the car warmed up and the t-stat would open. I haven't had any issues with air in the system in the 3 times that I have done that.
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I had the same issue with my silverado a couple months ago (stay cooled when driving down the road, but once I stopped, it would climb), it turned out to be my water pump even though the weep hole wasn't leaking...
But before spending money on a new pump, I would make sure there are no air bubbles...when you say disconnect the top hose, do you mean the small hose going to theTB/intake? When I flushed the system on my t/a, I just left the radiator cap off and would add from there as the car warmed up and the t-stat would open. I haven't had any issues with air in the system in the 3 times that I have done that.
But before spending money on a new pump, I would make sure there are no air bubbles...when you say disconnect the top hose, do you mean the small hose going to theTB/intake? When I flushed the system on my t/a, I just left the radiator cap off and would add from there as the car warmed up and the t-stat would open. I haven't had any issues with air in the system in the 3 times that I have done that.
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Verdad Gallardo This also has one of those Billet overflow catch cans. I am also being told air could be trapped in there. I'm going to disconnect hose from it and use empty anti-freeze bottle as overflow while filling till air is out and then reconnect catch can.
Heating 
The coolant cross over line at the front of the engine, is it caped off?? If it is its makes it VERY hard to get all the air out of the system. This nipple needs to go to a spot on the radiator. The factory routing on F-bodys is to the throttle body and then to a spot on the radiator near the cap. Most people by-pass the TB and go right to the radiator.
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
Bleed air out from the steam tube.
The overflow bottle has to be vented.
The line to the overflow bottle has to be on the upper port of the radiator cap neck; the steam tube goes to the lower port.
The overflow bottle has to be vented.
The line to the overflow bottle has to be on the upper port of the radiator cap neck; the steam tube goes to the lower port.
Joecar The overflow can hose comes from bottom to connection coming off radiator.
The catch can has a vent on top.
If it helps this is what I'm running for a catch can.
http://www.jegs.com/i/JEGS+Performan...51137/10002/-1
The catch can has a vent on top.
If it helps this is what I'm running for a catch can.
http://www.jegs.com/i/JEGS+Performan...51137/10002/-1
The air pocket will be at the highest point in the cooling system, so that's where you need to bleed it. On my Mav, the highest point just happens to be the fill cap, so it's painfully easy for me. Just like an old-school car should be...
Start w/ a cold engine
Remove rad. cap
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until coolant reaches 210F
Shut off engine
Remove cap
Start engine
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until coolant reaches 210F
Shut off engine
Remove cap
Top off
Remove rad. cap
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until coolant reaches 210F
Shut off engine
Remove cap
Start engine
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until coolant reaches 210F
Shut off engine
Remove cap
Top off
TECH Fanatic
Joined: Jul 2010
Posts: 1,756
Likes: 4
From: Maryland
I have never been inside an LSX water pump, but I have seen first hand that all others (esp the LT-1's) spin the impeller on the shaft and cause this complaint in higher HP/RPM motors. I would try a water pump.
It just does not make sense that would be my water pump as everything was running perfect before ac & heat install which required draining anti-freeze to install heater hoses.