View previous topic :: View next topic |
Author |
Message |
iansane Member
Joined: 16 Jan 2004 Posts: 5740 Location: Bothell
1991 Pontiac Trans Am
|
Posted: Sat Aug 16, 2014 11:42 am Post subject: Modified cooling system woes |
|
|
So I keep overheating the firebird. I've come to the conclusion that coolant is not circulating correctly. My temp gauge almost peaks at 240 after a little bit of a drive or idling in the driveway for 15 minutes or so, however the radiator is cold to the touch. I've unhooked the fans because they would be kicking on even with the radiator ice cold.
I've replaced the thermostat twice and even cracked open the backside of the h2o pump to see if the impeller became disconnected. It did not so now I have a new waterpump. The radiator is canted forward, but it's the stock radiator. So the angle of the inlet and outlet are now opposite what would make a smooth transition. I almost feel like I've got air trapped on the outside of the thermostat and that's preventing it from opening? The water outlet housing points straight down so it seems a likely spot for an air pocket.
I'm at a loss now. _________________
Quote: | Sometimes I actually think I'm slightly retarded in the mouth. |
|
|
Back to top |
|
|
chevymad Master B
Joined: 11 Jan 2004 Posts: 5474
1987 Pontiac Formula
|
Posted: Sat Aug 16, 2014 12:14 pm Post subject: |
|
|
Tried vacuum bleeding? or find an entry to the cooling system near the top of the motor to fill it.
Ls motors have the thermo in the bottom hose if I remember right. Systems like that can be hard to bleed at times. Does the thermo have a bleed hole? If not maybe drill a 1/16th hole in it.
Some car companies actually had instructions to jack the front of the car up 3ft in the air so that the radiator cap would be the highest point of the system then fill with coolant. |
|
Back to top |
|
|
iansane Member
Joined: 16 Jan 2004 Posts: 5740 Location: Bothell
1991 Pontiac Trans Am
|
Posted: Sat Aug 16, 2014 4:25 pm Post subject: |
|
|
I don't have any apparatus to vacuum bleed but I'd sure like to...
It is a definite pain, especially since the actual radiator cap is at the back of the engine compartment. With the radiator pushed so far forward I had to provide a 'high' point and bought one of those pressurized coolant recovery tanks to plumb into the system off the radiator.
The thermo has one of those jingly bleeder things that I cut off so it's just a hole.
My bmw is like that. Easiest to bleed when the front is ridiculously high in the air. _________________
Quote: | Sometimes I actually think I'm slightly retarded in the mouth. |
|
|
Back to top |
|
|
iansane Member
Joined: 16 Jan 2004 Posts: 5740 Location: Bothell
1991 Pontiac Trans Am
|
Posted: Sat Aug 16, 2014 8:17 pm Post subject: |
|
|
Well, today I tried to bleed it again. I picked up one of those cooling system funnels.
I put that one the radiator and jacked the front passenger side up as high as I could get it while having the car in the driveway. I think I had 2-3' of air under the tire. Started the car and kept my hand on the rad. After a few minutes the fan was trying to kick on so I started squeezing the lower hose to see if I could suction some coolant up to the pump. After a few hard squeezes I heard some funky gurgling/poping noises. I kept squeezing and then just heard a whoosh while the funnel emptied at least a half gallon into the rad. That was a hell of a relief. The radiator started to warm up and I think that might have solved it.
I let the car cool and came back a few hours later and within a couple minutes of firing off the car on level ground the radiator started warming up and the temp gauge took at least twice as long to come up.
Now to fix the missfire issues. I'm absolutely destroying my taylor wires because they're laying up against the headers. Even with the mesh high temp boot covers I've destroyed two sets in three months. I'm going to order the set with 90* boots and hopefully that pulls the wires far enough away. They're only double the price of the factory LS1 wires, why not? _________________
Quote: | Sometimes I actually think I'm slightly retarded in the mouth. |
|
|
Back to top |
|
|
aaron_sK Member
Joined: 23 Jan 2006 Posts: 8834 Location: Back in beautiful Tacompton
1987 Chevrolet Camaro IROC-Z
|
Posted: Sun Aug 17, 2014 8:42 am Post subject: |
|
|
Haha... BMW was the company Brandon mentioned that required you to get the front of the car up high before filling the system.
Do you run a heater core?
How is the surge tank plumbed in?
I'm sure burping it like that is a solid fix, but the surge tank should have prevented this issue, which has me a bit confused. |
|
Back to top |
|
|
iansane Member
Joined: 16 Jan 2004 Posts: 5740 Location: Bothell
1991 Pontiac Trans Am
|
Posted: Sun Aug 17, 2014 2:13 pm Post subject: |
|
|
Heater core, yes. Originally I had the tank plumbed into the feed side of the heater core. This time around I ran it to the smaller hose connection on the radiator on the passenger side. |
|
Back to top |
|
|
Twilightoptics Hardcore (12sec Club)
Joined: 13 Jan 2004 Posts: 9191 Location: Auburn , WA
1987 Chevrolet Camaro IROC-Z
|
Posted: Sun Aug 17, 2014 2:52 pm Post subject: |
|
|
The problem is even though it has a jiggle valve, the t-stat on the bottom just holds air and doesn't get hot enough to move the thermostat under pressure on initial fill.
All the LS based units I work with, van cutaways, have a sticker stating to run the engine with the cap off until the air burps out like that. We've got one of those funnels just for that. _________________ A redline a day keeps the carbon away! |
|
Back to top |
|
|
|