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I have seen posts on this forum that the LT-1 has a special t-stat unique to it . If you get a generic one that still fits it may not operate correctly for your LT-1. Just a thought, maybe get 1 from dealer if possible. Hope this helps. Kevin
...That blocks a coolant port when the stat is in one position, and opens it in another. So you have the upper valve (same as a normal stat) and then that lower disk. The purpose is to circulate coolant through the engine until it's warm...then block that loop off and simultaneously open the radiator loop for cooling to occur. If you have no stat in there, or the wrong one, coolant flow isn't controlled/managed to go where it needs to go.
You state that only one fan comes on then the other. On a 96 both fans are suppose to turn on at low speed then both go on high speed. If only one fan is on at a time there is something wrong. Also on my car when just running the elect pump I can see flow in my upper tank. I have 4 small holes drilled in my t-stat to help bleeding. I run my pump with out the motor running and have no issues getting the air out.
Need to make sure BOTH fans are working high and low, and verify the pump is wired correctly positive and ground. DC motors can run backwards if polarity is wrong.
Also the factory used to put in pellets to help seal up the coolant system. They seem to like to collect in the heater core. Hook up a hose and flush the core. I flushed a bunch of crap out of mine.
...That blocks a coolant port when the stat is in one position, and opens it in another. So you have the upper valve (same as a normal stat) and then that lower disk. The purpose is to circulate coolant through the engine until it's warm...then block that loop off and simultaneously open the radiator loop for cooling to occur. If you have no stat in there, or the wrong one, coolant flow isn't controlled/managed to go where it needs to go.
Comparing my t-stat, it looks like I've got the right one...
i have a 96 lt4 car that had the factory radiator and fan assy. while being tuned, it was running hot and the tuner noted that and advised me to cool the engine and get the ic/coil off the passenger head.
what i did was to install a dewitts radiator and spal fans assy and re-route the ic/coil to the cross bar in front of the engine and directly behind the fans. car still ran 210* no matter what, except when i let go with a blast to triple digits and the temp went down to 201*, with a 180* thermostat and the outside temps were in the 50* range. too hot for my concerns. so someone on the forum was inquiring about a koolflow water pump and i googled it and purchased one from summit racing along with a hypertech thermostat which i drilled a few holes in and installed with the koolflow pump. now the car ran in the 130* range this past weekend in 50* range outside temp. that's an 80 degree change. so now i am going to install a 160* thermostat but omit the holes and see what that does. probably when the outside temps get to the 90 - 100* days i will put the 160* drilled thermostat back in.
i have a 96 lt4 car that had the factory radiator and fan assy. while being tuned, it was running hot and the tuner noted that and advised me to cool the engine and get the ic/coil off the passenger head.
what i did was to install a dewitts radiator and spal fans assy and re-route the ic/coil to the cross bar in front of the engine and directly behind the fans. car still ran 210* no matter what, except when i let go with a blast to triple digits and the temp went down to 201*, with a 180* thermostat and the outside temps were in the 50* range. too hot for my concerns. so someone on the forum was inquiring about a koolflow water pump and i googled it and purchased one from summit racing along with a hypertech thermostat which i drilled a few holes in and installed with the koolflow pump. now the car ran in the 130* range this past weekend in 50* range outside temp. that's an 80 degree change. so now i am going to install a 160* thermostat but omit the holes and see what that does. probably when the outside temps get to the 90 - 100* days i will put the 160* drilled thermostat back in.
now back o our normal programming.
Definitely something to look into but for right now, I gotta figure out why coolant is not flowing at all...
I believe you said that you were running the electric water pump through a relay. You might want to try changing the relay - it could be causing lowered voltage to the pump after many cycles. You may also want to check voltage right at the pump.
I would actually look at current flow to the water pump. You'll have to undo a connector or two - but if that pump isn't pulling at least 5 Amps under load - something isn't right. I believe the Mezire pumps are supposed to flow about 35 Gallons/min - so if you pull the heater hose - and run the pump (even with the engine off) - you should see something on the order of half a gallon a second...
I believe you said that you were running the electric water pump through a relay. You might want to try changing the relay - it could be causing lowered voltage to the pump after many cycles. You may also want to check voltage right at the pump.
I would actually look at current flow to the water pump. You'll have to undo a connector or two - but if that pump isn't pulling at least 5 Amps under load - something isn't right. I believe the Mezire pumps are supposed to flow about 35 Gallons/min - so if you pull the heater hose - and run the pump (even with the engine off) - you should see something on the order of half a gallon a second...
Alright, so I really hope I'm not overlooking something here but I am completely baffled after tonight. So just to back track, remember I purchased another Meziere water pump b/c thats the only other thing that I thought it could originally be. Either something is blocked or pump is not turning. So that being said, I've got a brand new one on the car. I took the old one out and started doing some tests. So I went back to the basics again. Re-checked all fuses inside the car and beside the battery. All good. So I started checking wires. Now, I do have a On/Off switch for my battery b/c I rarely drive it. That being said, I unplugged the pump from the power source.
Took a volt meter and checked the current:
Looks good, right? And of course, that plug comes out of a relay that I installed up front and plugs into the matching plug for the pump.
Here is that relay:
And another pic of same relay from different angle:
So, with all of that, if shes showing 12v as shown above, when I plug the two together, the water pump should start spinning, right?
Plug these two together:
Well, when I plug them together, nothing! Bad pump maybe, right? With that being said, I take a battery charger, turn it on 12v and run the positive to the blue wire for the pump and the negative to the black wire and she starts spinning. So what is the difference in the 12v on the battery charger and the 12v running through the wire harness? Maybe its a bad connection? Tried that too. Tried jumping it wire to wire and still nothing. So, Im completely baffled right now??? 12v is 12v! So the main power source I have for the pump is ran directly from the battery(have it on an eyelet on the side post of battery) up through a relay and then from that relay it runs to the in-line relay/fuse as pictured above. And yes, I checked that relay as well and shes got 12v.
Here is 2 pics of that relay(orange wire which is soldered/connected to red wire):
So to recap...Ive got 12v going to the plug for the water pump, I plug it in, it does nothing. If I disconnect pump, plug into a battery charger and run 12v thru the positive and negative lead, it spins with no problems...Am I missing something here...???
Last edited by austinseanchris; 02-21-2019 at 11:05 PM.
That's a perfect description of a bad connection. In pic #5, do I see an overheated/melted wire? I can't follow your electrical connection description of the two relays. Can you draw an electrical diagram of your circuit? The main electrical path from the battery thru the relay(s) to the pump, and the path from the pump to ground must be with #14 gauge wire. Do you have that? Are all of your connections with GOOD solder joints? Can you show us what you call a good solder joint?
Alright, so I really hope I'm not overlooking something here but I am completely baffled after tonight. So just to back track, remember I purchased another Meziere water pump b/c thats the only other thing that I thought it could originally be. Either something is blocked or pump is not turning. So that being said, I've got a brand new one on the car. I took the old one out and started doing some tests. So I went back to the basics again. Re-checked all fuses inside the car and beside the battery. All good. So I started checking wires. Now, I do have a On/Off switch for my battery b/c I rarely drive it. That being said, I unplugged the pump from the power source.
Took a volt meter and checked the current:
Looks good, right? And of course, that plug comes out of a relay that I installed up front and plugs into the matching plug for the pump.
Here is that relay:
And another pic of same relay from different angle:
So, with all of that, if shes showing 12v as shown above, when I plug the two together, the water pump should start spinning, right?
Plug these two together:
Well, when I plug them together, nothing! Bad pump maybe, right? With that being said, I take a battery charger, turn it on 12v and run the positive to the blue wire for the pump and the negative to the black wire and she starts spinning. So what is the difference in the 12v on the battery charger and the 12v running through the wire harness? Maybe its a bad connection? Tried that too. Tried jumping it wire to wire and still nothing. So, Im completely baffled right now??? 12v is 12v! So the main power source I have for the pump is ran directly from the battery(have it on an eyelet on the side post of battery) up through a relay and then from that relay it runs to the in-line relay/fuse as pictured above. And yes, I checked that relay as well and shes got 12v.
Here is 2 pics of that relay(orange wire which is soldered/connected to red wire):
So to recap...Ive got 12v going to the plug for the water pump, I plug it in, it does nothing. If I disconnect pump, plug into a battery charger and run 12v thru the positive and negative lead, it spins with no problems...Am I missing something here...???
So did you test for voltage between the plug and the pump? If none, get rid of the stupid plug! Hard wire it!
My first thought would be a bad thermostat. I've never seen a water pump go out that wasn't leaking well in advance (as in, you know it will go out soon).
Could be a coolant temp sensor too, they are easy to test and replace.
Originally Posted by austinseanchris
These readings were from the analog gauges but the needle was pegged on hot.
What did the digital gauge say? General advice is to ignore the analog engine temp gauge. It is not a linear scale. But still, if it was pegged I also would be concerned.
My first thought would be a bad thermostat. I've never seen a water pump go out that wasn't leaking well in advance (as in, you know it will go out soon).
Could be a coolant temp sensor too, they are easy to test and replace.
What did the digital gauge say? General advice is to ignore the analog engine temp gauge. It is not a linear scale. But still, if it was pegged I also would be concerned.
3 bad thermostats in a row? All of which opened as they should when tested in hot water on the stove once the temperature was achieved...Digital temp was 263...I dont go by the analog readings.
Last edited by austinseanchris; 02-22-2019 at 05:21 PM.
I believe you said that you were running the electric water pump through a relay. You might want to try changing the relay - it could be causing lowered voltage to the pump after many cycles. You may also want to check voltage right at the pump.
I would actually look at current flow to the water pump. You'll have to undo a connector or two - but if that pump isn't pulling at least 5 Amps under load - something isn't right. I believe the Mezire pumps are supposed to flow about 35 Gallons/min - so if you pull the heater hose - and run the pump (even with the engine off) - you should see something on the order of half a gallon a second...
Do you happen to have one of these installed on your 92?
My first thought would be a bad thermostat. I've never seen a water pump go out that wasn't leaking well in advance.
Thermostat has been replaced twice. Very early post:
I do have the Meziere electric water pump and its been on for 4-ish years with no issues. New T-stat was installed at that time and was a 180 I believe.
3 bad thermostats in a row? All of which opened as they should when tested in hot water on the stove once the temperature was achieved...Digital temp was 263...I dont go by the analog readings.
No, that's not right. I didn't see the part about this being your 3rd Tstat. Sorry.
Im not sure if the electric pump is suppose to run 24/7...? Maybe someone with the same Meziere pump can chime in?
What does the plug have to do with when it runs? Of course it runs all the time.
If you have 12v before the plug and nothing after, the plug is bad. Eliminate it
Last edited by Cruisinfanatic; 02-22-2019 at 10:54 PM.
02-17-2019, 02:36 AM
LT1 doesn't use a typical stat. It's a dual valve t-stat.
