I'm running 3-core champion radiator, stock fan and shroud. Car runs cool as a cucumber.
couple of questions: do you have the heater hose routed correctly? Is the steam line from the back of the heads installed and routed appropriately?
If I were you I would eliminate the stock water pump and use hose adapters.
I didn't route the lines myself. I can only assume that the last owner did route them correctly. I should raise the rear end again and burp the system to make sure I don't have air in the system.
With regards to the adaptors, I was going to go this route but the routing has me very confused. thus I when with the stock water pump.
Are you aware of any V8's running the stock radiator? Do you have to remove the front hood to install a new radiator?
There are people on this forum who are runnign the stock rad with V8, but I don't remember who.
You don't have to remove the hood to replace radiator.
I wouldn't assume the previous owner knew what he or she was doing regarding the cooling system. Verify everything.
I think I may have air in the system..... I ran another test just now
Outside Temp is in the low 60's ...
Ran the car for about 10 minutes Before \ NOW 157 \ 149 Degrees >> Top Inlet of the stock Fiero radiator. 120 \ 146 Degrees >> At the radiator cap 152 \ 100 Degrees >> At the rear pipe before entering the stock water pump housing 187 \ 222 Degrees >> Rear corvette reserve tank 217 \ 202 Degrees >> At the rear facing cylinder Head Max out >> stock Fiero temp gauge
Note I had the pump in test mode 100% cycle \ Fan On
once I turn the car off... the over flow tank gets full and dumps out the cap .
Coolant dumping from the tank after engine off is probably due to heat soak, unless you have the vented radiator cap (assuming you're referring to the stock overflow) that allows coolant to flow out of the radiator. If it's not a vented radiator cap, then it probably still has flow problems and the engine is getting pretty hot.
Did you check you temperature sensor and wiring to make sure they are good?
[This message has been edited by cyrus88 (edited 04-28-2022).]
Coolant dumping from the tank after engine off is probably due to heat soak, unless you have the vented radiator cap (assuming you're referring to the stock overflow) that allows coolant to flow out of the radiator. If it's not a vented radiator cap, then it probably still has flow problems and the engine is getting pretty hot.
Did you check you temperature sensor and wiring to make sure they are good?
It's the stock over flow tank that has a vented cap. The overflow tank over fills and dumps out the vented cap.
I am planning on getting a new water temperature sensor this weekend. Time permitting.
There should only be one wire to the sensor. Do a visual for fraying, cracking, poor connection etc.
Just to be clear, by stock overflow tank, I mean the stock Fiero tank, not a Camaro or Vette tank. >>>>> Correct. the fiero front stock tank. It fills up and pours out the vented cap. I also have the stock vette tank in the rear.
Here is what my cap looks like:
Replace?
I did find one wire that was melted but it appears to be an oil pressure or temperature. I fixed it and re-routed it . It's located on the lower side of the block facing the rear bumper. I ordered new O2 sensors pending installation. Only the outter connecter is melted a little the wires at the are OK. Circled connector
What do you think these sensor are?
[This message has been edited by str8maxn (edited 05-01-2022).]
Okay, I am talking about the RADIATOR cap being vented or non-vented, not the overflow cap.
The temp sensor in the water pump is for the PCM. The gauge gets the temp from the sensor in the head. Normally, on the LT-1, the sensor is in the left cylinder head (so it's close to the water pump), but I don't know what the previous owner did with your engine.
I can't tell from your last picture what those sensors are, or what they're supposed to measure.
Ahhhh ... the radiator has an after market radiator cap . . . ThermoCap
Take the cap off and pull on the center poppet. If it's spring-loaded and pulls back, it's non-vented, otherwise it's vented. Fieros require non-vented.
The Camaros and Firebirds with LT-1 didn't have caps on the radiator, they just had them on the overflow/expansion tank, and they were 18-PSI. I use a small expansion tank in the engine bay (makes it easier to fill and remove air out of the system) with 22-PSI cap, and an 18-PSI cap on the radiator so that I can use the stock Fiero overflow tank.
[This message has been edited by cyrus88 (edited 05-02-2022).]
Looks like he put a T into the CTS port on the cylinder head, then screwed the ECM CTS into one branch and the Fiero gauge sender (or switch?) into the other branch. That will hurt response and accuracy on both because they're not getting coolant flowing over the sensor.
I just realized the far one has two wires. That means it's either the fan switch or the temp light switch.
The three terminal sensor I linked should go into the waterpump. Two wires go to the ECM, the third goes to the gauge input. FieroGuru posted the pinout, or you can find it online.
You should not need a fan switch, as the ECM should be operating the fan (verify that wire is hooked up to C500-D1)
Your temperature light switch (don't remember if single or two wire) should go into the cylinder head where the brass T in your photo is currently installed.
I just realized the far one has two wires. That means it's either the fan switch or the temp light switch.
The three terminal sensor I linked should go into the waterpump. Two wires go to the ECM, the third goes to the gauge input. FieroGuru posted the pinout, or you can find it online.
You should not need a fan switch, as the ECM should be operating the fan (verify that wire is hooked up to C500-D1)
Your temperature light switch (don't remember if single or two wire) should go into the cylinder head where the brass T in your photo is currently installed.
I was able to trace one of the two connectors today.
Its the connector that I fixed because it got to close to the exhaust and melted. One end is grounded to the engine block the other wire appears to travel into the cab.
The foreground sensor is the normal 2 wire CTS, so it should have two wires.
The Fiero manual says the stock gauge sender and are in the same unit. Both circuits go to the C500 connector and ground through the housing.
If that device is wired correctly, then it's a different kind of switch, which needs an external ground.
I am hoping to install the new champion radiator this weekend. If I still get higher temp reading ... I'll have to dig deeper into these plugs\sensors.
I got the new champion radiator; while filling the system noticed I don't have any heat coming from the heater. Not sure why.
I ran the car for 30+ minutes on the jack stands and temp gauge still maxed out.
Damn... this is getting annoying
Fieros are finnicky to fill. What I've found works best when starting with a dry system:
=>Remove front radiator cap =>Disconnect upper heater core hose =>Remove thermostat if required by engine design =>Fill from engine until coolant rises to level of front radiator cap =>Install front radiator cap =>Continue to fill until coolant rises to level of upper heater core hose =>Reconnect upper heater core hose =>Continue to fill until full at engine =>Install engine coolant fill cap =>Fill front overflow bottle =>Run for 1-2 complete thermal cycles and check level in front overflow bottle
Following Will's advise.. I seem to have filled and burped the cooling system correctly. I now have heat coming from the heater and the car is running within the range I set the TinyCWA control to. I am still getting incorrect readings from the stock gauge but I'm not over heating like before.
I'll have to trouble shoot this issue a little bit more.
I am still having over heating problems. The car runs great for the first 30-60 minutes depending on weather. Once I hit 205 degrees; I lose power and it runs like crap. During the last outing, I noticed steam coming from the rear vent hose.
I've done the follwoing:
Gutted the stock water pump (LT1) and pulled the thermo stat Added a BMW electric water pump at the lower radiator outlet Added a water pump controller set to 165 degrees Added a new 3 row aluminum champion radiator Added a high flow Volvo electric fan
I purchased a new stock water pump and 160 degree thermo stat. Can I run both at the same time?
My assumption is that since its reverse flow the gulled water pump is not routing correctly.
So, looking at your diagram, the coolant routing from the output of the electrical water pump should go to the top fittings on the engine-block-adapters. The bottom fittings go to the thermostat housing.
Here's a quick edit of your sketch: (This is with the CSR water pump)
Look at this diagram I posted a while back. Also don't forget to route heater hoses, or a bypass if you're not using the heater, so a small amount of coolant can circulate through the engine before the thermostat opens.
I'm not aware of any Kits being available. You'll have to make your own adapters (see page 1 of this thread where I posted about it), or contact V8Archie and see if he has any available.
You could make some adapters if you can use CAD and get the adapter plates laser cut from some 1/2" AL or SS from somewhere like OSHcut. You would need to get the correct tap to adapt to the AN fittings, you could reuse the fittings from the kit you bought. I would undersize all the holes and drill them out to their final sizes. You can cut some gaskets from a sheet of gasket material.
Just an idea to make use of the kit you bought without too much time, effort, or money to invest into getting the correct adapter plates. If you need thicker than 1/2" material you will need to have parts machined instead.
I did some searching and found nothing off the shelf for your application.
