Hot Summer; Hot, Overheating V-8 Radiator Setup., Hot Summer; Hot, Overheating V-8 Radiator Setup. Options

[Chris914n6]

I have a couple of those from ebay. Ask them what part they got the measurement from because it's been inconsistent. Sometimes its the clamp area, sometimes its the lip.

[Andyrew]

Almost ready to take things apart one more time. So how crucial is it to use wye connectors versus Tee connectors? I spotted these on amazon (see picture):

https://www.amazon.com/Water-Temp-Joint-Pip...+Sensor+Adapter

And it would be much easier (and cheaper) for me to install the correct sized NPT barbed nipple to this adapter versus getting a custom wye connector.

I found it much easier for me to get stainless pipe the diameter I needed, weld up the connections I needed. I welded up quite a bit more than I thought I would and actually want to do more. It was simple with stainless wire and a mig.

[BRAVE_HELIOS]

Slowly progressing.

Quick question; which part of expansion tank must be above the block (t-stat?)... the bottom (low pressure) hose or the upper (high pressure) hose? Does it matter much Death Star or Passat expansion tank?

Almost ready to take things apart one more time. So how crucial is it to use wye connectors versus Tee connectors? I spotted these on amazon (see picture):

https://www.amazon.com/Water-Temp-Joint-Pip...+Sensor+Adapter

And it would be much easier (and cheaper) for me to install the correct sized NPT barbed nipple to this adapter versus getting a custom wye connector.

I found it much easier for me to get stainless pipe the diameter I needed, weld up the connections I needed. I welded up quite a bit more than I thought I would and actually want to do more. It was simple with stainless wire and a mig.

[Andyrew]

That upper hose. Either of those mounted in that position will work. I prefer the non rounded version, but they do fail occasionally. Thats what I run.

[veekry9]

Not less than N.
The method to calculate the size of cooling system expansion tanks,and the 'why' of the radiator having a smaller return hose.
The total volume of the system is larger than a pickup or van,so,not less than the size of tanks installed in them.

http://www.engineeringtoolbox.com/volumetr...sion-d_315.html

A small 4 cylinder's expansion tank is smaller for that reason,not equal,not the same size as a pickup's V8 tank.
Placing the tank below the head is ok,in a pinch,as the level is controlled by the pressure cap,tho level is desirable.
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[BRAVE_HELIOS]

Here is a picture of the completed setup. Still trying to get the air out of the system. Loosened the petcock on the top side of the rad and nothing... no air and no fluid. Pictures do not show the addition of a overflow tank placed in the trunk.

So; if I do not have a vacuum pump... what is the best way to purge the system of all air?

[Andyrew]

Here is a picture of the completed setup. Still trying to get the air out of the system. Loosened the petcock on the top side of the rad and nothing... no air and no fluid. Pictures do not show the addition of a overflow tank placed in the trunk.

So; if I do not have a vacuum pump... what is the best way to purge the system of all air?

Engine should be running. Hot air/water makes its way to the top thin line and feeds its way to the reservoir. Then your large line is your feed back into the cold side of the coolant line.

Basically running the engine will purge the system, aka self purging.

[Chris H.]

Yes just fill the system up and run it through a couple of heat cycles. Make sure it's all sealed up so that the system is pressurized. Put the blue cap on and make sure all the hoses are attached just like it would be if the car was 100% ready to drive. Although it may seem logical to leave a line open, it keeps the system from forcing the air out. Rev it a few times the first time to make sure your thermostat opens and feel the line going to the radiator to make sure they are hot. Watch the temp needle (at least the first time) for spikes in case you have a big air pocket. Get the engine up to temp and then shut it off. Then..(the hard part)....leave it alone and let it cool off completely. When you check the coolant the level should be down a quart or so. Maybe more. A couple more like that and you should be good. In fact once you know that you don't have any serious bubbles you can drive it around a block or two. Then very quickly you won't have to add any. BTW I never got anything out of my radiator bleeder either. Probably would now but the system is bled.

[BRAVE_HELIOS]

An update (pictures to follow);

I have the system all together and I thought it was going well. I took it for a drive at around dusk where the ambient temperature was 67 degrees and the car only got up to around 190 degrees. This is a marked improvement considering that in the past; even on a 40 degree day, the engine temp would go past 200. Well; last night, I let it idle in the garage to see what would happen and it overheated. I mean the temp got up to around 230 and the coolant was boiling over in the overflow tank. Also the fan never came on (it is supposed to come on at 180). I did check and the fan does work. I shut it down immediately and let it cool off. As it cooled, it sucked up the coolant out of the overflow tank and back into the expansion tank and engine.

Prior to this; I tried to bleed the system. I lifted the rear end which lowered the rad and I did end up getting fluid to come out of the rad bleed petcock (upper corner of rad). I also mended the holes I drilled in the rad shroud.
After the boiling coolant episode, I noticed that no coolant was coming out of the rad bleeder.

I do have a setup where lines are coming off the main rad hoses and going to a heater core for cabin heat, and the day I took it out; I had good heat in the car too.

How much air can be in this system? The temp sensor for the fan is located by the t-stat. Is the reason that the fan did not come on because of an air pocket located by the temp sensor? I guess I really need to understand how the vacuum/manometer etc… system works and how to set one up for my system.

Any other suggestions?

Yes just fill the system up and run it through a couple of heat cycles. Make sure it's all sealed up so that the system is pressurized. Put the blue cap on and make sure all the hoses are attached just like it would be if the car was 100% ready to drive. Although it may seem logical to leave a line open, it keeps the system from forcing the air out. Rev it a few times the first time to make sure your thermostat opens and feel the line going to the radiator to make sure they are hot. Watch the temp needle (at least the first time) for spikes in case you have a big air pocket. Get the engine up to temp and then shut it off. Then..(the hard part)....leave it alone and let it cool off completely. When you check the coolant the level should be down a quart or so. Maybe more. A couple more like that and you should be good. In fact once you know that you don't have any serious bubbles you can drive it around a block or two. Then very quickly you won't have to add any. BTW I never got anything out of my radiator bleeder either. Probably would now but the system is bled.

[v82go]

Do you have a manual over-ride switch for your fan ?

On my system I have a manual switch for the fans, I usually turn on the fans when the temp reaches 180 degrees

I would install a on/off switch to control your fan, refill the system, start and bleed the system again.

You must have a running fan when stationary.

[Andyrew]

Put one of these powering a 12ga wire and a relay to control your fans. Put the probe in the radiator fins.


https://www.amazon.com/gp/aw/d/B00K75QRZA/r...&ref=plSrch




You need to have the system purge a couple times in order for the expansion tank to functuon correctly.

[socal1200r]

I had similar overheating issues with a 2000 Sonoma with an LT4 and T56 swap. It sounds like you've tried numerous times to "purge" the system of any air, and it may not be that now that you've done it a few times. I would install a manual switch to turn the fans on remotely, independent of the t-stat. I would also replace the t-stat with a new one, to eliminate that as the source. Lastly, I would take it somewhere to get it professionally pressure flushed. How's the water pump? Is it up to the task of pulling in and pushing out coolant all that distance from the engine to the front of the car and back?

[Andyrew]

Quick question. How fast is it getting up to temp? Do you have a thermostat? Do you have holes in your thermostat? How new is your water pump?

[cali914]

Man with all the money and time your spending get a renegade Ron Davis radiator and call it. You are trying to reinvent the wheel. I did that ten years ago three different water pumps three different radiators hole in the hood, hole in the bottom of trunk compartment, cut open the fenders and kept having the same problem. I purchased the Ron Davis Radiator hooked up a Meizere 55gm water pump and never got above 195 on a hot day. 160 to 180 all day most days. Also if you do that you eliminate the main cooling factor from. The equation. So if your still overheating after that fix you have a better chance of isolating the problem. I'm using the same radiator with my 3.5 v6 Honda engine and its less horsepower but stays at 170- 180 all day with a 180 degree thermostat

[v82go]

One more note/

I would remove the thermostat and use my manual fan switch for warm ups.

I tried a 160 degree thermostat (with holes) on mine it would not open as it was suppose to. May have been defective, but with it removed I don't worry about it.

My engine with fans off will come to temp fairly quick except in the dead of winter .

[BRAVE_HELIOS]

I do have a manual switch. It is located on the center console, to the right of the temp gauge. It also has a 160 degree t-stat installed with many small holes drilled around the flat surface. I am trying to avoid going to an electric water pump, but it is heading that way, it seems. I think I will remove the t-stat and replace it with a re-stricter washer and see what happens.




Oh what the heck... here is a picture of the interior; complete with Fiat X-19 arm rests!




[q1uote name='v82go' date='Sep 29 2016, 09:13 AM' post='2404724']
One more note/

I would remove the thermostat and use my manual fan switch for warm ups.

I tried a 160 degree thermostat (with holes) on mine it would not open as it was suppose to. May have been defective, but with it removed I don't worry about it.

My engine with fans off will come to temp fairly quick except in the dead of winter .
[/quote]

[Mike Bellis]

When is the last time you replace your water pump? V8 conversions us a big block Mopar pump and they do go bad. Most of them are stamped steel impellers and I've seen these blades break off and or corrode.

[jimkelly]

hum (IMG:style_emoticons/default/idea.gif)

When is the last time you replace your water pump? V8 conversions us a big block Mopar pump and they do go bad. Most of them are stamped steel impellers and I've seen these blades break off and or corrode.

[BRAVE_HELIOS]

God, if I have to take apart the water pump one more time! I can tell you I bought a rebuilt unit from a chap on this forum a few years ago and I am quite certain it has steel impellers. There has to be a way to know the pump is working correctly without taking it all apart!

When is the last time you replace your water pump? V8 conversions us a big block Mopar pump and they do go bad. Most of them are stamped steel impellers and I've seen these blades break off and or corrode.

[matthepcat]

When is the last time you replace your water pump? V8 conversions us a big block Mopar pump and they do go bad. Most of them are stamped steel impellers and I've seen these blades break off and or corrode.

Are the high quality electric pumps good enough to remove those big block Mopar pumps?