V1 Purging Air from Coolant System

[David]

Was thinking of use that loop for something else but I have the thermostat housing that has the ports for the oil cooler already. So what I get put of this conversation. Is that doing this mod is the same as leaving the loop.

Also snice we are on the topic of coolant and thermostat housing. Like I said i have the housing that has ports for the oil cooler. Does anyone know where you can get one?

I searched everywhere and no one lists one. GM has it has discontinued. View attachment 54895

So I dove deep and nowhere they have this LSJ thermostat housing with the oil cooler nipples.

So I realized that the Saab 9-3 used a B207 which is almost identical to the LSJ. So I hit up Rock Auto and behold they have the thermostat housing which looks identical. They also have the same water outlet seal. So im pretty sure its the same.

 

[Robinjo]

See Ross's next post for corrected info. Nothing to see here....

 

[Ross]

Actually, the heater core connects to the 2 pipes sticking out of the lower part of the thermostat housing.

 

[David]

Actually, the heater core connects to the 2 pipes sticking out of the lower part of the thermostat housing.
View attachment 54923
Those red circles on the upper part are for the oil heat exchanger.

So not sure im getting this, what red circles ?

Picture of the top thermostat housing is as follows correct?

The two long pipes that are looped was for the heater core. By drilling the hole you can plug both long pipes and eliminate the loop.

 

[Ross]

Correct.
The red circle info doesn't apply anymore... same as your red lines on the previous pic.

 

[David]

Ok so I have to hit the drawing board again. I was going to the thermostat housing with the oil oil nipples. Not going to work snice its super tight and I cant get an fitting. So my idea now is to use the heater core loop for the oil cooler. The issue is I cant source the thermostat housing without the oil cooler nipples and also the water outlet housing. Want to get a new one incase I screw it up I have a replacement.

Anyone have a spare to sell or where to buy one?

 

[Desert Sasqwatch]

The LNF thermostat housing has only 1 small connection instead of the 3 connections that the LSJ has.

 

[David]

The LNF thermostat housing has only 1 small connection instead of the 3 connections that the LSJ has.
View attachment 54958

My LSJ has 4 connections, I want to see if i can switch to the 2 connections ( one return from driver side, 1 expansion tank). Then I could use the heater core nipples for my oil cooler.

 

[David]

You can use freeze plugs on your heater loop instead of extra work tapping and plugging them. Been that way on my Stalker V6 for 20 years now. You want the thermostat to stay closed to heat up the engine quicker then open to keep temperature regulated. The oil should heat up nearly the same rate as the water so I wouldn't worry about the oil cooler function. Make sure your thermostat has the jiggle valve or drill an 1/8th inch hole for continuous flow through system to help keep air pockets out. You could add a heater core into the system for more cooling if desired. Or use the heater loop for your new water to oil cooler tank.

If I would use the heater core loops for my water/oil cooler. I could plug the oem cooler ports. Im guessing I dont have to drill the ½" hole snice I would be using the cooler as the loop correct?

 

[Ross]

True. Moving the oil cooler from its' original connections to the heater core connections does move it from the cold loop to the hot loop.
The heater core circulates when the engine is cold and hot, the hot loop only circulates when the thermostat opens.
I don't see an issue moving it to the heater loop. I wonder if there is another ecotec thermostat cover without the extra oil cooler connections. I'm not sure if the LNF cover has the same 3 bolt pattern.

 

[David]

True. Moving the oil cooler from its' original connections to the heater core connections does move it from the cold loop to the hot loop.
The heater core circulates when the engine is cold and hot, the hot loop only circulates when the thermostat opens.
I don't see an issue moving it to the heater loop. I wonder if there is another ecotec thermostat cover without the extra oil cooler connections. I'm not sure if the LNF cover has the same 3 bolt pattern.

Yea the LNF cover has only 2 bolts. It looks like i would have to change the water neck housing to the LNF to be able to use the thermostat cover. My guess the best easiest option would be the thread and plug the LSJ cover.

Now tiu got me thinking, if I switch it to the heater core loops. Will the oil cooler not be as effective snice it won't be getting controlled by the thermostat?

 

[Dale E]

I don't believe using the heater loop for your extra oil cooler will make it less effective. You have enough extra oil capacity and the left side pod cooler that should be more than you need. At some point you will be less efficient. Using the water loop is done all the time with the Lamin ova style oil coolers.

You need the oil to be hot enough to burn off carbon sludge and to help with condensation of water vapors.

It's been hinted by some that since I am not a Goblin builder I should not post - so there's that! Take it or leave it - your choice!

 

[Ross]

The cool loop circulates coolant before the thermostat opens, then both loops circulate after the thermostat opens. Since both loops share the same coolant, they both get temperature control.

 

[David]

The cool loop circulates coolant before the thermostat opens, then both loops circulate after the thermostat opens. Since both loops share the same coolant, they both get temperature control.

Great,so doesn't matter what loop I use. Im going to try and 3d scanner the housing and design a new cover with new ports facing the rear so I can use AN fittings.

 

[David]

Ok so let me know if im crazy, the plumber inside of me is making me over think this oil cooler piping.

If both lines to the oil cooler are connected above the thermostat. How does the coolant circulate correctly through the oil cooler?
Even worse when the thermostat opens the coolant takes path of least resistance which will not be around the oil cooler.

Im assuming there should be a feed a return so the coolant circulates correctly. So like the heater core the coolant has the feed and return so it always circulating.

 

[Ross]

In your diagram, you have the colors backwards. The red arrow is the coolant after the radiator has cooled it. The cool coolant enters the oil cooler on your red line, and the hot coolant leaves on the blue line.

This picture is the inside of the thermostat top.
That 3/4" restriction (black circle) is key to making coolant flow thru the oil cooler.

When the 1" coolant tube enters the top of the thermostat (blue arrow), the coolant has 2 choices, a 3/4" hose to the oil cooler, or a 3/4" restricted hole to the top of the thermostat (black circle). So about half the coolant goes each way. The water pump is pulling water thru the thermostat, so coolant from the red arrow and the black circle will be pulled towards it.

You probably shouldn't cap off the oil cooler lines, rather put a 3/4" hose loop in there, or grind out that restriction.

 

[David]

In your diagram, you have the colors backwards. The red arrow is the coolant after the radiator has cooled it. The cool coolant enters the oil cooler on your red line, and the hot coolant leaves on the blue line.

This picture is the inside of the thermostat top.
That 3/4" restriction (black circle) is key to making coolant flow thru the oil cooler.
View attachment 54981
When the 1" coolant tube enters the top of the thermostat (blue arrow), the coolant has 2 choices, a 3/4" hose to the oil cooler, or a 3/4" restricted hole to the top of the thermostat (black circle). So about half the coolant goes each way. The water pump is pulling water thru the thermostat, so coolant from the red arrow and the black circle will be pulled towards it.

You probably shouldn't cap off the oil cooler lines, rather put a 3/4" hose loop in there, or grind out that restriction.

Excellent Thank you so much. I had the flow incorrectly and that the reason I wasn't grasping the flow. Now I see why the restriction on the 1¼ hose will help divert the flow. I currently have the oil cooler lines looped. If i would remove the loop the flow will drop. So I would have to bore the 1¼ to allow complete flow.

So now that I understand this a little bette. This will most likely be my path if possible.

- Plug the oil cooler line ports
- Bore the 1¼ to make it full port and allow full flow
- Tap both heater core nipples and use AN -10 lines to feed my water/oil cooler.
- Tap the expansion tank nipple and run AN-10 line.


What do you guys think? Sorry to be a pain in the butt.

 

[Ross]

I think your idea will work. If it was mine, I would leave the oil cooler lines stock, and if you don't like the look of the cabin heater loop, then modify the thermostat housing with a drill, and two 20mm? cap plugs.

 

[David]

I think your idea will work. If it was mine, I would leave the oil cooler lines stock, and if you don't like the look of the cabin heater loop, then modify the thermostat housing with a drill, and two 20mm? cap plugs.

Issue is I want to eliminate the rubber hoses and run stainless lines to my oil cooler. The way the oil cooler nipples are. There is no room for the AN fittings.

 

[Ross]

Then modify it the way you suggested. I like AN bling too.