V1 Ross's extended city, easy entry Goblin- 06 SS/SC, NW Arkansas

[mike_sno]

Paas means path. Sorry. I am in a rush.

The drawing is not a shop drawing of the coolant through the eninge. It's an oversimplified version I created in less than 5 min. It shows the plan you were describing above and I wanted to go as well: take the thermostat out and install the EWP after the radiator.

I did not intend to make the orange part the head cooling path. I don't know how the internal path of the cooling in an LSJ looks like. Orange is something unknown and is the connection between 1 and 3. Knowing that the inlet is at 2.

I didn't made a typo. It's the new layout with the EWP and the feeding IN at 1 and 2.

I can make a second drawing and return the arrow on 1 and make it an outlet. That's the difference to the stock LSJ. In that case my drawing would be wrong. Hope that makes it clear.

If the path from 1 to 3 is unknown. It might pass the head or it might not in which you pump the majority of coolant in 1 and out 3 and you get very little flow over the head and the cylinder.

I think it might be best to machine a small part and put it in between the thermostat housing and the engine block. This would block the flow completely in 1 and forces the coolant to go out 3.

Hope that makes now more sense.

 

[Ross]

You gave me an idea...
if I run hose from 1 to 3, then the coolant flow thru the engine would be the same as a stock water pump.
The EWP would pump coolant in 2, and 1 and 3 would exit to the radiator.
I guess it is a little different than stock, as 1 doesn't normally go thru the radiator, but the flow thru the engine should be the same.

To connect a hose from 1 is easy, as it is the red arrow on my old diagram. I would have to add a T fitting in #3. Then plug the orange arrow on the thermostat housing with a 1/2" NPT plug.

Oh wait, was that your point all along?

mike_sno said:
If you now feed coolant with an EWP in 1 AND 3.

This EWP redesign would feed coolant in 2, and out 1 and 3... just like stock water pump

 

[mike_sno]

I'm not sure that I understand your way.

I think a hose/Tee is way more complicated as a think piece of metal which just slides in between the thermostat housing and the block.
Down side, you would have no flow, maybe a small hole in that sheet which restricts the flow would be a compromise.

 

[Ross]

Here is the back side of the thermostat housing. The housing has a recessed O ring to seal against exit #1 which is machined flat on the engine block. If you want to block exit #1, just remove the steel pipe at the green circle, and put in a 1/2" NPT plug.

The water from exit #1 doesn't get to the purple arrow unless you run a hose loop from the red arrow to the orange arrow.
Some builders have eliminated this rubber loop by removing the steel pipe at the green circle, then drilling thru the aluminum at the white circle, then water can flow to the purple arrow side... then they put a 1/2" NPT plug in the green circle, and they plug the orange side too.
This modification would flow the water a few inches away from the thermostat, so this will result in the thermostat responding slower.

The stock engine water flow normally has the water exiting from port #1, whether the thermostat is open or closed, it is always an exit.
My new EWP idea it to keep this as an exit from the engine.
By connecting a hose to the red pipe, then run this hose to a T near port #3, it will flow water out to the radiator.
Then block the orange hole with a NPT plug.

If you don't want to run a hose to exit #3, then leaving it with the goblin rubber loop will make port #1 an inlet to the engine. You could restrict the rubber hose if you are worried about too much water flow thru it. Or just drill a small hole at the white circle, and block the red and orange ports. That also makes port #1 an inlet to the engine. Both your method and mine will probably work... according to my mad scientist mind.

 

[mike_sno]

I assume the second picture is one where the hole in the white circle is drilled?

OK, I think now I understand what you want to do with the Tee.

I guess, judging just by the different diameter, if I just remove the thermostat and connect the oil cooler to the rubber loop it should work. Probably water would flow backwards, but I think the majority of the flow would go the regular way.

If I do the Tee as well, I would go out the red arrow, over the oil cooler and tee at the point you mentioned. I wod just remove the orange pipe and block that off.

 

[mike_sno]

I honestly think my idea with blocking 1 isn't good at all. Do you have a Tee which connects the big coolant hose and accepts a smaller one from the oil cooler?

 

[Ross]

Yes. In this post, Rauq found a Dorman 627-006 Radiator Coolant Hose T fitting.
a 1 1/4" hose tee to splice into the radiator incoming line.

 

[Ross]

I assume the second picture is one where the hole in the white circle is drilled?

Yes.

OK, I think now I understand what you want to do with the Tee.

I guess, judging just by the different diameter, if I just remove the thermostat and connect the oil cooler to the rubber loop it should work. Probably water would flow backwards, but I think the majority of the flow would go the regular way.

Why would the water flow the regular way?
The regular way exit #1 has high pressure behind it from the stock water pump pushing water into #2, and exit #1 leads to the purple, which is the low pressure side of the water pump.
If the EWP is up at the radiator, then the blue and purple arrow are high pressure from the EWP, and only exit #3 is low pressure to the EWP.

If I do the Tee as well, I would go out the red arrow, over the oil cooler and tee at the point you mentioned. I wod just remove the orange pipe and block that off.

I think I will also take coolant from the red arrow, over to a water cooled turbo, then over to Tee into exit #3. Also I would block off the orange pipe.

 

[ah.b.normal]

Other thoughts about my new EWP (Electric Water Pump) system:
- I won't be able to purge the air from the coolant system using my red neck method. I will have to use the vacuum pump method.
- removing the water pump, balance shafts, sprockets and chain is mostly to reduce rotating mass. You could just grind off the fins on the impeller, to stop running the coolant pump.
- most builders modified the coolant pump and coolant pipes to add the EWP... but my method just removes the thermostat, and modifies the coolant pump. I considered removing the stock thermostat housing... but it is easier to leave it all stock.
- If you want to remove the rubber hose loop, you could modify the thermostat housing.
from this View attachment 50819 to this View attachment 50817

In the stock engine, I wonder if the Ecotec design engineers put that aluminum coolant pipe under the exhaust as a way of heating the coolant... it is the only coolant loop when the engine is cold, and the exhaust is the first thing to heat up on a cold engine.

You could probably sell those modded thermostat housings. Then again, than you for the excellent pic and inspiration. Nobody needs a rubber hose loop with hose clamps VS plugs! It's just another spot to break/leak.

 

[Desert Sasqwatch]

Or an opportunity to insert a heat exchanger, if you reside in places that are as hot as Death Valley for too many times every year.

 

[mike_sno]

You could probably sell those modded thermostat housings. Then again, than you for the excellent pic and inspiration. Nobody needs a rubber hose loop with hose clamps VS plugs! It's just another spot to break/leak.

In a stock set up the rubber loop is still necessary.

 

[Ross]

In a stock set up the rubber loop is still necessary.

Or you could install a modified thermostat housing...
Some builders have eliminated this rubber loop.

 

[Gtstorey]

I think there have been issues with overheating when simply capping the lines for the heater loop.

 

[Ross]

I think there have been issues with overheating when simply capping the lines for the heater loop.

True. That is why you either need to keep the rubber loop, or modify you thermostat housing.

 

[Ross]

The two Dorman 565-100 30mm plugs arrived today, and were installed. Modified water pump done!

Now the rest of the engine is getting torn down. No water pump, no balance shafts, no oil pan, no valve cover, no exhaust, no supercharger, no exhaust cam ...

 

[mike_sno]

Why would the water flow the regular way?
The regular way exit #1 has high pressure behind it from the stock water pump pushing water into #2, and exit #1 leads to the purple, which is the low pressure side of the water pump.
If the EWP is up at the radiator, then the blue and purple arrow are high pressure from the EWP, and only exit #3 is low pressure to the EWP.

I think with the EWP, removing the thermostat and having the oil cooler in the rubber loop the water could go out the orange opening of the thermostat, then through the oil cooler and get into #1. The coolant would flow backwards in compare to the stock water pump.

I think I will also take coolant from the red arrow, over to a water cooled turbo, then over to Tee into exit #3. Also I would block off the orange pipe.

That makes sense. I will block off the orange outlet of the coolant housing and spare it if I go turbo later. I am planning of going out the red tube, then through the oil cooler and return to the Tee. The Tee installed behind the engine, on the way to the cooler. For testing, I will leave this hose going in a bucket and see how much flow comes out of it.

I just ordered all parts (pump, controller, pump pigtail and temperature sensor). Missing the temperature senor pigtail and tee.

 

[mike_sno]

Or you could install a modified thermostat housing...
Some builders have eliminated this rubber loop.

True, I just wanted to avoid that other builder think they can, in a stock set up eliminate the rubber loop. What @Gtstorey said is actually a proof that my idea with blocking off #1 was terrible.

 

[Ross]

Congrats Mike, you have bought all the expensive parts for the EWP. I agree with all your points, so I think we have a good understanding of the cooling system.

@Dale E pointed out that we could use freeze plugs to block the thermostat housing, rather than having to thread and install 1/2" NPT plugs. I measured my thermostat housing metal pipe around 19mm, and can find some freeze plugs that probably would work. I would measure the aluminum housing more accurately if I had the metal pipe pulled out.

Those freeze plugs have a range of
0.740" - 0.755" or 18.796mm - 19.177mm

 

[Ross]

So port #1 does just get coolant from the head. The path takes it to the circled blue port. All the blue passages in the block are coolant, while the orange ports are oil passages.

I decided to undo the head bolts by starting at the outside bolts, then circling inward. When I got to the last head bolt (the one the flex bar is on) it didn't want to undo. I wish I owned a 15mm impact socket... as I broke 3 of my 15mm sockets. Since I was down to my last 15mm, I decided to torque the 5 head bolts near it, then it finally broke loose. I probably way overstretched that last bolt... hopefully not the head too. I have new ZZP Ecotec Head Stud Kit, ZZ-ECT-HSK, so I am not needing the old head bolts.

A visual inspection of the cylinder bores shows no signs of vertical scratches, and no wear lip at the top. Pretty good for an engine with 200K on the odometer. I see cylinder #2 has exhaust valves that are a little darker than the other valves. It may have been running a bit rich in that cylinder? Or maybe that injector isn't misting fuel very well.

 

[mike_sno]

So port #1 does just get coolant from the head. The path takes it to the circled blue port. All the blue passages in the block are coolant, while the orange ports are oil passages.
View attachment 50867 View attachment 50868

OK, thanks for keeping an eye on the water path and help to solve the myth. Once you posted the head picture you clearly can see the water path. I assume your current theory is that when the engine is cold you only have flow on the head? I'm still not sure if the #1 just gets the head return. Look where the mechanical water pump feeds into the block. Why can't the water go in that port, around the cylinder, in the head and then either out port 1 or port 3 at the top of the head?
I guess it also doesn't really matter as long as we have sufficient flow in all channels.

I decided to undo the head bolts by starting at the outside bolts, then circling inward. When I got to the last head bolt (the one the flex bar is on) it didn't want to undo. I wish I owned a 15mm impact socket... as I broke 3 of my 15mm sockets. Since I was down to my last 15mm, I decided to torque the 5 head bolts near it, then it finally broke loose. I probably way overstretched that last bolt... hopefully not the head too. I have new ZZP Ecotec Head Stud Kit, ZZ-ECT-HSK, so I am not needing the old head bolts.
View attachment 50869

Those bolts are single use. When I did my head I used this unbolt and rebolt pattern. Worked flawless. I was scared when torqued the head bolts. They scream

Regarding the one cylinder which might run rich or lean, would be nice if we had an o2 sensor at each cylinder. I read that usually the cylinder at the end of the fuel rail runs lean, due to less fuel pressure. An issue to be avoided with the boost reference fuel pressure system installed behind the fuel rail.

Cylinder Head Replacement — 2007 Chevrolet Cobalt L4-2.0L SC Service Manual | Operation CHARM

Detailed repair manual for the 2007 Chevrolet Cobalt L4-2.0L SC.

charm.li