Upgrade thermostat

[tolsen]

Be patient. Bleeding air out of system takes longer after removal of check valve in thermostat disc.

Keep expansion bottle cap off throughout bleed process.

Lift coolant temperature sensor until coolant leaks out, then push back in place and secure with clip.

Check valve at bottom of expansion bottle could be stuck close. Confirm the 8 mm diameter green plastic ball floats and moves freely only kept in position by the black retainer. Tap side of expansion bottle to confirm. Purpose of this green check valve is to allow air to flow from top of radiator into expansion bottle but stop flow of coolant from inside expansion bottle to radiator which would lead to unnecessary loss of heat.

[tolsen]

Above photo shows the internal parts of check valve inside expansion bottle. The green plastic ball floats in the coolant and is held in place by the black plastic piece vertically fitted inside expansion bottle at top of "elbow".



"Elbow" is seen at bottom left side of expansion bottle. Although being part of the expansion bottle molding, coolant cannot flow from elbow to expansion bottle or vice versa. A small vertical bore containing above mentioned green check valve is the only communication between elbow and expansion bottle.


When filling up a dry cooling system, coolant enters and air is purged out of system as follows:

1. Coolant is filled into expansion bottle. Cap must be off and level needs be maintained requiring frequent top up as air is being purged out.
2. Coolant flows out of expansion bottle through bottom hose barb marked with a pink arrow in above photo. Coolant flows into return hose from radiator and gradually fills radiator and engine block.
3. Air in radiator is purged through green check valve in bottom of expansion bottle.
4. Air in engine block and cylinder head must be purged by lifting temperature sensor on thermostat housing.
5. Air in heater matrix circuit is purged when lifting temperature sensor on thermostat housing. Coolant enters from thermostat housing and purges air out of heater matrix circuit through return hose connected to top right hand side of expansion bottle.
6. Air in rear end of circuit from thermostat housing to expansion bottle is purged through the check valve fitted in disc of thermostat. Of course if thermostat has been modified by removing this check valve, then air here cannot be readily purged out of system. Not really a problem. One can purge by disconnecting outlet hose at thermostat housing or repeat standard bleeding procedure a couple of times after engine has come up to operating temperature. A good alternative is vacuum bleeding.

Left and right in this context refers to the photos as seen, not left or right of vehicle.

[Ron]

hi Im new to this site so please forgive me if i have asked this question in the wrong place .After reading your comprehensive post above I feel you could well be able to help me . Briefly my quandary is this, my 450 takes a long time to reach 3 blobs on temperature gauge and the cabin does not warm up could this be a faulty engine stat as i suspect or something else the control lever appears to move the gate as it knocks at either end of its travel.sorry for being so long i have just registered under Ron Thankyou

[mottofreee]

What Smart model are we talking about? Coupe or convertible?
What is the distance traveled until 3 blobs appear?
Possible causes (for coupe):
1. Thermostat, thermostat, thermostat - is replaced ; when replacing, I recommend mounting a Tolsen restrictor directly on the thermostat.
Less likely:
-air in the installation - when was the antifreeze last replace ?
-a defective hose - check if there is movement in the expansion vessel when you accelerate the engine - extremely rare defect
-inappropriate antifreeze level - rare.
The convertible is natural so if there are negative temperatures outside and the coupe heats up slow in winter.
This is a general answer, more precisely it is after feedback.

[mottofreee]

After a few hundred km and ~ 3 weeks began to wonder what we did wrong.
Cooling system capacity is 4.5-liter but I used 6l.
Only vacuum have not tried, but it will come.
I found in the attic a old aggregate fridge, but functionally ; they want to use it as a pump. https://plus.google.com/photos/11282...18205146693954
Some fittings and a rubber washer will form adapter for expansion vessel. The connections with 5/32 "parflex.

https://plus.google.com/photos/112827018205146693954/albums/6243270993792768337/6244158226534744930?pid=6244158226534744930&oid=112827018205146693954

Now, the passenger warming is not the biggest problem but must be solved.
Outside it is relatively warm and the engine is 3 dots in less than 4 km .

[tolsen]

I changed the thermostat, one dot in 400 m @ 0C, two dots in 2km @ 0C and three dots in 3,8km @ 0C degrees ambient .








On this occasion, I changed and antifreeze. High front, airy but still do not have heat. To remedy, I want to inject directly antifreeze in the radiator heating, suspect the a cushion of air.

Did you get all air out in the end?

[tolsen]

After a few hundred km and ~ 3 weeks began to wonder what we did wrong.
Cooling system capacity is 4.5-liter but I used 6l.
Only vacuum have not tried, but it will come.
I found in the attic a old aggregate fridge, but functionally ; they want to use it as a pump.

Some fittings and a rubber washer will form adapter for expansion vessel. The connections with 5/32 "parflex.

Now, the passenger warming is not the biggest problem but must be solved.
Outside it is relatively warm and the engine is 3 dots in less than 4 km .

Still no heating inside cab?

[mottofreee]

Today I put a oring but in test proved too great; I replaced with a suitable oring but test only tomorrow.

https://plus.google.com/photos/112827018205146693954/albums/6243270993792768337/6244557843963958514?pid=6244557843963958514&oid=112827018205146693954

https://plus.google.com/photos/112827018205146693954/albums/6243270993792768337/6244558067644105458?pid=6244558067644105458&oid=112827018205146693954

Not yet heating cab .
The problem is that it freezes the windows on the inside, from breathing. Will help with silica gel dryer?

[tolsen]

Take an old sock.
Darn any holes.
Fill with coarse rock salt.
Tie a knot in sock to hold salt in.
Use sock to keep windows clear of ice
by rubbing sock against glass.

[heinkeljb]

Do any of the radiator hoses get hot? The ones from the Thermostat on the engine that run under the car to the radiator at the front? If not then most likely reason is a blocked pipe - maybe with air, but maybe with something else.

Did you drain the system completely when you started doing this work or just to the point that you could take the the thermostat off?

Unless you get the glass to be above freezing both on the inside surface and the outside surface you will always have condensation / freezing on them unless there is no water in the air! Put a dehumidifier in it - even Silica Gel will help reduce the amount of water in the air, but it takes time to do so.

John

[mottofreee]

Tolsen,the perfect solution! Thank you .

Hose between radiator and water pump is warm when the thermostat is open.
The expansion tank is hot.
Hose between heater matrix and expansion tank is hot, but only flowing over 1200rpm.
I checked if it fits the adapter expansion tank - the new oring is too high and should be stocky to match. At the preliminary test (short test) does not escape pressure.

I want to follow the following procedure:
- covering the 10km to warm the engine well
- The vacuum the system expansion tank on the filler cap with the engine running.
- Vacuum expansion tank , on the filler cap with the engine running.
Meanwhile let the engine run at idle.
These days is lukewarm ( 5 ° C ) .

[mottofreee]

Meanwhile, I worked with pump compressor fridge; result -only pump burned.

https://plus.google.com/photos/112827018205146693954/albums/6243270993792768337/6249692593264570994?pid=6249692593264570994&oid=112827018205146693954

I made another pump of a compressor 7 CFM. In the current configuration can 27.5 inchHg maximum in 10 seconds.

https://plus.google.com/photos/112827018205146693954/albums/6243270993792768337/6249693127313688098?pid=6249693127313688098&oid=112827018205146693954

I used than 25inchHg namely:
- I drained all antifreeze
- Opened hose from the thermostat (which goes to the cockpit)
- I opened the hose coming from the passenger compartment (in the expansion vessel) and introduced in this a hose water at low flow for 20 minutes
- Drained water and mounted everything
- Install the new adapter and the vacuum the circuit

https://plus.google.com/photos/112827018205146693954/albums/6243270993792768337/6249698799827178754?pid=6249698799827178754&oid=112827018205146693954

- The vacuum closed and open valve antifreeze.

[heinkeljb]

This is getting very complicated for something which should just be the case of mixing up the required ratio of antifreeze and water, pouring it in slowly and allowing the engine to warm up and then releasing the air locks which may or may not have formed.

Are you sure your water pump actually works correctly?

John

[tolsen]

Something is wrong either he does not bleed right or there is a hole soewhere letting air in. Perhaps he should try making his glycol mix using holy water?

[mottofreee]

Less probably ,had to warm the engine quickly if water pump malfunction.
At summer I to know - want to unravel the whole pump, have a leak somewhere.
Holy water not help but spiritually - Smart has a soul? I do not think so ... here do not help.

[tolsen]

I am sure my Smart has soul. It got up to 3 blob operating temperature after only 4 km of spirited driving yesterday.

[10:45PM]

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