Upgrade thermostat

[mottofreee]

We found that two polka dots ( 60C ), is warm the hose what go to radiator=> thermostat unit compromise and anyway not working parameters.
The car remained as so and I bought another thermostat.
From what recounted TK, Gates thermostat is removable. I ordered component of the net and arrived in 24 hours (GATES TH40390G1). https://plus.google.com/photos/11282...18205146693954
In the 25th hour it was opened. https://plus.google.com/112827018205...ts/5bEwWuBm6Jb , https://plus.google.com/photos/11282...18205146693954
Flange which is pressed on wax unit is steel (not stainless steel). I want to replace it with one of PTFE. https://plus.google.com/photos/11282...18205146693954
The bypass valve remove it , depending on the functioning cooling systems at high temperatures (in summer) will reverse the decision.
I'm open to any suggestions.

[tolsen]

Seat is slightly distorted on these Gates thermostats so I made a special lapping tool to correct that.

Your PTFE disc should work provided it can make a positive seal against seat.

Fit a 9 mm restrictor in bypass.

[mottofreee]

I will fit the bypass.
Seat deformation can be corrected by inserting a stainless steel bushings (similar to the cylinder head valve seats).

[tolsen]

Making a new disc is more work than one would think so initially I tried improving on the existing disc by turning it true on a lathe, removing check valve and sealing its hole:

Above was quite an improvement compared to how it was but it still leaked more than the original Wahler, mainly because seat is not perfectly true and round. Max gap between seat and disc (without O-ring) is 0.25 mm. I therefore manufactured a special lapping tool to sort this out.

I then made a new disc out of marine bronze:


The o-ring used is a 2 mm diameter profile of unknown type and material. Ideally I should use Viton.


O-ring groove is cut perpendicular to the 35 degree angle seat of thermostat housing chapeau. Dressed o-ring groove with a 1.7 mm diameter Lidl Dremel equivalent ball head bit.


I removed casting flash from the housing and ground the ends of the spring:


Assembled thermostat with L shaped locking pin out of 1.6 mm stainless steel TIG rod in original pin hole:


Initially I was worried the o-ring would either overcook or drop out of its groove in disc but has performed remarkably well after two years of service.

[tolsen]

Seat lapping tool:


Use valve grinding paste and stick with suction cup to lap in seat. Just like lapping in valves.

[mottofreee]

The seat deformed of production or the closure of thermostat housing?
Viton?From this material is sealed the hydraulic cylinders are made. Wahler thermostats were the main valve from VIT. (e.g. VW Touareg 2004) .

[tolsen]

Plastic mouldings always deform a wee bit.

[mottofreee]

So not reclosing the lid, understand . Material deformation caused cooling ?
There is a company here (Cluj Napoca) to produce custom rubber parts . I see if it working and for Viton .

[tolsen]

Easy to check if seat is perfectly true. Place a round metal disc against seat and you will see gaps. My Gates thermostat had 0.25 mm gap. Fixed after 10 minutes of lapping in seat with special tool seen in one of my previous posts.

[mottofreee]

Dacia Logan thermostats original rubber the thaler . For Logan 1 as the Smart thermostat is . Termostat thaler rubber has Freelander 2.0 diesel, but to oil cooler (no. Thermostat PBM100040).
Complementing to the main thermostat, the system can be introduced and heating thermostat matrix . The problem is that I have not found one to 50 Celsius but I know where to use : construction machinery, karts and ATV / quad.
For the construction machinery are too high.
For the karts are too small.
The ATV / quad are suitable but I'm looking for ...
I know the 60C (at Loncin, Bashan, Kinroad ,etc ... made in China) but this thermostat should be located for easy access (at Smart?) and in the front, away from the engine.

[tolsen]

Thermostat for Kangoo I with F9Q 790 engine has rubber disc and seals 100%. Also very easy to replace wax element on this thermostat.

[tolsen]

You can even modify thermostat wax element and change its opening temperature. I used dubbin wax when overhauling a discontinued thermostat for a Crescent outboard. Has since performed fine for 8 years.

[mottofreee]

Disc thermostat is ready to use -- can be used a oil seal . If oil seal material is Viton when they are equipped with stainless steel springs . Active side is rear bevel .

The price of a oil seal with Viton is below a pound.

[tolsen]

Photos please!

[mottofreee]

I have not found a store opened to buy a suitable Oil Seal. But last the company visit, I get something similar (functionally similar).
The Viton washer between two metal washers. https://plus.google.com/photos/11282...18205146693954
The drip test is ok. The test lasted only five seconds, the seat is unrectified.
I also did a restrictor.

https://plus.google.com/photos/112827018205146693954/albums/6233381648109436609/6233382530569926898?pid=6233382530569926898&oid=112827018205146693954

https://plus.google.com/photos/112827018205146693954/albums/6233381648109436609/6233382768515858802?pid=6233382768515858802&oid=112827018205146693954

Material - PTFE graphited