When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
What I don't understand is your actuator closes the heat riser door correctly on a cold start...
When you manually remove the actuator hose (Simulating Engine Has Reached 180*+) the actuator rod extends to it's normal or home position opening the heat riser door.
No, the actuator should not make any noises but I still think you have a TVS switch not exhausting.
These switches by design are to pass vacuum from the top port to the 2nd port and then to the actuator in it's normal or cold position.
When HOT the TVS switch internally changes state closing off the vacuum flow to the actuator but the actuator and hose leading to it still has trapped energy (vacuum) that needs to exhaust somewhere and that is through the TVS switch exhaust port.
ok so I blew threw the TVS switch it was clear . Than I boiled water and got it to 180-190 degrees than I put switch in water for a 30 seconds I took it out and blew threw again and it was closed !! Could not blow threw it.
Grady, I'll send you the one off my car for the cost of shipping if you want to try it.
Let me know, I'll test it with my vacuum pump before sending it.
Have you tested yours with a vacuum pump? I don't remember.
That would be extremely generous of you Jeff very well appreciated
That would be extremely generous of you Jeff very well appreciated
It's no problem, it's sitting in my shop getting ignored. If it helps someone else get their car fixed I'm happy to send it off.
I'll go test it with my vacuum pump and see what it moves at, do you know how much vacuum it requires?
Well disregard that offer, mine's no good.
The vacuum pump won't move it and when I push the rod up and hold my finger over the vacuum port it still relaxes and returns to the open position.
You should be able to test yours that way to see if it holds vacuum.
Well disregard that offer, mine's no good.
The vacuum pump won't move it and when I push the rod up and hold my finger over the vacuum port it still relaxes and returns to the open position.
You should be able to test yours that way to see if it holds vacuum.
ok thank you just the same I appreciate your help and time .. I will try it but I think it has vacuum because at start up in the cold position it closes heat riser.. when she get to temperature 180 it doesn’t fail and open up unless I pull vacuum line than she opens
what is the temperature of the thermostat you are using? Yours should have been 195f, and if you dropped to a 180f like most people do, you may not be closing. Drop the switch the same amount or more than what you lowered tstat to. If you did..
ok so I blew threw the TVS switch it was clear . On a cold Switch GOOD, that is the switch normal position... Than I boiled water and got it to 180-190 degrees than I put switch in water for a 30 seconds I took it out and blew threw again and it was closed !!Could not blow threw it.GOOD but You only tested part of the switch function, the switch closed BUT did the switch ALSO exhaust? Remember, closing off the switch traps the energy in both the hose to actuator & actuator.
You don't know that because you need a vacuum pump for testing.
Remember your other tread me showing you how to test the switch with a vacuum pump?
You Own a C3,
Must haves are:
Assembly Manual
Service Manual
and a hand Vacuum Pump
A Cheep one works as good as the $80.00 one
Something like this that has the adapters.
what is the temperature of the thermostat you are using? Yours should have been 195f, and if you dropped to a 180f like most people do, you may not be closing. Drop the switch the same amount or more than what you lowered tstat to. If you did..
hmmmm.. I just changed it the owners manual said 180 the old one was 195 however I had the same problem with that one
ok so I blew threw the TVS switch it was clear . On a cold Switch GOOD, that is the switch normal position... Than I boiled water and got it to 180-190 degrees than I put switch in water for a 30 seconds I took it out and blew threw again and it was closed !!Could not blow threw it.GOOD but You only tested part of the switch function, the switch closed BUT did the switch ALSO exhaust? Remember, closing off the switch traps the energy in both the hose to actuator & actuator.
You don't know that because you need a vacuum pump for testing.
Remember your other tread me showing you how to test the switch with a vacuum pump?
You Own a C3,
Must haves are:
Assembly Manual
Service Manual
and a hand Vacuum Pump
A Cheep one works as good as the $80.00 one
Something like this that has the adapters. https://www.amazon.com/DASBET-Pressu...e%2C142&sr=1-6
Yesterday, board as heck I decided to test my other GM replacement switch and since I had both the spare actuator and switch still unboxed I thought I would test them together for a more visual effect.
This time I used my Fluke IR thermometer with thermocouple for a more accurate reading...
Started with water about 200* pulled a vacuum at the switch with actuator connected and waited until the water was around 189* before putting switch in water...
Notice, it only takes about +- 6" of vacuum to retract actuator rod...
Video is about 50 seconds long...
Yesterday, board as heck I decided to test my other GM replacement switch and since I had both the spare actuator and switch still unboxed I thought I would test them together for a more visual effect.
This time I used my Fluke IR thermometer with thermocouple for a more accurate reading...
Started with water about 200* pulled a vacuum at the switch with actuator connected and waited until the water was around 189* before putting switch in water...
Notice, it only takes about +- 6" of vacuum to retract actuator rod...
Video is about 50 seconds long... https://www.youtube.com/watch?v=vcog0b741A4
wow excellent video 👍 my problem is heat riser closes when cold , but when motor warms up to 180 the actuator doesn’t fail and open heat riser. Only when I pull off vacuum hose , and than it fails and opens., I changed thermostat and NOS TVS switch
Grady, I know what problems your having and the parts you have changed and will stay with you on this until it is resolved!
Please explain to me what YOU think happens to the trapped energy (vacuum) in hose and actuator when the TVS switch reaches 180+?
Last edited by bmotojoe; Mar 15, 2022 at 07:45 PM.
Grady, I know what problems your having and the parts you have changed and will stay with you on this until it is resolved!
Please explain to me what YOU think happens to the trapped energy (vacuum) in hose and actuator when the TVS switch reaches 180+ and closes ports 1 & 2?
thank you .. you have a valid point !! I think it should maintain pressure in the line but not enough to keep riser closed. I am getting a new actuator I will install it when it arrives
I still believe your either not reaching 180*F+ when car is warm or the new NOS switch is faulty.
Sure, you can heat it up in a cup to 180*F + and it closes the vacuum path but does port 2 exhaust through port 3?
I still believe your either not reaching 180*F+ when car is warm or the new NOS switch is faulty.
Sure, you can heat it up in a cup to 180*F + and it closes the vacuum path but does port 2 exhaust through port 3?
i hear what you are saying the only thing I can see that is different from the old switch to the new switch is the old switch did not have a screen on the exhaust port where as the new one had a little screen on it 🤷♂️
