I have a magnificent TP carby/manual in great condition, but I am lacking one working component, namely, the thermal valve controlling the AAP. Has anyone any idea where such a valve may be purchased? Local and nearby wreckers cannot help.

That's the problem with older cars, parts availability.
Is the valve stuck open or closed? if it affects drive ability hot or cold, try being smooth on the accelerator pedal.

Hi TB,
It may be possible to substitute the AAP thermal with another 3 port thermal valve. It may also be possible to use an electric solution using a thermal electric switch in conjunction with a valve like the airconditioner idle up solenoid.
The piping diagrams I have dont say much about the AAP thermal valve. Whether it blocks or passes manifold vacuum to the AAP thermal when the engine is colder or hotter is not clear. We need to know this. My guess is that the AAP thermal allows extra fuel to be injected when the engine is cold and to be blocked when the engine warms.
As MadMax says, is the non functioning valve a problem; I believe there is a solution but it wont be 'Stock Standard'
Hope this helps,
rumpfy.

Auxiliary Accelerator Pump (AAP)
The Auxiliary Accelerator Pump is provided to
improve driveability while the engine is still cold. AAP
is controlled by a thermo-valve and intake manifold
vacuum and operates in the high load range while the
coolant temperature is low (below 65C).
The thermo-valve is of the bi-metal type and is
mounted on the intake manifold. The valve opens when
the engine coolant temperature is below 65C and
allows the manifold vacuum to affect AAP chamber
(A). The valve closes when the coolant temperature
exceeds 65°C to shut off the manifold vacuum and stcp
the operation of the AAP.
The manifold vacuum operates o n AAP chamber
(A). When the diaphragm moves to the right, the fuel
pushes check valve 1 open, and flows into and fills
chamber (B). When the throttle valve opens quickly
and the vacuum in chamber (A) lowers, the diaphragm
is pushed to the left by spring force. As a result the
fuel in chamber (B) pushes open check valve 2 and
squirts into the carburettor, enriching the fuel mixture.
refer Fig. 20.

Hi Taubada. Welcome to the mystery world of carburettors. Rumpfy and I have been having long discussions about ours but haven't touched on this subject yet.

Do you know where the AAP thermo valve is located and what it looks like? I don't and I just recently replaced my inlet manifold with a brand new one. I didn't come across it during that exercise and I was very thorough. According to the factory workshop manual and as just posted by Vee, the AAP thermo valve is a bi-metallic strip type and is mounted on the inlet manifold.

It should be possible to find it by following the vacuum line from the AAP. I just had a look under the bonnet and tried to do that but can't see a thing without removing the air cleaner. I'm about to head off for Tamworth, so don't want to do that right now.

If you refer to the picture of my carby in post 14 of this thread http://www.aussiemagna.com/forums/showthread.php?t=100698&page=2, you'll see a red arrow where I was pointing out the connection for the secondary diaphragm vacuum line. A couple of inches above that line, you can see a vacuum line that I think is the one from the AAP. It goes to the chamber that houses the wax pellet thermo device that turns off the automatic choke.

I will have a look tomorrow but I have to head off to Tamworth now.

I just took off my air cleaner and had a look. I was wrong. The vacuum hose I referred to in the photo of my carby does NOT come from the AAP. It comes from (or goes to) a connector at the base of the carby. I haven't worked out yet what that's for.

However there's a good reason I didn't find the AAP thermal valve on mine. Autos don't have them. That made me curious why I didn't notice one on my new inlet manifold, or at least a place where it would go. In fact I did notice but didn't realise then what the hole was for. I had to find a threaded metal plug to seal the hole off. Our helpful toyota dealer eventually found a sump plug for me with the required thread and diameter.

I have just found a diagram in the workshop manual that shows what the AAP thermal valve looks like and gives an idea of its location.
http://users.tpg.com.au/acheson1/images/AAP.JPG

Here's a photo of my manifold showing the hole that I had to plug. That location seems to correspond with where the aap thermal valve appears in the above diagram.
http://users.tpg.com.au/acheson1/images/MFOLD.JPG

So, I think any wrecker who has a manual trans. TP or TN should be able to find one for you if you show them where to look for it.

Taby,
Vees description makes a lot of sense. The normal thermal valve 'CLOSES' at 65 deg C; and the AAP thermal closes at 65 C also; BUT there is a difference.
Thermal valve: below 65 C Port 1 and port 2; open to atmosphere
Thermal valve: above 65 C Port 1 and port 2; closed
Note that Port 1 and port 2 are isolated from each other when closed

AAP Thermal Valve: below 65 C Port 1 and port 2 connected together and isolated from atmosphere.
AAP Thermal valve: above 65 C Port 1 and port 2 Isolated from each other and isolated from atmosphere.

SO; a normal thermal valve has the similar construction to the AAP valve. To use a Thermal valve as a AAP valve, you need to block the atmosphere port on the thermal valve. The other port on the Thermal valve is the one that controls the AIJ valve. Just block this off.

There may be something about the construction of the valve that means this suggestion wouldnt work.

There is another possibility.
The normal thermal valve has atmosphere when below 65 C. There is a vacuum line to the air cleaner and there is a thermal switch in the air cleaner which opens to atmosphere at an AIR TEMPERATURE about 20 deg C. This line controls the air preheat from the engine inlet air flap. The bimetal strip in the thermal switch has a bleed in the line to the manifold and this bleed limits the air flow into the manifold. The line between the thermal switch and the vacuum motor which operated the flap in the air cleaner inlet goes from 'manifold vacuum' when cold, to 'atmosphere' when hot (20 deg C). This line could be used to control an additional 'Purge valve'. This purge valve is the same as the one used at the cannister outlet.
The purge valve has 3 ports. The small one at the bottom turns the purge valve ON or OFF. Another purge valve port connects to the manifold and this port would connect to the manifold also. The third port is a large diameter port but this could be used to connect to the AAP port on the carby.
The problem with this suggestion is that the AAP may be disabled at a lower water temperature than normal. BUT, my experience with the TM carby model was that the engine would starve slightly for fuel when cold but this effect was quickly overcome as the engine warmed slightly.

Hope all this helps. Of course, it is ALWAYS better if you can get the right part; BUT; its not impossible to do some alternative.
To do all this would require checking over the proposal with a vacuum gauge.
Rumpfy

i know where to find some thermal valve's down here . i have seen a number of carby cars at wreckers ill check price's for you . or you can ring them and i will pick up and post for you .

Just bypass it.
It's not integral to the operation of the car.

Save you hunting for a dinosaur.

Mine was bypassed from the day I drove it.

Thank you all for the advice and assistance. I know that such parts are unessential, but if I can get them it makes my old darling (owned since new) complete. Thanks again

Magnaman89. Thanks for the offer. I would be quite happy to purchase a valve if you can find one.

hey mate just saw this i'll get one tomorrow .

checked three gen1 manual carbys today .no thermal valve found 1 on a tr but the dickhead broke it getting it off. ill go to a mate's wreckers tomorrow.

Thanks for the offer Magnaman89. If you have a phone number or two I will ring them.

I have a magnificent TP carby/manual in great condition, but I am lacking one working component, namely, the thermal valve controlling the AAP. Has anyone any idea where such a valve may be purchased? Local and nearby wreckers cannot help.
Thats the one under the carby inlet manifold cam chain end of the motor is it?? I think i have a couple i will be down home next week to check if you want? They are TN series AUTO but should be the same i would think.Vee

Vee,
Tauby wants the 2 port AAP thermal valve and NOT the three port thermal valve which was fitted to both auto AND manual magnas. The 2 port was manual only.
Maybe Astron boy can help!
rumpfy

Cannot you simply block off one of the 3 Ports.....as i assume that is what they would have done if it is fitted to both Manual and Auto?? Vee

vee,
My understanding is that the three port valve, when cold, has the three ports OPEN TO THE ATMOSPHERE PORT. When the engine temperature rises to 25 degree C, one of the ports closes to atmosphere and blocks itself from the other ports. When the engine temperature reaches 55 to 60 degree C, the remaining two ports close off from atmosphere and from each other. With the two port valve, it has two ports which are connected to each other when the engine is cold and when the engine reaches 55 to 60 degree C, the two ports close and block any connection to each other. At no time does any port on the two port valve become open to atmosphere.
I have never seen either of these valves but my guess is that they are of a similar design.
My suggestion, is to close off the atmosphere port of the three port valve, and then to block off the 20 degree C port. This will leave two ports which are connected together at temperatures below 55 to 60 degree C, and are closed to each other above this temperature.
From Taubs point of view this arrangement may not be what is required because I think he wants his car back to 'original stock standard'. BUT, if it is too hard to find an exact valve, then my suggestion may be OK.
The two port valve couples manifold vacuum to the AAP when the engine is cold, and blocks manifold vacuum when the engine is hot. Manifold vacuum activates the AAP and 'no vacuum' blocks its action. The AAP squirts additional fuel to the engine when it is cold, the fuel being supplied when the normal accelerator pump operates.

I note in the gregorys? manual, it is remarked that care needs to be taken in unscrewing these valves because of the possibility of breaking them. Magnamans post #13 is proof positive of what happens. The three port valve I imagine is more common then the two port type. Not having seen either valve, I cant say how would be the best way to block the ports.
Hope this helps,
rumpfy