Excessive control pressure (combines Inside the WUR and fuel cell height & CP)

[ramiro]

If it's so far up it is normal that the pressure is not rising because the bimetal has no effect like that , and thats also the purpose because you can now adjust the warm pressure to ~ 3,2 by tapping the fuel cell in and then you can lower the pressure down with the bimetal.

The idea is that the bimetal strip should have no effect when the engine has warmed up thats why you should tap it out to adjust the warm pressure to be sure that it won't mess with the pressure and only then adjust the cold pressure.

[Feather535]

I followed this procedure.  First I drove the pin for the bimetal strip up to be flush with the top of the WUR, then tapped the fuel cell down about about 2 mm above the top (starting at 4 mm), then tapped the pin for the bimetal down again.  Now I have 0.9 bar cold at about 3 C and 3.1 bar warm after 6 minutes with the heater plugged in and using a heat gun on the outside of the WUR for a few more minutes. Both settings are in spec for the temperature when I did this (3 C) and the model (California, 1977), so this should be good enough.

Now I need to put the WUR back in it's normal place and see how the engine runs, but that's a job for a warmer day!

[ramiro]

I hope that you measured the pressure and adjusted it to the around 3.1 bar before you tapped the pin back in, because if not it is possible that the bimetal is affecting you warm pressure and it could rise further on a hot engine (i made this mistake before knowing the procedure and nearly went crazy because the warm pressure was always changing).

[Feather535]

I hope that you measured the pressure and adjusted it to the around 3.1 bar before you tapped the pin back in

That's how I did it.  I had 3.2 without heat before tapping the pin down and 3.1 with heat afterward.  Seems good?

[ramiro]

Should be good then , i don't know if you have full throttle enrichment on the WUR if yes then this is the full throttle control pressure , so at no load it will be ~ 0.2 - 0.4 higher , because the vacum is pushing the control rod up.

You can use a vacum pump on the top vacum connector to replicate this without the engine running.

[Feather535]

Should be good then , i don't know if you have full throttle enrichment on the WUR

It does have full throttle enrichment.  Pulling vacuum makes the pressure drop.  I didn't record the pressure with vacuum, but it's moving in the right direction, so the mechanism seems to be working. 

Next step is to test it on the car with the engine running, but I'll need to wait for the snow to stop.  Can't even get to the garage today!

[ramiro]

The vacum makes the pressure higher and when the engine is at load there is no vacum in the intake so the control pressure will decrease.
The vacum port is at the top , the other at the bottom is just the vent port that goes before the throttle body.

[Feather535]

The vacum makes the pressure higher and when the engine is at load there is no vacum in the intake so the control pressure will decrease.

Of course.  I'll check it again.