Bosch WUR 0438140004

[celestialpen15]

I have a 1987 Volvo 740 with a B200e engine and I am in need of a new WUR. If anyone has one that they would be willing to part with that would be great

Thanks

[Moomoo]

Just out of interest, WTBH is that, when it’s at home?🧐😁👍

[940volvoman]

Wageningen University & Research - WUR!!!!!(googles first answer.....)


Also known as a warm up regulator, what ever that is.....

[Chris1Roll]

Just checking, I assume you have actually tested the pressures, and also made sure that the filters on the ports aren't simply clogged with 37 years of detritus?

They can be rebuilt, they are actually quite simple devices (not that I have done it, but I'd certainly try)
If you look up 'grey goose' on YouTube, there a guides on there if you want to give it a go yourself or I believe he also does it for customers as a sideline (but don't quote me on that)

Moomoo - the warm up regulator, or control pressure regulator is basically a metal diaphragm with fuel flowing across it and with an electrically heated bimetallic strip in it.
On a cold start (and I so hope I get this the correct way around but either way you'll get the principle) the control presure regulator will reduce the fuel pressure acting on top of the piston (the control pressure) in the fuel distributor, thereby allowing it to move further up and allow more fuel to the injectors for a richer mixture during warm up.
As the bimetallic strip heats up (and also with engine heat) the control pressure regulator will pass more fuel, increasing the control pressure on top of the piston, counteracting its upward movement and so reducing the fuel injected ti the normal running mixture.

Some cars also had a vacuum port on the regulator, I assume to enrich the mixture at wide open throttle.

[Moomoo]

Originally Posted by Chris1Roll

Just checking, I assume you have actually tested the pressures, and also made sure that the filters on the ports aren't simply clogged with 37 years of detritus?

They can be rebuilt, they are actually quite simple devices (not that I have done it, but I'd certainly try)
If you look up 'grey goose' on YouTube, there a guides on there if you want to give it a go yourself or I believe he also does it for customers as a sideline (but don't quote me on that)

Moomoo - the warm up regulator, or control pressure regulator is basically a metal diaphragm with fuel flowing across it and with an electrically heated bimetallic strip in it.
On a cold start (and I so hope I get this the correct way around but either way you'll get the principle) the control presure regulator will reduce the fuel pressure acting on top of the piston (the control pressure) in the fuel distributor, thereby allowing it to move further up and allow more fuel to the injectors for a richer mixture during warm up.
As the bimetallic strip heats up (and also with engine heat) the control pressure regulator will pass more fuel, increasing the control pressure on top of the piston, counteracting its upward movement and so reducing the fuel injected ti the normal running mixture.

Some cars also had a vacuum port on the regulator, I assume to enrich the mixture at wide open throttle.

It is ,as I suspected, Chris!😂