Bikeartist1

Lol go back, not sure.. I've read articles on k jetronic til I'm blue probably in excess of 100 pages and still not an expert yet but hopefully getting there.I'm willing to bet the flow is up to par only witnessed by eye when I pulled in tank pump out thinking it was causing a restriction in pressure because of filter on end of pump. I installed later model tank fitting with strainer and no pump. Obviously my pump doesn't need back up pump with the pressures I'm seeing.Just a quick thing I noticed while checking for blockage upon opening the fitting at distributor from wur when wur was blocked I did have some fuel coming out of distributor which I assumed was due to no pressure coming from wur line to counteract.Great article by the way it's a shame you forgot to take some pics which the Ferrari article covered. Were getting there!

jpitman2

Try the flush trick by bridging the pump relay, and loading the gas with berrymans or similar, allow to run for as long as you can stay near by....with an extinguisher! then see what control you get. In fact if you leave a guage fitted to WUR line showing control, you might see a change in reading ?
jp

Bikeartist1

I have 1 bottle of cleaner premixed into gas in tank roughly 4 gals the problem is car won't run for more than start up maybe at best 20 seconds the only way I have achieved it running for maybe a couple minutes at a time is by opening up the sensor plate with a thin metal shim and then feathering it open with my hand but eventually dies

jpitman2

Bridge the pump relay to force it to circulate gas.....A few years ago i replaced my tank and some hoses, and based on an experience of doing LOTS (LOTS! - a couple of flattened batteries) of cranking before the lines were filled with gas, this time I bridged the pump relay, and let it run for 10-15mins - fired up FIRST try. Its a good leak test as well.
jp

Bikeartist1

Great idea for cleaning never thought about that.

karl ruiter

With the screen removed from the WUR your cold control pressure should be too low, making the car run too rich when cold. But that is only what should happen. Really the FD and the WUR work as a pair and if there is a FD issue then the WUR and control pressure will not have the effect you would expect. I was helping somebody with a '78 the other day that had a control pressure of 5bar (almost 3x what it should have been). I would have though this was because the WUR was blocked, but it was not blocked. Also I would have though the car would run completely lean, but the plugs were black. Pretty sure there is a FD issue there which is somehow making all the control pressure stuff I would expect be wrong.

Luis_M

The information above is partly incorrect. The pin inside the WUR actually goes up and increases control pressure at idle. It's counterintuitive, but if you disassemble the thing and leave only the inner spring on its seat on the base of the WUR, you will see that the spring goes up when you apply vaccuum on the side, not down. This leans out the mix at idle by increasing control pressure. The WSM shows about a 0.6 bar increase with 460-600mbar vacuum (see spec charts in section 25).

Jadz928

Ya know, Luis, I will get this right one of these times! Vacuum at idle raises the pin... will go back and edit post. Thanks (again)!